Manufacture of an indirect heating boiler by hand. Do-it-yourself indirect heating boiler - types, advantages, disadvantages and manufacturing technology. Boiler from a gas cylinder

The problem of lack of connection to hot water supply is relevant for many of us. The way out of this situation will be the installation of appropriate boilers that allow you to heat water, providing the necessary comfort of living in an apartment or private house. Today, hundreds of such heating boilers can be found on sale, which differ in the principle of their operation and a number of other characteristics.

Design of an indirect heating boiler

The principle of operation of such a water heater is based on the use of a heat carrier from heating system, enabling at minimal cost get the amount you need hot water. Such a boiler can use a separate or common circuit of the heating system, which makes it easy to integrate it into engineering Communication at home.

Boiler design indirect heating consists of a sealed storage tank, with a coil located inside, through which the heated coolant from the heating system circulates. Cold water is fed into the tank through the inlet pipe located at the bottom, and the warm liquid is taken through the corresponding pipe at the top of the storage tank. Despite its relative simplicity of design, such a home-made indirect heating water heater is efficient, which allows it to heat water in the required volumes.

Advantages and disadvantages of indirect heating boilers

Let's talk in more detail about the advantages and disadvantages of such heating boilers, which are often installed in cottages and private houses where there is no connection to the gas main and centralized heating.

The advantages of this technology are:

The simplicity of the water heater and ease of installation.
The heating boiler is connected to a central or autonomous heating system.
Making an indirect heating water heater with your own hands is not difficult.
Excellent efficiency and the ability to obtain hot water at a constant temperature.

Disadvantages of boilers indirect heating is still available:

The need to clean the coil from deposits.
Additional space is required to install such equipment.
In the event that the heating system does not function, heating the water in the boiler becomes much more complicated.

Today, combined indirect heating water heaters are very popular, which use both the coolant from the heating system and additional electric heat. heating element, which provides the highest possible energy independence similar water heating boiler.

How to make an indirect heating boiler with your own hands

The simplicity of this design and its efficiency has invariably affected the popularity of boilers among domestic homeowners. There is a possibility self-manufacturing such indirect heating boilers, which can significantly save on the purchase of expensive heating water heating equipment. We'll tell you more how to make such a boiler with your own hands.

The volume of the storage capacity of the water heater should be calculated based on the daily consumption of hot water in the house. In the event that several people live in an apartment or house, a 100-liter tank will suffice. And for a family of 4-5 people, you should choose a container with a volume of 200-300 liters.

The tank used must be made of an alloy of aluminium, stainless steel or other metal that is resistant to corrosion. You can use large gas cylinder, the walls of which are additionally cleaned and primed. If the walls of the cylinder are not primed, then hot water may have an unpleasant smell of gas.

In the selected tank five holes must be drilled. Two for the bottom inlet pipe and emergency drain, two on the side for installing the coil and one hole for water extraction from above. In the event that it is planned to use such a boiler outside heating season it is also necessary to make holes for installing an electric heating element. For the heating element, one or two holes are drilled from the bottom. Installed in the holes made Ball Valves or locking elements, after which the tightness of the storage tank is checked.

Choosing a coil

Used coil is one of the most important elements in the design of an indirect heating boiler. This element can be made of brass or copper tube. The length of the coil and its diameter are calculated based on the volume of the tank and the temperature of the coolant in the heating system. The heating element itself can be made of a tube with a diameter of 8-20 millimeters, which is coiled. The completed turns should not come into contact with each other, which allows for maximum heating efficiency.

The length of the coil is calculated according to the appropriate formula, when the required thermal power is divided by the Pi number, which is multiplied by the pipe diameter and the temperature difference between the coolant and water in the tank. So, for example, to heat a 200 liter tank, you will need a coil with a thermal power of 30 kW. If coil tube is used 10 millimeters, and the temperature difference is 65 degrees, then you will need to make a coil with a diameter of 40 centimeters and a tube length of 15 meters. Accordingly, such a coil will have approximately 12-13 turns.

The required heat output of the coil can be calculated from the ratio of 1.5 kW of heat output per 10 liters of storage capacity. Accordingly, by carrying out such a simple calculation, you can get required power coil, and subsequently calculate its dimensions.

It is easiest to bend the coil according to the existing template. You can choose a suitable size steel pipe and bend a coil along it, which is made of soft brass or copper.

Tank insulation

To improve heating efficiency it is recommended to cover the outside of the tank with a layer of insulation. For such insulation, we recommend using mineral wool, polyurethane foam or any other heat insulator that is attached to a wire outside the tank or fixed with ties.

You can also insulate the tank by inserting such a self-made boiler into the tank larger diameter. The cavities between the containers are filled with foam or other insulating material. In fact, we will get an impromptu thermos that holds heat well and allows you to quickly heat water.

Having made all the constituent components and prepared the necessary parts, you can start assembling an indirect heating boiler:

This completes the manufacture and connection of the indirect heating water heater. It is necessary to check the tightness and operability of the completed heating equipment, and, if necessary, perform its additional adjustment.

Despite the apparent simplicity of this design, it provides efficient heating, while the costs for receipt warm water will be minimal. You can make such an indirect heating boiler with your own hands, and in the future such equipment will not require any complex maintenance and repair.

Remember only that once a year you should clean the coil from the plaque that has appeared and lime deposits. Cleaning is carried out as mechanically, and with the help of special chemicals that dissolve calcium and lime deposits.

Conclusion

An indirect heating boiler will completely solve the problem with warm water without hot water connection. It is not difficult to make an indirect heating boiler with your own hands, which will save a lot without losing the functionality and efficiency of such equipment. Such a boiler is made from improvised materials, and each of us can perform calculations on the coil.

To secure a private home hot water for economic needs, various Appliances. It includes instantaneous water heaters and various boilers - electric, gas and indirect heating. The latter are of the greatest interest, since they do not require any energy carriers for their operation. On the other hand, similar units factory-made are very expensive. That's why to do indirect boiler with your own hands - good decision, and how to implement it, we will tell in this article.

The device and principle of operation of an indirect heating boiler

What makes these units so attractive is the ability to deliver a large amount of hot water to several consumers at once. The heating takes place without additional connections to electrical network or a gas main, the source of heat is the same boiler that we use to heat the house. The only condition is that the heat generator must have a power reserve in order to have time to work with the heating system and the water heater.

I must say that the device of an indirect heating boiler is quite simple, so if you have some skills, you can do it yourself. In fact, this is a round sealed tank of decent capacity (at least 100 liters), inside of which is placed a copper tube coil. Outside, the tank is covered with a heat-insulating layer that prevents the water in the tank from cooling down quickly. The water heater device is shown in detail in the diagram:

The figure shows a conventional indirect boiler in the minimum configuration, more than perfect models additionally equipped with:

a second coil for connecting an alternative heat source;
electric heater to maintain the water temperature in the event of a boiler shutdown;
thermometer and manometer.

The very principle of operation of an indirect heating boiler is to transfer heat indirectly from the boiler to the mass of water in the tank. The mediator is a coolant heated to a temperature of 70-80 ° C and circulating through the copper tube of the coil. This allows you to bring the temperature of the water intended for domestic hot water to 60 ° C. In order to exclude electrochemical corrosion of the metal tank, magnesium anode, which forms a more active galvanic pair copper - magnesium than copper - steel.

Also, an indirect type storage water heater is equipped with a branch pipe for connecting a safety safety valve and a temperature sensor connected to the thermostat. In the event that it is necessary to provide an instant supply of hot water to the mixers, the boiler is equipped with a branch pipe for connecting the return recirculation line.

To make an indirect heating boiler at home, you will need 2 main elements - this is the tank itself and a copper tube heat exchanger. The ideal shape for the tank is cylindrical, so it is better to use some kind of cylinder as such, metal barrel or thin wall pipe large diameter. The copper tube should not be too thin, such a heat exchanger will not be effective. Suitable Diameter- 15-20 mm.

Advice. For the manufacture of a heat exchanger, corrugated stainless pipe used for heating and water supply systems. It is easier to bend than copper.

Having picked up a suitable tank and decided on its dimensions, you can start winding the coil. For this, it is recommended to use a template in the form of a pipe or a log, whose diameter is half smaller size containers. After fixing one end of the tube, wind onto the template as tightly as possible, coil by coil. At the same time, it is necessary to monitor the height of the product so that it subsequently fits inside the boiler, made by oneself.

The finished heat exchanger is installed in the center of the tank so that the tube does not touch its walls anywhere. Now we need to arrange sealed passage tubes through the tank, which is done by soldering and threaded connections as shown in the photo:

Now it remains to insulate the tank with roll insulation and bandages made of wire or thin steel strip. First you need to finish all the welding work - attach the bottom and cover, cut in all the pipes and weld the supports. A decorative casing made of sheet metal or other convenient material should be put on top of the insulation.

Advice. In order to extend the life of the homemade steel tank it is recommended to purchase and install a magnesium anode inside the water heater.

Scheme of connecting the boiler to the boiler

Assembling a storage water heater is only half the battle, you still need to complete correct installation unit and its connection to a heat source. Since the water tank has a fairly large weight, it is better to put it on the foundation and align it vertically. If the floors in your boiler room are flooded concrete screed 100 mm thick, then you can do without a foundation. After installation, you can start tying the boiler.

Advice. Perhaps someone advised you to connect the boiler to the hot water path double-circuit boiler or you found a similar scheme on the Internet. Remember that these units cannot be connected in this way, the water heater must be connected to the same line as the heating system.

The fact is that a double-circuit boiler heats water for the needs of hot water only up to 60 ° C. And this means that it will heat a large volume of water in the boiler to no more than 50 ° C, while spending a lot of time. There is another point: when the heat generator works for the DHW circuit, it is completely disconnected from the heating system, as a result of which the latter will cool down significantly, and with it the whole house. All the nuances are described in detail in the following video:

In order to properly combine the water heater and the boiler into one properly functioning system, it is necessary to tie them according to one of the diagrams below. In the first, the distribution of coolant flows is organized by installing a three-way valve with a servo drive. When the temperature of the water inside the boiler begins to decrease, the actuator sends the coolant flow to the coil of the unit at the signal of the sensor.

In another connection scheme with two circulation pumps, the indirect heating boiler is loaded by turning on the pump in its circuit. Heating circuit at the same time, it can function constantly or turn off, which depends on the automation. If the heat output of the boiler is sufficient, then both branches can operate simultaneously. You just need to choose the right pumps so that they do not interfere with each other.

Another way of tying the boiler is used in complex systems with several circulation pumps and a hydraulic separator.

Here, the water heater with its pump is simply connected to the common collectors located behind the hydraulic gun. More details about correct connection indirect heating boiler is shown in the video below.

Installation of a safety valve for a water heater

This small device plays an important role in the boiler connection scheme. When the water in the tank begins to heat up, it expands in volume and as a result, the pressure increases.

When it reaches a critical value, it works and dumps some of the water to reduce pressure. Therefore, the valve nozzle must be connected with a flexible tube to the sewer outlet.

in tanks large capacity it is customary to additionally put a membrane expansion tank(expansomat). It is able to compensate for a larger volume of expanding fluid. At the same time, it is important when buying a tank to choose one that is intended for water supply systems, and not heating. You can recognize it by the value of the maximum working pressure of 7-8 Bar (for tanks for heating 3 Bar).

In addition to these elements, other necessary parts must be present in the boiler piping from the water supply side: taps, valves, filters and other fittings. How to properly tie an indirect water heater with the water supply of a private house is shown in the diagram with a reverse circulation circuit:

Conclusion

In fact, the design of a storage water heater is not difficult, so if you wish, you can make it yourself. At the same time, it is possible to equip the boiler with all possible functions and integrate sensors into it for joint work with boiler automation. But you will have to tinker with the strapping, the effective operation of the entire heating of the house depends on the correctness of its implementation.

Owners of private housing have to use various heating equipment, which requires significant maintenance and efficient operation. An indirect heating boiler is an excellent addition to a gas and electric heating system. The device reduces energy consumption for heating water and ensures its constant flow.

What is an indirect heating boiler

An indirect heating boiler is a water heating tank that functions in conjunction with devices central heating. Unlike traditional water heaters, an indirect type boiler does not require an electrical connection.

Indirect heating boilers may have different design, but all of them heat water due to the energy of the boiler coolant

Water heating occurs due to heat exchange between hot water flowing through the heat exchanger and cold water, which is filled with a boiler tank. Externally, the boiler is a cylindrical container with a capacity of tens to several thousand liters.

Indirect water heaters are used both in private houses, the owners of which do not have the ability to connect to autonomous central heating, and in large industries where large amounts of hot water are required.

Advantages and disadvantages of indirect heating equipment

Among the advantages of an indirect type boiler are:

economy (no electricity costs);
high performance of the equipment, limited only by the power of the heating boiler;
no direct contact between running water and coolant;
the possibility of consuming thermal energy from several sources at once to increase the power and efficiency of the boiler.

Significant disadvantages of the equipment include:

Video: experience using an indirect type boiler

Types of indirect heating boilers

Modern indirect boilers have varied design and form. In addition to the rounded thin-walled tank, there are boilers that have more complex device allowing the equipment to be more economical and efficient. Classification of equipment is carried out according to several criteria.

Types of heat exchanger

Indirect water heaters can have a heat exchanger of various designs:

Heat exchanger material

For the manufacture of a heat exchanger in the form of a coil and an internal tank, materials such as:

brass - low thermal conductivity, 100–110 W/(m∙°C);
aluminum - average thermal conductivity, 200–240 W/(m∙°C);
copper - high thermal conductivity, 360–390 W / (m ∙ ° C).

The higher the thermal conductivity of the heat exchanger material, the more expensive the boiler.

Installation method

Depending on the installation method, the devices are divided into two types:

Layout method

By way of location structural elements water heaters are divided into two types:

Choosing a boiler for self-production

The general arrangement of an indirect heating boiler is quite simple - with the ability to work with power tools and welding, a water heater can be made independently.

For use in a private home where a family from three people, a vertical boiler with a copper heat exchanger is sufficient. If the family is large, then it is better to choose a floor structure. This will make it possible to make the equipment of the required capacity, as well as to carry out proper thermal insulation of the tank.

It is not advisable to make a boiler with a tank-in-tank heat exchanger on your own. Firstly, you will need to find or make the tank itself, which will require a lot of time and effort. Secondly, in the manufacture of water heaters large volume the dimensions of the structure are increased several times.

In addition, factory models manufactured using this technology have a special coating (enamel, ceramic, silver plating) on the heat exchanger. It will not work to repeat the application of such a coating in "garage conditions".

Design features of an indirect boiler

The indirect type boiler is a tank made of stainless steel. The inner walls of the container are covered special material, which not only protects the surface of the water heater from corrosion processes, but also reduces the concentration of harmful bacteria and microorganisms.

Scheme of the device of an indirect type boiler with a single-circuit coil

The rest of the boiler the simplest design consists of the following components:

heat exchanger - spiral tube or smaller tank. Depending on the volume of the tank, it can be located in its upper and lower parts;
inlet pipe - fitting in the lower part of the device for supplying a pipe with cold running water;
outlet pipe - a fitting for connecting a hot water outlet pipe;
magnesium anode - additional protection of the tank walls from corrosion processes;
internal thermometer - a device for measuring the temperature of water heating;
thermostat - a device that prevents overheating of equipment;
control unit - rotary knob with divisions for setting the heating temperature;
thermal insulation - a layer of insulating material that helps maintain the desired temperature of heated water;
outlet - valve for draining stagnant water;
revision - a large diameter hole designed for maintenance, repair and modernization of the boiler.

The design of new tank models may differ slightly and have a number of improvements from manufacturers, but in general, any indirect type boiler consists of the listed elements.

The principle of operation of the boiler

An indirect type boiler is part of the heating system and is connected directly to gas, electric or solid fuel boiler, which heats the coolant due to the energy released during fuel combustion.

The heat carrier circulates through the DHW system and passes through the heat exchanger located in the indirect heating boiler. Due to the release of thermal energy from the hot coolant, cold water is heated, which fills the device reservoir. From it, heated water is transported through the outlet through the pipe to the bathroom, to the kitchen and to other rooms with sanitary equipment.

An indirect type boiler can work with any type of heating boiler

When the heating boiler is turned off or it switches to an economical mode of operation, the coolant cools down quickly. Due to the design, which provides for the insulation of the walls of the tank with urethane foam, the water in the tank cools very slowly. This allows you to use the entire volume of warm water for several more hours.

Calculation of the main parameters of the boiler

Before proceeding with the search for material and direct manufacturing, it will be necessary to calculate the minimum volume of the tank and the working length of the heat exchanger.

Volume and shape of the tank

The volume of the water tank directly depends on the number of residents permanently residing at the place where the equipment is installed. It is believed that a person consumes up to 80 liters of water per day. For the calculated value, it is recommended to take 45-50 liters per person. If the norm is exceeded, the water in the tank will stagnate, which will certainly affect its quality.

The shape of the tank is selected taking into account the pressure force in the plumbing system. If the pressure is low, then homemade boilers with a square tank are allowed. At high pressure in the system, only equipment with a rounded bottom and top can be used.

Boilers with a storage tank of square and rectangular shape can only be used in water supply systems with low operating pressure

The fact is that high blood pressure contributes to the occurrence of bending forces on the walls of the tank, so a square or rectangular tank can be deformed. A container with a round bottom is more resistant to deformation due to better streamlining.

Heat exchanger power and length

In vertical models of indirect heating, a copper coil is usually used as a heat exchanger, located between the inlet and outlet.

Boiler coil made of copper pipe

For self-production, it is best to use a copper pipe with a diameter of 10 mm. Such a product can be easily bent by hand without the use of any tool. Using metal-plastic pipe it should be borne in mind that the heating temperature of the coolant should not be more than 90 ° C, otherwise the pipe will deform and the joints will leak - this will lead to mixing of water in the tank.

The length of the pipe required for the manufacture of the coil is calculated by the formula L \u003d P / (3.14 ∙d ∙∆T), where:

L - pipe length (m);
d - pipe section (m);
∆Т - temperature difference between heated and cold water (o C);
P is the power of the heat exchanger for every 10 liters of water (kW).

According to experts, for every 10 liters of water there should be at least 1.5 kW of thermal energy. With this in mind, you can calculate the length of the pipe for the manufacture of the coil.

For example, we will calculate the material for the coil, which will be installed in a boiler with a capacity of 200 liters. The temperature of the cold water supplied to the tank will be 15 ° C, and after heating it is necessary to obtain water with a temperature of 80 ° C: L \u003d 1.5 ∙ 20 / (3.14 ∙ 0.01 ∙ 65) ≈ 15 m.

Table: length of copper heat exchanger for boilers with a capacity of 50–200 liters

The number of turns of the coil depends on the method of bending and the distance between the elements. Usually the coil is positioned so that the distance between the coils and the walls of the tank is at least 10-12 cm. The distance between the coils should not be less than 5 cm. Calculated values for storage tanks of various volumes can be seen in the table above.

If an indirect type boiler must be equipped with a tubular electric heater, then the power is calculated based on the fact that a heating element with a power of at least 1.5 kW is required to quickly heat 50 liters of water. In addition, any combined boiler must be equipped with a thermostat.

Necessary materials and tools

The storage tank of the device is made of heat-resistant plastic, stainless steel, aluminum or steel with a ceramic coating. As blanks for the tank, you can take plastic barrels for food products, aluminum tanks or an unnecessary gas cylinder.

For the manufacture of a heat exchanger, as mentioned above, it is better to use a round or square copper pipe. When assembling a heat exchanger from square pipes, bends under 90 o will be required.

As a tool, you need to prepare:

Fitting, drain tap and other connecting elements are selected based on the dimensions of the connected pipe. Additionally, an FUM tape, a safety valve, a magnesium anode and a nozzle for its installation are purchased.

Preparing a tank for assembling a water heater

For the manufacture of an indirect type boiler, you can use a new or old gas cylinder. This tank is made of thick stainless steel 3-4 mm thick and is perfect for working with hot water.

Before assembling the heating structure, you will need to carefully prepare the cylinder. To do this, the product is cut in half with a grinder. The inner surface of the container is cleaned using an angle grinder with a suitable nozzle.

Before assembling the boiler, the cylinder must be opened and the inner surface cleaned

After that, the inside of the cylinder is washed, dried and covered with nitro-primer paint. These works should be carried out without fail, otherwise, after the boiler is put into operation, the heated water will smell like gas.

When using a tank from other metal containers preparation is carried out in a similar way.

Manufacture of an indirect heating boiler

The process of assembling a water heater may vary depending on the type of construction, but in most cases, equipment for gas and electric boilers is manufactured in the following sequence:

In a pre-prepared cylinder, two holes are drilled using an electric drill with a crown nozzle. One hole will be located at the bottom and used to supply cold water, the other - at the top to drain hot.
The resulting holes are cleaned, fittings and ball valves are mounted in them. Then another hole is drilled in the lower part, into which a tap is installed to drain the stagnant water.
Holes are made in the lower and upper parts of the cylinder into which taps are inserted to connect water pipes
To make a coil, you will need copper pipe 10 mm in diameter. A spiral bend is best done with a pipe bender. If there is no such tool, then you can take any round billet- large diameter pipe, log, barrel, etc.
Making a coil for a water heater from a round copper pipe with a diameter of 10 mm
The coil is being manufactured according to the calculations made earlier. The ends of the heat exchanger are bent in one direction at a distance of 20–30 cm. Two holes are drilled in the lower part of the cylinder to mount the coil. Threaded fittings are installed and welded into them.
A threaded fitting is used to connect the coil to the boiler
Before installation, the coil is lowered into a bucket or large container of water and blown through. If the design is tight, then the coil is lowered into the cylinder, set relative to the inlet and outlet and brewed.
If the cylinder was cut in the middle, then an anode is mounted in the upper part. To do this, a hole is drilled, where a threaded nozzle is screwed in, and a magnesium anode is already mounted in it. If the container is assembled from three separate parts - bottom, lid and central part, then the anode can be installed at the last stage.
FROM outer side boiler is mounted thermal insulation material. It is best to use sprayed polyurethane. Before application, all nozzles are protected with dense polyethylene and cloth. If funds are limited, then you can use ordinary mounting foam, which, after hardening, turns into reflective insulation.
For thermal insulation, it is easiest to use mounting foam and foil insulation
Attachments are welded to the back of the boiler for hanging on brackets. For floor boilers, support legs from a steel angle or fittings are welded to the bottom of the equipment.

At the final stage, fittings, taps are screwed on and mounted top cover. If possible, the cover can not be welded, but clamping fasteners can be made of steel wire with a cross section of 3 mm.

When manufacturing a boiler for use with solid fuel boilers instead of a copper coil is used steel pipe U-shaped, which is mounted at the bottom of the device. On the side of the furnace or boiler, the pipe is connected to the outlet. From the boiler, the pipe is removed and connected directly to the chimney.

Video: indirect heating boiler from a gas cylinder

Boiler piping for indirect heating

Three working schemes are used to connect an indirect type boiler:

Trim with a three-way valve.
Connection to two circulation pumps.
Tying with the use of hydraulic arrows.

Trim with three-way valve

The piping scheme using a three-way valve is most often used, especially when a large amount of hot water is consumed. For this, two heating circuits are mounted in the system. The first is the main circuit used for space heating. The second one is designed to heat water in the boiler.

The piping scheme for an indirect heating boiler with a three-way valve is most often used

For uniform distribution and regulation of the volumes of the coolant entering the boiler, three-way valve which is connected to the thermostat.

The principle of operation of the system is quite simple: if the temperature in the storage tank drops below the set value, the valve redirects part of the coolant to heat the water in the boiler. After heating the water, the coolant returns to the heating circuit.

Piping with two circulation pumps

An indirect type water heater is installed in a system with two circuits: a boiler and heating. A recirculation pump is used to regulate each individual circuit. In this case, the pump is mounted on the boiler circuit in front of the heating equipment pump.

In the piping scheme with circulation pumps, the coolant supply to the boiler is automatically regulated

Both pumps are connected to the boiler thermostat. When the water in the boiler cools down, the thermostat turns on the corresponding pump, which redirects part of the flow from the heating and vice versa.

Strapping using a hydraulic gun

Piping using a hydraulic separator is used in central heating systems consisting of two or more circuits. If in a system without a hydraulic arrow, the redistribution of flows in the circuits necessarily affects the operation of any equipment, then when it is installed, a smooth redistribution of cold and hot flows occurs.

The boiler piping scheme with the installation of a hydraulic separator ensures the smoothest distribution of cold and hot water flows

For example, a hydraulic separator must be installed in private houses, where, in addition to the indirect heating boiler, an underfloor heating system is connected to the central heating system. The scheme of this strapping is rather complicated in execution, especially when in large numbers equipment. Therefore, it is better to entrust the work on its installation to specialists.

Coolant recirculation system

This piping scheme is used if it is necessary to minimize the rate of water heating in the boiler, since with frequent downtime, the water in the tank cools quickly, and it takes 30 to 60 minutes to reheat it.

To do this, a "return" to the water heater is mounted in the pipeline going from the boiler to the water tap. A circulation pump connected to a thermostat is also installed in this area.

When the water in the pipeline stagnates and cools, the thermostat turns on the pump, which redirects the cooled water back to heating. When the water supply is resumed, the user does not have to wait for it to heat up, as it will already be warm.

Features of the operation of an indirect boiler

To function properly, the boiler must be placed on a flat, solid surface. During installation wall-mounted boiler appropriate fasteners calculated on the weight of the device filled with water.

A tank with a capacity of up to 100 liters is mounted on dowel-nails 100 mm long, and for equipment with a capacity of 150–200 liters, fasteners up to 150 mm long must be used. It is advisable to hang the boiler on walls made of concrete or brick.

A non-return valve must be installed on the cold water supply line before the boiler, which will prevent hot water from entering the cold circuit.

The indirect heating boiler is connected to the system through a check valve

The main problem in the operation of indirect type boilers is the formation of scale inside the storage tank and heat exchanger when water is heated above 80 ° C. Therefore, with a moderate consumption of hot water (washing dishes), it is advisable to reduce the temperature to a comfortable 40–50 ° C. This will significantly prolong service life of the equipment.

Boiler cleaning and repair

If the boiler is used frequently, the tank should be cleaned once a year. To do this, a concentrated solution of citric or acetic acid is pumped into the tank and heated to a temperature of 80–90 ° C. After 20–30 minutes, the liquid is drained. If the heating system uses a coolant in the form of ordinary water, then for the purpose of prevention, the heat exchanger is cleaned in a similar way.

If a leak occurs at the pipe junctions, it is necessary to disassemble the problem area and re-install it using a larger amount of sealant. Instead of sanitary flax more modern materials should be used, for example, FUM tape or plumbing thread.

Video: installation and piping of an indirect type boiler

An indirect type water heater is an equipment that must be installed in every private and country house where gas or electric heating. This will reduce the cost of hot water supply by 15-20%, which will be a very tangible savings in the face of ever-increasing tariffs.

Hello. My name is Vitaliy. Area of professional activity: technical means automation and design technology. (2 votes, average: 5 out of 5)

Sometimes a homemade water heater is great option save on the necessary expensive equipment. It can be used as a temporary option in the event of a breakdown. old technology or permanently, for example, in country houses where the need for hot water is seasonal. Of course, for permanent water supply in a private house or apartment, it is best to use factory systems. The manufacture and installation of a home-made device for heating water does not require special experience, anyone can make it. The main thing is the availability of the necessary material and tools for work. So, how to make a water heater with your own hands?

Of course, do-it-yourself self-made pressure storage water heaters will be more convenient to use. But their assembly requires additional investments and knowledge. Such systems should be equipped circulation pump to maintain a pressure of 1 atm or connect to a water supply system already installed in the house.

If the budget is limited and there is no way to purchase such additional equipment, or there is no water supply system in the house at all, you should pay attention to the non-pressure option. Such a water heater with your own hands can be made from an ordinary bucket or large-capacity pan. The main thing is to mount such a device higher so that water runs out of it. under the force of gravity. But you will have to constantly monitor the filling of the storage tank and the water temperature.

Since it is difficult to provide a mixing system in such a home-made device, it is initially worth heating the water no higher than 40 degrees.

What to make a storage tank

Before you make a water heater, you need to decide on the design features of the future boiler. Most often, this storage capacity with a heating element installed inside it, which is responsible for heating the water.

For storage tank it is better to choose containers made of corrosion-resistant metal. The most suitable options: stainless or enameled steel, high-quality plastic, aluminum. You can also use iron tanks, only they will have to be pre-treated with a special protective composition, which the minimizes rust formation. Otherwise, the water passing through such a heating device may not be suitable for domestic use.

For homemade storage water heaters use the most various capacities, as an example, a gas cylinder can be noted. This is a fairly convenient tank in size, shape and strength.

How to make a water heater from a gas cylinder

Ideally, if purchased for this new vessel. If this is not possible, use a used cylinder. To get rid of the smell of gas, it should be carefully treat with a nitro primer and rinse the inside. To do this, the balloon will first have to be cut, and then welded again.

Worth paying Special attention that before performing work that will be associated with a violation of the integrity of the cylinder, it must be filled with water in order to exclude the possibility of an explosion.

Tools and materials:

welding machine and drill for metal;
metal-cutting tool for threading (die);
screwdrivers and gas key;
empty gas cylinder;
heating element with thermostat;
insulating composition for heating elements (grease or tow);
metal eyeliners;
nut, safety and check valves;
fasteners for fixing the finished boiler.

Manufacturing instructions.

Do-it-yourself water heater is almost ready. Now the device can be filled with water and checked for leakage. If all is well, you can connect the heating element and use the device.

Do-it-yourself economical water heater

The constant increase in electricity tariffs is forcing many consumers to switch to saving mode. A good option is a do-it-yourself storage boiler powered by solar energy.

To make it you will need:

storage tank of large volume (100-200 liters);
pvc pipes and hoses for water supply;
fasteners.

Instructions on how to make an economical boiler for a summer cottage:

holes for pipes are made in the storage barrel;
hoses are connected to them;
the capacitive tank is installed in a sunny place protected from the wind;
water supply is organized (it can be a hose connected to the water supply);
a conclusion is made to a tap or an outdoor shower.

Under the influence sun rays the water in the barrel is heated, and it can be used for your needs. it practical option for organization summer shower on his garden plot. Often such barrels are installed directly on the roof of various buildings. In order to make the most of natural energy and achieve maximum efficiency from such a device, next to the tank in which the water is located, reflective elements(for example, the remains of a foil substrate for a laminate), or the tank itself is painted in a dark color.

If desired, anyone can make a water heater with their own hands. The main thing is to think over the design features of the equipment in advance, choose suitable materials and secure the water heating system.

What is indirect heating, and how to implement it yourself? The concept of operation is the same as that of thermal power plants (TPP). In the process of solving the main problem (the operation of generators for steam), “extra” thermal energy appears. It can be irresponsibly released into the atmosphere, or directed to the organization of heating the microdistrict.

The indirect heating unit works exactly the same way. We take a heat source (which exists regardless of your need to extract additional benefits from it), and “take away” part of the thermal energy from it.

Thus the inhabitants communal apartments without hot water supply, hot water was obtained (mainly for washing dishes, sometimes for taking a shower). For this, in collaboration with neighbors, an indirect heating boiler was made by hand. The solution is simple, but requires at least a gas torch for pipe welding. Either the unit was manufactured in the “left” way at the main place of work (as a rule, a factory or a repair shop).

The simplest heat exchanger

Homemade heater looks like this:

A sheath of a larger diameter is welded onto the central heating pipe. It turns out a sealed vessel, inside which a hot coolant flows. FROM opposite sides external pipe (in fact, this is a boiler), flanges are arranged for the supply (drain) of cold water. With a sufficiently hot coolant, the water in the boiler heats up quickly. After that, the top tap can be opened and hot water can be used until hot water is replaced by cold water.

Leaving aside the legitimacy of re-equipping the collective heating network (hardly any serious responsibility is envisaged for this), the system works efficiently. Hot water is conditionally free, minus one-time investments for materials, and a bottle of strong drink for the welder.

If you arrange such instantaneous water heater with your own hands in private households - there will be no conditional problems.

The only limitation is the volume of the outer container. In real time, the water will not heat up, the supply of thermal energy in the heating pipe is too small. Therefore, the system works cyclically: heating - use - heating. The higher the ratio of diameters (or the longer the pipe), the greater the supply of hot water. Accordingly, the longer it will warm up.

Another serious drawback: in the summer (when the heating is turned off), such heaters do not work.

advanced design

How to improve heat transfer? That's right, you need to increase the contact area. Of course, the material of the inner pipe is also important, the copper pipe transfers heat much more efficiently. But in this design, the emphasis is on savings, so we make an indirect heating boiler with our own hands from steel.

To improve the heat transfer coefficient, several schemes can be applied:

We have already considered the classic version.
"U" shaped with the same overall length almost doubles the performance.
Double "U" guarantees a twofold increase in efficiency

Important according to p.p. 2 and 3:

Thermodynamics is not a linear science. With an increase in the exchange area in such imperfect structures as a pipe-in-pipe boiler, the coefficient useful action changes differentially.

Creation of additional volume due to the formation of a kind of "fold" in the outer tube. Allows you to accumulate more water secondary heating.
The coil significantly increases the length of the device, with unchanged dimensions.
The so-called "turbo" scheme. Complex design primary pipe (with heat carrier) increases the time of passage of heat through the outer shell.

Storage systems with a large volume

We found out what is the main drawback of the pipe-in-pipe water heating element. Indirect heating takes too long. Since it is difficult to increase heat transfer, a larger container can be used to heat water. Then you can “conjure” over the heat exchanger. The best option in the illustration: a coil inside a wide body.

The design is a tank of the required capacity (50, 100, 200 liters), inside of which there is a coil (the longer, the more efficient the heating). The heat source does not matter: it is usually the space heating circuit. The water in the sanitary (internal) tank warms up quickly enough. The only problem is the uneven distribution of heat. A “cold” area remains at the bottom of the container. In spite of correct scheme selection of heated water (receiving pipe from above), the cold area does not allow the entire volume to warm up.

Moreover, the materials are not in short supply. The tank will fit from the old washing machine activator type. BUT copper tube sold at any plumbing store.

Another option: "tank in the tank." If you are faced with the question of how to make a boiler with your own hands, take a look at this scheme.

The inner container (in which indirect heating will take place) is selected with corrugated walls (preferably). So more area heat exchange. And the primary heating water flows through the external point. If you cooled a pot with hot compote in a bowl of cold water, the principle of operation of the heater is clear.

Of course, it is more difficult to implement such a system, but the efficiency will be higher.

General rules for the manufacture of indirect heating boilers

A heat-insulating shell is required. Otherwise, the heated water will rapidly cool through the outer walls. The best option is to install the working container in a larger barrel, and blow out the gap between the walls with construction foam.
You can wrap the container with construction thermal insulation materials, though it does not look so aesthetically pleasing (but inexpensive). If the boiler is located in the boiler room, you can save.
The inner pipe (if a serpentine circuit is used) must be corrosion resistant. After assembling the structure, access for maintenance will be difficult.
When using electrochemical couples (for example, aluminum tank+ copper pipe) connection flanges must be insulated with neutral gaskets.
It is advisable to arrange an inspection window in the wall of the outer tank through which cleaning or maintenance is carried out.

improvised materials

We have already talked about stainless steel tanks from old washing machines. However, finding such a blank is not easy. A decommissioned 100 liter propane tank can be an excellent donor. It does not hold pressure (that's why it was written off), but it will still serve as a water tank. Of course, a gas cylinder boiler must be thoroughly cleaned (especially from the inside) and painted with high-quality waterproof enamel.

Not required for manufacturing. industrial equipment. Enough "Bulgarian" and welding machine. The upper part is cut off, then heating fittings are formed in it.

At free access to other materials, you can make a heater even from sheet stainless steel. You can see how to make an indirect heating boiler with your own hands in the video (see below).

Perhaps the aesthetics suffer, but the quality and durability of the made heater is no worse than the factory one.

Electric indirect heater

The use of a heating element does not apply to indirect heating methods, since there is direct contact of water with a primary heat source. The exception is induction water heater. The liquid receives energy as if virtually, without touching the internal thermoelement. Actually, it is not in the design at all.

A do-it-yourself instantaneous water heater is made according to the principle of induction hobs. Only instead of a pot of water, a metal pipe heats up.

The main advantage of the system is that heating occurs not due to direct thermal contact with a source of electrical energy, but with the help of eddy currents. Heat transfer coefficient losses are minimal, efficiency tends to 100%. At the same time, both the metal pipe and the liquid itself are heated (if it is sufficiently thermally conductive). In addition, flow induction heaters are significantly safer than traditional boilers. electric heater: no contact of water with the element connected to the mains.

The disadvantage is obvious: heating requires a connection to the power supply. That is, the option of indirect heating using a wood (gas) boiler does not work. The building must be electrified.

Device diagram and principle of operation

Using a high frequency generator (tens of kHz), an alternating current is generated in the induction coil. According to the laws of physics, at this moment there is a magnetic field with a constantly changing vector. In a conductor affected by magnetic field, random eddy currents occur. The molecules begin to move chaotically and the material heats up quickly.

With the help of such an inductor, you can even red-hot a metal billet. Since water flows through the pipe, there is no excess heating.

The generator can be borrowed from hob(of course, induction), or make it yourself.

Another donation option is an inverter welding machine.

Although, given the simplicity electrical circuit, many home craftsmen make similar generators from available radio elements.

Conclusion

Depending on the power supply of your home and the method of heating it, you can select, develop, and make with your own hands any of the listed indirect heating boilers. The cost of "production" depends on the availability of material and element base.