It is well known that there are several types of ventilation systems. The most widespread is natural ventilation, when the inflow and outflow of air is carried out through ventilation shafts, open vents and windows, as well as through cracks and leaks in structures.
Of course, natural ventilation is needed, but its operation is associated with a lot of inconvenience, and it is almost impossible to achieve cost savings with its device. Yes, and you can call ventilation the movement of air through ajar windows and doors with a big stretch - most likely, it will be ordinary ventilation. To achieve the required intensity of circulation of air masses, the windows must be open around the clock, which is unattainable in the cold season.
That is why a device for forced or mechanical ventilation is considered a more correct and rational approach. Sometimes it is simply impossible to do without forced ventilation, most often they resort to its device in industrial premises with degraded working conditions. Let us leave industrialists and production workers aside and turn our attention to residential buildings and apartments.
Often, in pursuit of savings, the owners of cottages, country houses or apartments invest a lot of money in warming and sealing their homes and only then realize that it is difficult to be indoors due to a lack of oxygen.
The solution to the problem is obvious - you need to arrange ventilation. The subconscious mind suggests that the best option would be an energy-saving ventilation device. The lack of properly designed ventilation can cause housing to turn into a real gas chamber. You can prevent this by choosing the most rational solution - a forced-exhaust ventilation device with heat and moisture recovery.
What is heat recovery
Recovery means its preservation. The outgoing air flow changes the temperature (heats, cools) of the supplied air by the supply and exhaust unit.
Scheme of operation of ventilation with heat recovery
The design assumes the separation of air flows to prevent their mixing. However, when using a rotary heat exchanger, the possibility of ingress of the discharged air stream into the incoming one is not excluded.
By itself, the "Air Recuperator" is a device that ensures the utilization of heat from exhaust gases. Through the separating wall between the heat carriers, heat exchange is carried out, while the direction of movement of air masses remains unchanged.
The most important characteristic of a heat exchanger is determined by the recovery efficiency or efficiency. Its calculation is determined from the ratio of the maximum possible heat recovery and the actual heat received behind the heat exchanger.
The efficiency of recuperators can vary over a wide range - from 36 to 95%. This indicator is determined by the type of recuperator used, the speed of the air flow through the heat exchanger and the temperature difference between the exhaust and incoming air.
Types of recuperators and their advantages and disadvantages
There are 5 main types of air recuperators:
- lamellar;
- Rotary;
- With intermediate coolant;
- Chamber;
- Heat pipes.
lamellar
The plate heat exchanger is characterized by the presence of plastic or metal plates. The discharged and incoming flows pass on opposite sides of the heat-conducting plates without contacting each other.
On average, the efficiency of such devices is 55-75%. A positive characteristic can be considered the absence of moving parts. The disadvantages include the formation of condensate, which often leads to freezing of the recuperative device.
There are plate heat exchangers with moisture-permeable plates that ensure the absence of condensate. The efficiency and principle of operation remain unchanged, the possibility of freezing of the heat exchanger is eliminated, but at the same time, the possibility of using the device to reduce the level of humidity in the room is also excluded.
In a rotary heat exchanger, heat transfer is carried out using a rotor that rotates between the supply and exhaust ducts. This device is characterized by a high level of efficiency (70-85%) and reduced power consumption.
The disadvantages include a slight mixing of flows and, as a result, the spread of odors, a large number of complex mechanics, which complicates the maintenance process. Rotary heat exchangers are effectively used for dehumidification of premises, therefore they are ideal for installation in swimming pools.
Recuperators with intermediate heat carrier
In recuperators with an intermediate heat carrier, water or a water-glycol solution is responsible for heat transfer.
The exhaust air provides heating of the coolant, which, in turn, transfers heat to the incoming air flow. The air flows do not mix, the device is characterized by a relatively low efficiency (40-55%), usually used in industrial premises with a large area.
Chamber recuperators
A distinctive feature of chamber recuperators is the presence of a damper that divides the chamber into two parts. High efficiency (70-80%) is achieved due to the possibility of changing the direction of the air flow by moving the damper.
Disadvantages include little mixing, odor transfer, and moving parts.
Heat pipes are a whole system of tubes filled with freon, which evaporates when the temperature rises. In another part of the tubes, freon is cooled with the formation of condensate.
The advantages include the exclusion of mixing flows and the absence of moving parts. The efficiency reaches 65-70%.
It should be noted that earlier recuperative units, due to their significant dimensions, were used exclusively in production, now small-sized recuperators are presented on the construction market, which can be successfully used even in small houses and apartments.
The main advantage of recuperators is the absence of the need for air ducts. However, this factor can also be considered as a disadvantage, since sufficient separation between exhaust and supply air is required for efficient operation, otherwise fresh air is immediately drawn out of the room. The minimum allowable distance between opposite air flows should be at least 1.5-1.7 m.
Why is moisture recovery needed?
Moisture recovery is necessary to achieve a comfortable ratio of humidity and room temperature. A person feels best at a humidity level of 50-65%.
During the heating period, the already dry winter air loses even more moisture due to contact with the hot coolant, often the humidity level drops to 25-30%. With this indicator, a person not only feels discomfort, but also causes significant harm to his health.
In addition to the fact that overdried air has a negative impact on the well-being and health of a person, it also causes irreparable damage to furniture and joinery made of natural wood, as well as paintings and musical instruments. Someone may say that dry air helps to get rid of dampness and mold, but this is far from the case. Such shortcomings can be dealt with by insulating the walls and arranging high-quality supply and exhaust ventilation while maintaining a comfortable level of humidity.
Ventilation with heat and moisture recovery: scheme, types, advantages and disadvantages
What is Heat Recovery Ventilation? How does this system work, what types are there and their pros and cons.
Heat recovery ventilation
During the period of the energy crisis and the rise in the price of energy resources, the use of energy-saving technologies in all areas of management becomes especially relevant. The role of heat recuperators in this matter cannot be underestimated. Engineering installations not only significantly save gas for space heating, but also, practically free of charge, return heat back for useful use, intended for release into the atmosphere.
Air exchange operation with air heating
Supply and exhaust ventilation with heat recovery solves three main tasks:
- providing the premises with fresh air;
- return of thermal energy leaving with air through the ventilation system;
- preventing cold streams from entering the house.
Schematically, the process can be considered with an example. The organization of air exchange is necessary even on a frosty winter day with a temperature outside the window of -22 ° C. To do this, the included supply and exhaust system, with the fan running, pumps air from the street. It seeps through the filter elements and, already cleaned, enters the heat exchanger.
As the air passes through it, it has time to warm up to + 14- + 15 ° С. Such a temperature can be considered sufficient, but does not meet sanitary standards for living. To achieve the parameters of room temperature, it is necessary to bring the air to the required values using the reheating function up to +20°C in the heat exchanger itself using a heater (water, electric) of low power - 1 or 2 kW. With such temperature indicators, air enters the rooms.
The heater operates in automatic mode: when the outside air temperature drops, it turns on and works until it warms up to the required values. At the same time, the waste stream is already heated to a “comfortable” 18 or 20 degrees. It is removed using the built-in ventilation unit, having previously passed through the heat exchange cassette. In it, he gives off heat to the oncoming cold air from the street, and only then goes into the atmosphere from the heat exchanger with a temperature of no more than 14-15 ° C.
Attention! The installation of metal-plastic structures disrupts the natural supply of fresh air flows to an apartment or house. The forced system solves the problem, supplying unheated air from the street, but also nullifying the energy saving efficiency from plastic windows. Supply and exhaust ventilation with a heat exchanger is a complex solution to the problem of heating with simultaneously functioning air exchange, an active method of saving energy.
Advantages of the supply and exhaust system with heating function
- Delivers fresh air, improves indoor air quality.
- Prevents loss of moisture on the surface, the formation of condensate, mold and mildew.
- Eliminates the conditions for the appearance of viruses, bacteria in the room.
- Saves the cost of electricity and heat energy by recovering losses from outgoing flows of about 90% of heat.
- Promotes regular air exchange.
- The versatility of the execution of heat exchange systems expands the scope of their application at objects of various types.
- Economical use and maintenance. Maintenance, including cleaning, replacing filters, checking all components and components of the system, is carried out annually only 1 time.
Attention! The operation of recuperators in old residential buildings will be inefficient, where natural air exchange is provided by wooden window structures, cracks in wooden floors and leaks in doors. The greatest effect of heat recovery is observed in modern buildings with high-quality insulation of rooms and good tightness.
Types of heat exchangers
The most common four categories of units are distinguished:
- rotary type. Works from the mains. Economical, but technically complex. The working element is a rotating rotor with metal foil applied over the entire surface. The heat exchanger with outside air passing inside reacts to the difference in temperatures outside and inside the rooms. This adjusts the speed of its rotation. The intensity of heat supply changes, icing of the heat exchanger is prevented in winter, which allows not to overdry the air. The efficiency of the devices is quite high and can reach 87%. In this case, mixing of oncoming flows (up to 3% of the total amount) and the flow of odors and pollution are possible.
- plate models. They are considered the most "running" because of the democratic price and efficiency. It reaches 40-65% thanks to the aluminum heat exchanger. Due to the absence of rotating and frictional components and parts, they are considered simple in execution and reliable in operation. Air streams separated by aluminum foil do not diffuse, they pass on both sides of the heat-conducting elements. Variety: plate model with plastic heat exchanger. Its efficiency is higher, but otherwise it has the same characteristics.
Attention! Plate devices lose before rotary ones in that they freeze and dry the air. Be sure to constantly moisturize it. The optimal scope of application is the humid environment of pools.
- Recycling view. Its “chip” is in its complex design and the use of a liquid carrier (water, water-glycol solution or antifreeze) as an intermediate in heat transfer. A heat exchanger is installed on the exhaust arm, which takes the heat from the outgoing air flow and heats the liquid with it. Another heat exchanger, but already at the air intake from the street, gives off heat to the incoming air without mixing with it. The efficiency of such installations reaches 65%, they do not participate in moisture exchange. It needs electricity to work.
- The roof type of devices is effective (58-68%), but not suitable for home use. It is used as an integral link in the ventilation of shops, workshops and other similar premises.
Calculation of the efficiency of the heat exchanger
It is possible to roughly calculate how efficient the installed supply ventilation with heat recovery will be, both in winter and summer, when the unit is working for cooling. The formula for calculating the temperature of the supply air flow for the installation, depending on the numerical characteristic of the energy efficiency (COP), the temperature of the air outside and in the room looks like this:
Tpr \u003d (tin - tul) * Efficiency + tul,
where temperature values:
Tp - expected at the outlet of the recuperator;
tvn - indoors;
For calculations, the passport value of the efficiency of the device is taken.
As an example: at frosts of -25°C and room temperature +19°C, as well as an installation efficiency of 80% (0.8), the calculation shows that the desired air parameters after passing through the heat exchanger will be:
Tpp \u003d (19 - (-25)) * 0.8 - 25 \u003d 10.2 ° С
The calculated temperature indicator of the air after the heat exchanger was obtained. In fact, given the inevitable losses, this value will be within +8°C.
In the heat at +30°C in the yard and 22°C in the apartment, the air in the heat exchanger of the same efficiency, before entering the room, is cooled to the design temperature:
Tpr \u003d tul + (tin - tul) * Efficiency
Substituting the data, we get:
Tpr \u003d 30 + (22-30) * 0.8 \u003d 23.6 ° С
Attention! The efficiency of the installation declared by the manufacturer and the actual one will differ. The value correction is affected by air humidity, the type of heat exchanger cassette, the value of the temperature difference between outside and inside. If the heat exchanger is not properly installed and operated, the efficiency of work is also reduced.
Modern energy-saving ventilation systems with the inclusion of recuperators in them are another step towards the economical use of heat carriers. Moreover, temperature exchange installations are relevant in winter, but no less in demand in summer.
Supply and exhaust ventilation with heat recovery
How does supply and exhaust ventilation with heat recovery work. What are the benefits of supply and exhaust ventilation with a heat exchanger.
Supply and exhaust ventilation systems with heat recovery and recirculation
Air recirculation in ventilation systems is a mixture of a certain amount of exhaust (exhaust) air to the supply air. Thanks to this, a reduction in energy costs for heating fresh air in the winter period of the year is achieved.
Scheme of supply and exhaust ventilation with recovery and recirculation,
where L is the air flow, T is the temperature.
Heat recovery in ventilation- this is a method of transferring thermal energy from the exhaust air stream to the supply air stream. Recuperation is used when there is a temperature difference between the exhaust and supply air, to increase the temperature of the fresh air. This process does not involve mixing air flows, the process of heat transfer occurs through any material.
Temperature and air movement in the heat exchanger
Heat recovery devices are called heat recuperators. They are of two types:
Heat exchangers-recuperators– they transfer heat flow through the wall. They are most often found in installations of supply and exhaust ventilation systems.
Regenerative recuperators- in the first cycle, which are heated from the outgoing air, in the second they are cooled, giving off heat to the supply air.
The supply and exhaust ventilation system with heat recovery is the most common way to use heat recovery. The main element of this system is the supply and exhaust unit, which includes a heat exchanger. The device of the supply unit with a heat exchanger allows transferring up to 80-90% of heat to the heated air, which significantly reduces the power of the air heater, in which the supply air is heated, in case of a lack of heat flow from the heat exchanger.
Features of the use of recirculation and recovery
The main difference between recuperation and recirculation is the absence of air mixing from the room to the outside. Heat recovery is applicable for most cases, while recirculation has a number of limitations, which are specified in regulatory documents.
SNiP 41-01-2003 does not allow re-supply of air (recirculation) in the following situations:
- In rooms, the air flow in which is determined on the basis of emitted harmful substances;
- In rooms in which there are pathogenic bacteria and fungi in high concentrations;
- In rooms with the presence of harmful substances, sublimated upon contact with heated surfaces;
- In rooms of category B and A;
- In rooms where work is carried out with harmful or combustible gases, vapors;
- In rooms of category B1-B2, in which combustible dusts and aerosols can be released;
- From systems with the presence in them of local suction of harmful substances and explosive mixtures with air;
- From vestibules-sluices.
Recirculation in air handling units is actively used more often with high system performance, when air exchange can be from 1000-1500 m 3 / h to 10000-15000 m 3 / h. The removed air carries a large supply of thermal energy, mixing it into the outside air flow allows you to increase the temperature of the supply air, thereby reducing the required power of the heating element. But in such cases, before being re-introduced into the room, the air must pass through the filtration system.
Recirculation ventilation improves energy efficiency, solves the problem of energy saving in the case when 70-80% of the exhaust air enters the ventilation system again.
Air handling units with recuperation can be installed at almost any air flow rate (from 200 m 3 /h to several thousand m 3 /h), both at low and at large. Recuperation also allows heat to be transferred from the extract air to the supply air, thereby reducing the energy demand on the heating element.
Relatively small installations are used in ventilation systems of apartments and cottages. In practice, air handling units are mounted under the ceiling (for example, between the ceiling and the suspended ceiling). This solution requires some specific requirements from the installation, namely: small overall dimensions, low noise level, easy maintenance.
The air handling unit with recuperation requires maintenance, which obliges to make a hatch in the ceiling for servicing the heat exchanger, filters, blowers (fans).
The main elements of air handling units
A supply and exhaust unit with recovery or recirculation, which has both the first and second processes in its arsenal, is always a complex organism that requires highly organized management. The air handling unit hides behind its protective box such main components as:
- Two fans of various types, which determine the performance of the installation by flow.
- Heat exchanger recuperator– heats the supply air by transferring heat from the exhaust air.
- Electric heater- heats the supply air to the required parameters, in case of a lack of heat flow from the exhaust air.
- Air filter- thanks to it, the control and purification of the outside air is carried out, as well as the processing of the exhaust air in front of the heat exchanger, to protect the heat exchanger.
- Air valves with electric actuators - can be installed in front of the outlet air ducts for additional air flow control and channel blocking when the equipment is turned off.
- bypass- thanks to which the air flow can be directed past the heat exchanger during the warm season, thereby not heating the supply air, but supplying it directly to the room.
- Recirculation chamber- providing the admixture of the exhaust air into the supply air, thereby ensuring the recirculation of the air flow.
In addition to the main components of the air handling unit, it also includes a large number of small components, such as sensors, an automation system for control and protection, etc.
Ventilation with recovery, recirculation
Design, calculation, requirements for ventilation with recovery, recirculation. Free consultation.
Features of the ventilation system with heat recovery, its principle of operation
The heat recuperator often becomes part of the ventilation system. However, not many people know what kind of device it is and what features it has. Also, an important question is whether the purchase of a recuperator will pay off, how it will change the operation of the ventilation system, whether it is possible to create such an element with your own hands. These and many other questions will be answered in the information below.
How the system works
An unusual name was given to a conventional heat exchanger. The task of the device is to take part of the heat from the already exhausted exhaust air from the room. The extracted heat is transferred to the flow, which comes from the clean air supply system. The above information determines that the purpose of using such a system is to save on heating the house. In doing so, the following points should be noted:
- In the summer, the system allows you to reduce the cost of air conditioning work.
- The device in question can work in both directions, that is, it takes heat in the supply and exhaust systems.
How a heat recovery system works
The above information determines that the heat exchanger is installed in many ventilation systems. It is not active, many versions do not consume energy, do not emit noise, and have an average efficiency indicator. Heat exchangers have been installed for many years, but lately many have been wondering if there is any reason to complicate the ventilation system with this device, which has quite a few problems due to working in an environment with different temperatures.
Problems installing the system
There are practically no potential problems associated with the use of such equipment. Some are decided by the manufacturer, others become a headache for the buyer. The main problems include:
- Condensation formation. The laws of physics determine that when air with a high temperature passes through a cold closed environment, condensation occurs. If the ambient temperature is below zero, then the fins will begin to freeze. All information given in this paragraph determines a significant reduction in the efficiency of the device.
- Energy efficiency. All ventilation systems that work together with the heat exchanger are energy dependent. The ongoing economic calculation determines that only those recuperator models that will save more energy than they spend will be useful.
- Payback period. As previously noted, the device is designed to save energy. An important determining factor is how many years it takes for the purchase and installation of recuperators to pay off. If the indicator under consideration exceeds the mark of 10 years, then there is no point in installing, since during this time other elements of the system will require replacement. If the calculations show that the payback period is 20 years, then the installation of the device should not be considered.
The occurrence of condensation on the vent. system
The above problems should be taken into account when choosing a heat exchanger, which there are several dozen types.
Device options
Sidebar: Important: There are several variants of the heat exchanger. Considering the principle of operation of the device, it should be borne in mind that it depends on the type of the device itself. The plate type of the device is a device in which the supply and exhaust channels pass through a common housing. The two channels are separated by partitions. The partition consists of numerous plates, which are often made of copper or aluminum. It is important to note that the copper composition has a higher thermal conductivity than aluminum. However, aluminum is cheaper.
The features of this device include the following:
- Heat is transferred from one channel to another by means of heat-conducting plates.
- The principle of heat transfer determines that the problem of the appearance of condensate arises immediately after the inclusion of a heat exchanger in the system.
- In order to eliminate the possibility of condensation, a thermal-type icing sensor is installed. When a signal from the sensor appears, the relay opens a special valve - the bypass.
- When the valve is opened, cold air enters into two channels.
This class of device can be attributed to the low price category. This is due to the fact that when creating the structure, a primitive method of heat transfer is used. The efficiency of such a method is lower. An important point can be called the fact that the cost of the device depends on its size and the size of the supply system itself. An example is the size of the channel 400 by 200 millimeters and 600 by 300 millimeters. The difference in price will be more than 10,000 rubles.
Ventilation scheme with recuperation
The design consists of the following elements:
- Two inlet air ducts: one for fresh air, the second for exhaust air.
- From the coarse filter of the supplied air from the street.
- Directly to the heat exchanger itself, which is located in the central part.
- Damper, which is necessary to supply air in case of icing.
- Condensate drain valve.
- A fan that is responsible for forcing air into the system.
- Two channels on the reverse side of the structure.
The dimensions of the heat exchanger depend on the power of the ventilation system and the dimensions of the air ducts.
The next type of design can be called a device with heat pipes. Its device is almost identical to the previous one. The only difference is that the design does not have a huge number of plates that penetrate the partition between the channels. For this, a heat pipe is used - a special device that transfers heat. The advantage of the system is that freon evaporates at the warmer end of the sealed copper tube. Condensation accumulates at the colder end. The features of the considered design include:
The operation of the system has the following features:
- The system has a working fluid that absorbs heat energy.
- Steam spreads from a warmer point to a colder point.
- The laws of physics dictate that the vapor condenses back into a liquid and releases the stored temperature.
- Through the wick, the water again flows to a warm point, where it is again formed into steam.
The design is sealed and works with high efficiency. The advantage is that the design is smaller and easier to operate.
The rotary type can be called a modern version. On the border between the supply and exhaust ducts there is a device that has blades - they rotate slowly. The device is designed in such a way that the plates are heated on one side and transferred from the second side by rotation. This is because the blades are angled to redirect heat. The features of the rotary system include the following:
- Fairly high efficiency. As a rule, plate and tubular systems have an efficiency of no more than 50%. This is due to the fact that they do not have active elements. When redirecting the air flow, it is possible to increase the efficiency of the system up to 70-75%.
- The rotation of the blades also determines the solution to the problem of condensation on the surface. The problem is also solved with low humidity in the cold season.
However, there are also several disadvantages:
- As a rule, the more complex the system, the less reliable it is. The rotor system has a rotating element that can fail.
- If there is high humidity in the room, then it is not recommended to use the structure.
It is also important to understand that the recuperator chambers do not have a hermetic separation. This moment determines the transfer of odor from one chamber to another. In general, the rotor system resembles a kind of fan of rather large overall dimensions with bulky blades. To improve the efficiency of the system, the device must be connected to a power source.
The intermediate type heat carrier is a classic design, which consists of water heating with convectors and pumps. The system is used extremely rarely, due to low efficiency and design complexity. However, it is practically irreplaceable in the case when the supply and exhaust channels are at a great distance from each other. Heat is transferred through water, which has been used for many years to create such systems. To ensure the circulation of water, regardless of the location of the devices in the system, a pump is installed. It is important to understand that the design features in this case determine the low reliability of the system and the need for periodic inspections.
Features of the ventilation system with heat recovery, its principle of operation
Ventilation with heat recovery provides a comfortable and healthy microclimate in the house and heat preservation. Definition of effectiveness and implementation options.
Supply and exhaust ventilation with heat recovery: principle of operation, overview of advantages and disadvantages
The intake of fresh air during the cold period of time leads to the need to heat it to ensure the correct microclimate of the premises. To minimize energy costs, supply and exhaust ventilation with heat recovery can be used.
Understanding the principles of its operation will allow you to reduce heat losses as efficiently as possible while maintaining a sufficient volume of replaced air.
Energy saving in ventilation systems
In the autumn-spring period, when ventilating rooms, a serious problem is the large temperature difference between the incoming and inside air. The cold stream rushes down and creates an unfavorable microclimate in residential buildings, offices and factories or an unacceptable vertical temperature gradient in a warehouse.
A common solution to the problem is the integration of a heater into the supply ventilation, with the help of which the flow is heated. Such a system requires electricity, while a significant amount of warm air coming out leads to significant heat losses.
If the air inlet and outlet channels are located nearby, then it is possible to partially transfer the heat of the outgoing stream to the incoming one. This will reduce the consumption of electricity by the heater or completely abandon it. A device for ensuring heat exchange between different-temperature gas flows is called a recuperator.
In the warm season, when the outdoor air temperature is much higher than the room temperature, a heat exchanger can be used to cool the incoming flow.
Block device with recuperator
The internal structure of supply and exhaust ventilation systems with an integrated heat exchanger is quite simple, so their independent element-by-element purchase and installation is possible. In the event that assembly or self-assembly is difficult, you can purchase ready-made solutions in the form of standard monoblock or individual prefabricated structures on order.
Basic elements and their parameters
The body with heat and sound insulation is usually made of sheet steel. In the case of wall mounting, it must withstand the pressure that occurs when foaming the slots around the unit, and also prevent vibration from the operation of the fans.
In the case of a distributed intake and air flow in various rooms, an air duct system is attached to the building. It is equipped with valves and dampers for flow distribution.
In the absence of air ducts, a grill or diffuser is installed on the inlet from the side of the room to distribute the air flow. An external type air intake grille is mounted on the inlet from the side of the street to prevent birds, large insects and litter from entering the ventilation system.
Air movement is provided by two fans of axial or centrifugal types of action. In the presence of a heat exchanger, natural air circulation in sufficient volume is impossible due to the aerodynamic resistance created by this unit.
The presence of a recuperator implies the installation of fine filters at the inlet of both streams. This is necessary to reduce the intensity of dust and grease clogging of the thin channels of the heat exchanger. Otherwise, for the full functioning of the system, it will be necessary to increase the frequency of preventive maintenance.
One or several recuperators occupy the main volume of the air handling unit. They are mounted in the center of the structure.
In case of severe frosts typical for the territory and insufficient efficiency of the heat exchanger, an additional air heater can be installed to heat the outside air. Also, if necessary, install a humidifier, ionizer and other devices to create a favorable microclimate in the room.
Modern models provide for the presence of an electronic control unit. Complex modifications have the functions of programming operating modes depending on the physical parameters of the air environment. External panels have an attractive appearance, thanks to which they can fit well into any interior of the room.
Solving the problem of condensation
The cooling of the air coming from the room creates the preconditions for the unloading of moisture and the formation of condensate. In the case of a high flow rate, most of it does not have time to accumulate in the heat exchanger and goes outside. With slow air movement, a significant part of the water remains inside the device. Therefore, it is necessary to ensure the collection of moisture and its removal outside the body of the supply and exhaust system.
The output of moisture is carried out in a closed container. It is placed only indoors in order to avoid freezing of the outflow channels at sub-zero temperatures. There is no algorithm for reliable calculation of the volume of water received when using systems with a recuperator, so it is determined experimentally.
The reuse of condensate for air humidification is undesirable, since the water absorbs many pollutants such as human sweat, odors, etc.
Significantly reduce the amount of condensate and avoid the problems associated with its appearance by organizing a separate exhaust system from the bathroom and kitchen. It is in these rooms that the air has the highest humidity. If there are several exhaust systems, the air exchange between the technical and residential area must be limited by installing non-return valves.
In the case of cooling of the outgoing air flow to negative temperatures inside the heat exchanger, the condensate passes into frost, which causes a reduction in the effective cross section of the flow and, as a result, a decrease in the volume or a complete cessation of ventilation.
For periodic or one-time defrosting of the heat exchanger, a bypass is installed - a bypass channel for the movement of supply air. When the flow bypasses the device, the heat transfer stops, the heat exchanger heats up and the ice passes into a liquid state. Water flows into the condensate collection tank or it evaporates to the outside.
When the flow passes through the bypass, there is no heating of the supply air through the heat exchanger. Therefore, when this mode is activated, it is necessary to automatically turn on the heater.
Features of various types of recuperators
There are several structurally different options for implementing heat transfer between cold and heated air flows. Each of them has its own distinctive features, which determine the main purpose for each type of recuperator.
Plate cross-flow heat exchanger
The design of a plate heat exchanger is based on thin-walled panels connected in turn in such a way as to alternate the passage of different temperature flows between them at an angle of 90 degrees. One of the modifications of this model is a device with finned channels for air passage. It has a higher heat transfer coefficient.
Heat exchange panels can be made of various materials:
- copper, brass and aluminum-based alloys have good thermal conductivity and are not susceptible to rust;
- plastics made of polymeric hydrophobic material with a high coefficient of thermal conductivity are lightweight;
- hygroscopic cellulose allows condensate to penetrate through the plate and back into the room.
The disadvantage is the possibility of condensation at low temperatures. Due to the small distance between the plates, moisture or frost significantly increases the aerodynamic drag. In case of freezing, it is necessary to shut off the incoming air flow to warm up the plates.
The advantages of plate heat exchangers are as follows:
- low cost;
- long service life;
- long period between preventive maintenance and ease of its implementation;
- small dimensions and weight.
This type of heat exchanger is most common for residential and office premises. It is also used in some technological processes, for example, to optimize fuel combustion during the operation of furnaces.
Drum or rotary type
The principle of operation of a rotary heat exchanger is based on the rotation of the heat exchanger, inside which there are layers of corrugated metal with a high heat capacity. As a result of interaction with the outgoing flow, the drum sector is heated, which subsequently gives off heat to the incoming air.
The advantages of rotary recuperators are as follows:
- sufficiently high efficiency compared to competing types;
- the return of a large amount of moisture, which remains in the form of condensate on the drum and evaporates upon contact with the incoming dry air.
This type of heat exchanger is less commonly used for residential buildings with apartment or cottage ventilation. It is often used in large boiler houses to return heat to furnaces or for large industrial or commercial and entertainment premises.
However, this type of device has significant disadvantages:
- a relatively complex design with moving parts, including an electric motor, a drum and a belt drive, which requires constant maintenance;
- increased noise level.
Sometimes for devices of this type you can find the term "regenerative heat exchanger", which is more correct than "recuperator". The fact is that a small part of the outgoing air gets back due to the loose fit of the drum to the body of the structure.
This imposes additional restrictions on the possibility of using devices of this type. For example, polluted air from heating furnaces cannot be used as a heat carrier.
Tube and shell system
The tubular type heat exchanger consists of a system of thin-walled tubes of small diameter located in an insulated casing, through which outside air is supplied. A warm air mass is removed from the room through the casing, which heats the incoming flow.
The main advantages of tubular heat exchangers are as follows:
- high efficiency, due to the countercurrent principle of movement of the coolant and incoming air;
- simplicity of design and the absence of moving parts ensures low noise levels and a rarely occurring need for maintenance;
- long service life;
- the smallest section among all types of recuperation devices.
Tubes for this type of device use either light-alloy metal or, less commonly, polymer. These materials are not hygroscopic, therefore, with a significant difference in flow temperatures, intense condensate may form in the casing, which requires a constructive solution for its removal. Another disadvantage is that the metal filling has a significant weight, despite the small dimensions.
The simplicity of the design of the tubular heat exchanger makes this type of device popular for self-manufacturing. As an external casing, plastic pipes for air ducts, insulated with polyurethane foam shells, are usually used.
Device with intermediate heat carrier
Sometimes the supply and exhaust air ducts are located at some distance from each other. This situation may arise due to the technological features of the building or sanitary requirements for reliable separation of air flows.
In this case, an intermediate heat carrier is used, which circulates between the air ducts through an insulated pipeline. As a medium for transferring thermal energy, water or a water-glycol solution is used, the circulation of which is provided by the pump.
In the event that it is possible to use another type of heat exchanger, it is better not to use a system with an intermediate heat carrier, since it has the following significant disadvantages:
- low efficiency compared to other types of devices, therefore, such devices are not used for small rooms with low air flow;
- significant volume and weight of the entire system;
- the need for an additional electric pump for fluid circulation;
- increased noise from the pump.
There is a modification of this system, when instead of forced circulation of the heat exchange fluid, a medium with a low boiling point, such as freon, is used. In this case, movement along the contour is possible in a natural way, but only if the supply air duct is located above the exhaust duct.
Such a system does not require additional energy costs, but works for heating only with a significant temperature difference. In addition, it is necessary to fine-tune the point of change in the state of aggregation of the heat exchange fluid, which can be implemented by creating the desired pressure or a certain chemical composition.
Main technical parameters
Knowing the required performance of the ventilation system and the heat exchange efficiency of the heat exchanger, it is easy to calculate the savings on air heating for a room under specific climatic conditions. By comparing the potential benefits with the costs of purchasing and maintaining the system, you can reasonably make a choice in favor of a heat exchanger or a standard heater.
Efficiency
The efficiency of a heat exchanger is understood as the efficiency of heat transfer, which is calculated using the following formula:
- T p - the temperature of the incoming air inside the room;
- T n - outdoor air temperature;
- T in - the air temperature in the room.
The maximum efficiency value at a nominal air flow rate and a certain temperature regime is indicated in the technical documentation of the device. His real figure will be slightly less. In the case of self-manufacturing of a plate or tubular heat exchanger, in order to achieve maximum heat transfer efficiency, it is necessary to adhere to the following rules:
- The best heat transfer is provided by countercurrent devices, then by cross-flow devices, and the smallest - with unidirectional movement of both flows.
- The intensity of heat transfer depends on the material and thickness of the walls separating the flows, as well as on the duration of the presence of air inside the device.
where P (m 3 / hour) - air consumption.
The cost of recuperators with high efficiency is quite high, they have a complex design and large dimensions. It is sometimes possible to circumvent these problems by installing several simpler devices in such a way that the incoming air passes through them in series.
Ventilation system performance
The volume of air passed through is determined by the static pressure, which depends on the power of the fan and the main components that create aerodynamic drag. As a rule, its exact calculation is impossible due to the complexity of the mathematical model, therefore, experimental studies are carried out for typical monoblock structures, and components are selected for individual devices.
The fan power must be selected taking into account the throughput of any type of heat exchangers installed, which is indicated in the technical documentation as the recommended flow rate or the amount of air passed by the device per unit of time. As a rule, the permissible air velocity inside the device does not exceed 2 m/s.
Otherwise, at high speeds, a sharp increase in aerodynamic resistance occurs in the narrow elements of the recuperator. This leads to unnecessary energy costs, inefficient heating of the outside air and a shortened life of the fans.
Changing the direction of the air flow creates additional aerodynamic drag. Therefore, when modeling the geometry of an indoor duct, it is desirable to minimize the number of pipe turns by 90 degrees. Diffusers to disperse air also increase resistance, so it is advisable not to use elements with a complex pattern.
Dirty filters and gratings create significant flow problems and must be cleaned or replaced periodically. One of the effective ways to assess clogging is to install sensors that monitor the pressure drop in the areas before and after the filter.
The principle of operation of a rotary and plate heat exchanger:
Measurement of the efficiency of a plate-type heat exchanger:
Domestic and industrial ventilation systems with an integrated heat exchanger have proven their energy efficiency in keeping indoor heat. Now there are many offers for the sale and installation of such devices, both in the form of ready-made and tested models, and on an individual order. You can calculate the necessary parameters and perform the installation yourself.
Supply and exhaust ventilation with heat recovery: device and operation
Supply and exhaust ventilation device with heat recovery. Types of recuperators, their advantages and disadvantages. Calculation of efficiency and nuances of ensuring the required performance.
Comfortable suburban housing cannot be imagined without a good ventilation system, since it is they who are the key to a healthy microclimate. However, many are cautious and even wary about the implementation of such an installation, fearing huge electricity bills. If certain doubts have “settled” in your head, we recommend that you look at a recuperator for a private house.
We are talking about a small unit, combined with supply and exhaust ventilation and excluding excessive consumption of electrical energy in the winter, when the air needs additional heating. There are several ways to reduce unwanted expenses. The most effective and affordable is to make an air recuperator with your own hands.
What is this device and how does it work? This will be discussed in today's article.
Features and principle of operation
So what is heat recovery? - Recuperation is a heat exchange process in which cold air from the street is heated by the outflow from the apartment. Thanks to this organization scheme, a heat recovery installation saves heat in the house. A comfortable microclimate is formed in the apartment in a short period of time and with minimal electricity consumption.
The video below shows the air recovery system.
What is a recuperator. General concept for the layman.
The economic feasibility of a recuperative heat exchanger depends on other factors:
- energy prices;
- the cost of installing the unit;
- the costs associated with servicing the device;
- the lifetime of such a system.
note! An air recuperator for an apartment is an important, but not the only element necessary for effective ventilation in a living space. Ventilation with heat recovery is a complex system that functions exclusively under the condition of a professional "bundle".
Recuperator for home
With a decrease in ambient temperature, the efficiency of the unit decreases. Be that as it may, a heat exchanger for a house during this period is vital, since a significant temperature difference "loads" the heating system. If it is 0°C outside the window, then an air stream warmed up to +16°C is supplied to the living space. A household recuperator for an apartment copes with this task without any problems.
Formula for calculating efficiency
Modern air recuperators differ not only in efficiency, nuances of use, but also in design. Consider the most popular solutions and their features.
Main types of structures
Experts focus on the fact that there are several types of heat:
- lamellar;
- with separate heat carriers;
- rotary;
- tubular.
lamellar type – includes a structure based on aluminum sheets. Such a heat exchanger installation is considered the most balanced in terms of the cost of materials and the value of thermal conductivity (the efficiency varies from 40 to 70%). The unit is distinguished by its simplicity of execution, affordability, and the absence of moving elements. Installation does not require specialized training. Installation without any difficulties is carried out at home, with your own hands.
plate type
Rotary are solutions that are quite popular among consumers. Their design provides for a rotation shaft powered by the mains, as well as 2 channels for air exchange with counterflows. How does such a mechanism work? - One of the sections of the rotor is heated by air, after which it turns and the heat is redirected to the cold masses concentrated in the adjacent channel.
rotary type
Despite the high efficiency, the installations have a number of significant drawbacks:
- impressive weight and size indicators;
- exactingness to regular maintenance, repair;
- it is problematic to reproduce the recuperator with your own hands, to restore its performance;
- mixing of air masses;
- dependence on electrical energy.
You can watch the video below about the types of recuperators (starting from 8-30 minutes)
Recuperator: why is it, their types and my choice
note! A ventilation unit with tubular devices, as well as separate heat carriers, is practically not reproduced at home, even if all the necessary drawings and diagrams are at hand.
DIY air exchange device
The simplest in terms of implementation and subsequent equipment is considered to be a plate-type heat recovery system. This model boasts both obvious "pluses" and annoying "minuses". If we talk about the merits of the solution, then even a home-made air recuperator for the home can provide:
- decent efficiency;
- lack of "binding" to the power grid;
- structural reliability and simplicity;
- availability of functional elements and materials;
- duration of operation.
But before you start creating a recuperator with your own hands, you should also clarify the disadvantages of this model. The main disadvantage is the formation of glaciers during severe frosts. The level of moisture in the street is less than in the air that is present in the room. If you do not act on it in any way, it turns into condensate. During frosts, high humidity levels contribute to the formation of frost.
The photo shows how air is exchanged.
There are several ways to protect the heat exchanger device from freezing. These are small solutions that differ in efficiency and implementation method:
- thermal effect on the structure due to which the ice does not linger inside the system (the efficiency drops by an average of 20%);
- mechanical removal of air masses from the plates, due to which the forced heating of the ice is carried out;
- addition of a ventilation system with a recuperator with cellulose cassettes that absorb excess moisture. They are redirected to housing, while not only condensate is eliminated, but also a humidifier effect is achieved.
We offer you to watch a video - Do-it-yourself air recuperator for home.
Recuperator - do it yourself
Recuperator - DIY 2
Experts agree that cellulose cassettes are the best solution today. They function regardless of the weather outside the window, while the installations do not consume electricity, they do not require a sewer outlet, a condensate collector.
Materials and components
What solutions and products should be prepared if it is necessary to assemble a plate-type home unit? Experts strongly recommend paying priority attention to the following materials:
- 1. Aluminum sheets (textolite and cellular polycarbonate are quite suitable). Please note that the thinner this material is, the more efficient the heat transfer will be. Supply ventilation in this case works better.
- 2. Wooden slats (about 10 mm wide and up to 2 mm thick). They are placed between adjacent plates.
- 3. Mineral wool (up to 40 mm thick).
- 4. Metal or plywood to prepare the body of the apparatus.
- 5. Glue.
- 6. Sealant.
- 7. Hardware.
- 8. Corner.
- 9. 4 flanges (under the pipe section).
- 10. Fan.
note! The diagonal of the body of the recuperative heat exchanger corresponds to its width. As for the height, it is adjusted for the number of plates and their thickness in conjunction with the rails.
Device drawings
Metal sheets are used to cut squares, the dimensions of each side can vary from 200 to 300 mm. In this case, it is necessary to select the optimal value, taking into account which ventilation system is installed in your home. There should be at least 70 sheets. To make them smoother, we recommend working with 2-3 pieces at the same time.
Diagram of a plastic device
In order for energy recovery in the system to be fully carried out, it is necessary to prepare wooden slats in accordance with the selected dimensions of the side of the square (from 200 to 300 mm). Then they must be carefully processed with drying oil. Each wooden element is glued to the 2nd side of the metal square. One of the squares must be left unpasted.
In order for the recovery, and with it the ventilation of the air, to be more efficient, each upper edge of the rails is carefully coated with adhesive. Individual elements are assembled into a square "sandwich". Very important! The 2nd, 3rd and all subsequent square products should be rotated 90 ° in relation to the previous one. In this way, the alternation of channels is implemented, their perpendicular position.
The upper square is fixed on the glue, on which there are no slats. Using the corners, the structure is carefully pulled together and fastened. In order for heat recovery in ventilation systems to be carried out without air loss, the gaps are filled with sealant. Flange mounts are formed.
Ventilation solutions (manufactured unit) are placed in the housing. Previously, on the walls of the device, it is necessary to prepare several corner guides. The heat exchanger is positioned in such a way that its corners rest against the side walls, while the whole structure visually resembles a rhombus.
In the photo, a homemade version of the device
Residual products in the form of condensate remain in its lower part. The main task is to obtain 2 exhaust channels isolated from each other. Inside the structure of the lamellar element, air masses are mixed, and only there. A small hole is made at the bottom to drain condensate through a hose. In the design, 4 holes are made for the flanges.
Formula for calculating power
Example! For heating the air in the room up to 21°C, which requires60 m3 of airat one o'clock:Q \u003d 0.335x60x21 \u003d 422 W.
To determine the efficiency of the unit, it is enough to determine the temperatures at 3 key points of its entry into the system:
Calculation of recuperator payback
Now you know , what is a recuperator and how necessary it is for modern ventilation systems. These devices are increasingly being installed in country cottages, social infrastructure facilities. Recuperators for a private house are a fairly popular product in our time. At a certain level of desire, the recuperator can be assembled with your own hands from improvised means, as mentioned above in our article.
Many of the buildings currently under construction, both industrial and residential, have very complex infrastructures and are designed with the greatest emphasis on energy efficiency. Therefore, it is impossible to do without installations of such systems as general air ventilation systems, smoke protection systems and air conditioning systems. To ensure the efficient and long service life of ventilation systems, it is necessary to design and install a high-quality general air ventilation system, a smoke protection system and an air conditioning system. Installation of such equipment of any type must be carried out with the obligatory observance of certain rules. And according to the technical characteristics, it must correspond to the volume and type of premises in which it will be operated (residential building, public, industrial).
Of great importance is the correct operation of systems: compliance with the terms and rules for preventive inspections, scheduled preventive repairs, as well as the correct and high-quality adjustment of ventilation equipment.
For each ventilation system in Moscow, accepted for operation, a passport and an operating log are drawn up. The passport is drawn up in two copies, one of which is stored at the enterprise, and the other in the technical supervision service. The passport contains all the technical characteristics of the system, information about the repairs carried out, copies of the as-built drawings of the ventilation equipment are attached to it. In addition, the passport reflects a list of operating conditions for all components and parts of ventilation systems.
According to the established schedule, scheduled inspections of ventilation systems are carried out. During scheduled inspections:
- Defects are identified, which are eliminated during the current repair;
- The technical condition is determined;
- Partial cleaning and lubrication of individual components and parts are carried out.
All data of the planned inspection of ventilation systems are mandatory indicated in the operation log.
Also, during the working shift, the on-duty operational team provides for scheduled overhaul maintenance of ventilation systems. This service includes:
- Start-up, regulation and shutdown of ventilation equipment;
- Supervision of the operation of ventilation systems;
- Monitoring the compliance of the parameters of the air environment and the temperature of the supply air;
- Elimination of minor defects.
Commissioning of general air ventilation systems, smoke protection systems and air conditioning systems
The stage of commissioning is a very important stage, because the high-quality work of ventilation and air conditioning depends on commissioning.
During commissioning, the work of the installation team is visible, and the parameters specified in the project are checked and compared with the parameters of the equipment with those specified in the project documentation. During the inspection, a complete check of the technical condition of the installed equipment, the distribution and uninterrupted operation of adjustment devices, the installation of control and diagnostic devices, and the identification of errors in the operation of the equipment are carried out. If deviations are detected that are within the normal range, then the readjustment does not occur, and the object is prepared for delivery to the customer, with the execution of all documents.
All masters of our company have a specialized education, certificates in health and safety, rich work experience and have all the necessary documents and certificates.
At the stage of commissioning, we measure the air flow velocity in the air ducts, the noise level, approbation of the quality of equipment installation, adjustment of engineering systems in accordance with the project parameters, certification.
Start-up tests and adjustment of ventilation and air conditioning systems must be carried out by a construction and installation or a specialized commissioning organization.
Certification of systems
A technical document drawn up on the basis of a check of the working condition of ventilation systems and equipment, carried out using aerodynamic tests, is called certification of the ventilation system.
SP 73.13330.2012 "Internal sanitary systems of buildings", updated version of SNIP 3.05.01-85 "Internal sanitary systems" regulate the form and content of the ventilation system passport.
Obtaining a ventilation system passport, in accordance with the requirements of the above document, is mandatory.
At the end of the installation work, the customer receives a passport for the ventilation system.
A passport must be obtained for each ventilation system.
The passport is indispensable for the registration of purchased equipment, for the correct operation of such equipment, in order to achieve the necessary sanitary and hygienic air parameters.
In the period established by law, this document is provided by the control and supervisory authority. The receipt of this document is an indisputable proof in resolving disputes with the relevant authorities.
Obtaining a ventilation system passport can be carried out as a separate type of work, consisting of a set of aerodynamic tests. The conduct of such events is regulated by the following regulations:
- SP 73.13330.2012;
- STO NOSTROY 2.24.2-2011;
- R NOSTROY 2.15.3-2011;
- GOST 12.3.018-79. “Ventilation systems. Methods of aerodynamic tests”;
- GOST R 53300-2009;
- SP 4425-87. "Sanitary and hygienic control of industrial premises";
- SanPiN 2.1.3.2630-10.
A recuperator (lat. receiving back, returning) is a special supply and exhaust device that removes exhaust air from the room and supplies fresh air from the street. One of the key structural elements is the heat exchanger. Its functional purpose is to take heat, and in some systems, moisture, from the exhaust air and transfer it to the incoming fresh air. All recuperators are characterized by low power consumption.
What material are heat exchangers in recuperators made of?
The material of the heat exchanger is one of the important factors that must be considered when choosing a ventilation system. Here, the individual characteristics of the place of operation of the system are taken into account so that the node lasts as long as possible. At the moment, in the manufacture of the heat exchanger, it is used: aluminum, copper, ceramics, plastic, stainless steel and paper.
What are the advantages of a domestic recuperator?
There are many advantages of ventilation with recuperation, among the most significant it is worth noting the ability to provide both supply and exhaust with one device, as well as saving up to 50% on heating / cooling costs, normalizing humidity and reducing the level of harmful substances in the room air. The device is able to provide a favorable microclimate, regardless of the season and the weather outside.
How much heat is saved by heat recovery?
Any device provides a level of recovery at the level of 70-90%. The indicator depends on external conditions and mode of operation. When organizing all ventilation in the room on recuperators, it is possible to achieve savings in heating / cooling costs of up to 60%
For example, for the climatic zone of Siberia, the use of a heat exchanger allows you to save on electricity (when using a heater) up to 50-55%.
Is there a risk of drafts during the operation of the heat exchanger?
The performance of recuperators does not allow a draft in the literal sense of the word, however, when choosing an installation site, it is better to minimize possible discomfort in the future on frosty days and not place devices directly above workplaces and sleeping places.
Is it possible to install a heat exchanger in a city apartment?
Yes, but with a few caveats. Recuperators are not recommended to be installed in rooms with a well-functioning common house hood. But if the window openings are closed with sealed double-glazed windows, and the common house exhaust system does not work well. It is the supply and exhaust system with recuperation that is an effective tool to combat stuffiness, high humidity, mold and unpleasant odors.
How noisy are household recuperators?
Each specific installation has its own indicator - it depends on the power and mode of operation. But in general, the noise level at the first speeds is so insignificant that most people do not notice it. And at the last speeds, any device is noisy.
Is it true that recuperators effectively solve the problem of indoor humidity?
If excessive humidity in the rooms appears due to low-efficiency ventilation or its complete absence, then the installation of any heat exchanger will radically change the situation for the better. The equipment will ensure normal air exchange in the room, which means the removal of moisture in a natural way.
What is the level of energy consumption of domestic recuperators?
Any ventilation system with recuperation refers to economical climate equipment. It requires from 2 to 45 W / h of electrical energy to work. Which is in monetary terms from about 100 to 1500 rubles a year.
What should be the thickness of the wall for the installation of a wall-mounted heat exchanger?
If the thickness of the wall structure is 250 mm or more, then there will be no problems with the installation of a domestic ventilation system with recuperation - everything is done according to the standard algorithm. If this parameter is below the given indicator, then specialists apply individual solutions. For example, Wakio has a Wakio Lumi model for thin walls, and a special wall extension hood for Marley MEnV 180. There are also systems that are not demanding on wall thickness, such as Mitsubishi Lossnay Vl-100.
How many ventilation units will be optimal for one apartment?
Normal air exchange is considered when the air in the room is completely renewed in one hour. With an average room area of 18 meters and a ceiling height of 2.5 m, it turns out that about 45 cubic meters per hour must be supplied and removed. Almost any household recuperator will cope with this task. However, there is another way to calculate the required volume of air - by the number of people in the room. In this case, according to the law of Moscow, it is required to supply and remove 60 cubic meters per hour per person. In this case, household recuperators are installed in pairs and this method is considered the most optimal.
Are there any types of buildings where it is impossible to use a household heat exchanger?
There are no direct prohibitions on the installation of domestic recuperators, however, in state-protected architectural monuments, holes cannot be made in the wall; in all other buildings, the organization of a hole with a diameter of up to 200 mm is not prohibited by law. High floors with strong winds and rooms with a very strong general house exhaust can also serve as a limitation, here the installation of recuperators is not recommended.
Is it allowed to install ventilation systems in already operated buildings where people live?
Where does the condensate go?
A high level of heat recovery creates conditions for the appearance of condensate - this is a natural process. In installations with heat recovery, due to part of this moisture, the incoming air flow is humidified, that is, comfortable climatic conditions are created in the room. And the excess through a special top cover is brought out in such a way that it does not settle on the facade. Whatever the weather outside, the system's shift cycle prevents dew points. So the equipment does not freeze. It is also worth noting that the amount of condensate produced is not at all large.
What is the peculiarity of the functioning of the ventilation unit in the summer?
There are no differences in the operation of equipment in winter and summer. The main principle is always observed - the heat remains in the environment where it was originally located. Thus, the temperature regime at any time of the year does not change when heat recovery is turned on. And if it is necessary to cool the air, the function is disabled - the “ventilation” mode is set by means of the controllers of the installation.
Are there features of bathroom ventilation based on domestic recuperators?
It is impossible to overestimate the relevance of the installation in the bathroom - excess moisture is removed from the room, and the temperature regime remains comfortable. In bathrooms, it is recommended to install recuperators with a humidity sensor, so ventilation will work automatically and only when necessary.
Can microbes breed in household recuperators?
First of all, we note that the problem of microbes is relevant for places where moisture accumulates for a long time. And since the heat exchanger of the device is completely dried under any conditions, no microorganisms can multiply in it. To be completely sure, we recommend carrying out preventive cleaning of the heat exchanger 2 times a year - simply wash it under running water or in a dishwasher. The element can also be steam cleaned.
What is the frequency of cleaning ventilation devices?
There is no clear answer here. A number of factors are taken into account - the intensity of operation of the premises, its purpose, and the climatic zone. We recommend visually checking the degree of contamination of filters and heat exchangers and cleaning as necessary.
Will the hole in the wall under the heat exchanger become a source of cold penetration into the room?
As long as the system is in recovery mode, there is zero risk of thermal bridges. When the system is off, the heat in the heat exchanger clogs the hole and does not escape. True, the correct location of the heat exchanger is important - it must be pushed far enough outward, and a shut-off air valve must be located on the side of the room.
Whom to contact regarding the choice of the location of ventilation units?
Choosing the optimal location for ventilation units with recuperation is a free service for our company's customers. We are ready to provide it at a convenient time for you with a site visit.
Is it possible to install a household heat exchanger on my own?
Theoretically, in houses made of SIP panels, wood and frame houses, the heat exchanger can be installed independently, however, in this case, the device loses the warranty for installation, and often the warranty for the device itself. It is not possible to install a heat exchanger in stone houses on your own, since this requires expensive professional equipment that is not used in everyday life, as well as a specialist in diamond drilling.
