Connection, installation, installation and piping of a solid fuel boiler. Tying a solid fuel boiler: the correct diagram with a boiler and a heat accumulator How to tie a solid fuel boiler with a closed system

The wiring diagram for boiler rooms for a private house with a heat accumulator and a standard solid fuel boiler is one of the most reliable and popular combinations. The construction of the diagram begins with the placement of the solid fuel boiler piping, as well as the placement of the buffer tank. This element is installed in order to obtain an additional natural circulation circuit. This creates an alternate path along which water will be directed in the event of an unplanned short-term power outage and a sudden stop of the pump.

Let's consider a circuit with natural circulation - gravitational. When drawing up a plan, we avoid bends and try to minimize the number of bends so as not to create unnecessary resistance. Based on the size of the pipes of the boiler used, we select the diameter of the pipes for the circuit. The standard option is no more than 1.5 inches.

The coolant circulates within the gravitational circuit without the help of a pump due to the temperature difference created. If the circulation of hot water stops due to a power outage or for another reason, the solid fuel boiler will boil. To avoid this dangerous situation An additional gravity circuit is used to prevent an accident in the event of a pump stop.

Sometimes the temperature of a solid fuel boiler increases and can exceed the limit of 100 degrees. For this reason, we tie the circuit with metal pipes. We add a pump to the intended circuit. To do this, we are planning a workaround, where we install a safety petal check valve on a dedicated section of the gravity circuit. We select a valve with minimal resistance. An adapter with standard resistance may interfere with coolant circulation.

In normal mode, the circulation pump creates pressure on the valve, keeping it closed. In this case, water circulates freely along the usual path. When the pump stops, the boiler continues to heat the water, but the built-in valve will work and will not allow water to flow through the main circle.

Adding hot water and adding valves

In order for the system to work, it is necessary to ensure automatic addition of hot water to the return line. This way we increase the temperature of the water entering the boiler. If too cold coolant gets into it, the boiler can quickly fail. There are several common piping schemes with the addition of a return line. We use a three-way thermostatic mixing valve. Installing this valve allows you to create a small circle of circulation of the coolant, as a result of which the heating of the boiler will accelerate. This approach prevents the formation of condensation, thereby protecting the heat exchanger from breakdowns due to significant temperature differences.

Let's imagine a simulated situation. We will set the built-in petal valve to operate when the temperature reaches 55 degrees. When the boiler starts, the water in the system is not heated and while it is cold, the valve closes and lets the medium flow in a small circle. After the supply water warmed up to a threshold value of 55 degrees, the valve opened slightly and began to mix in cooled water from the return. At the next stage, the entire barrel is heated, and the return temperature will also rise above 55 degrees. At this point, the valve will switch completely and release water through the large ring.

After connecting the return line to the solid fuel boiler, we add a pressure relief valve. It is necessary in case of exceeding performance indicators. The solid fuel boiler has a special hole for mounting the valve. In other models, the valve can be installed through a tee. We include an expansion tank in the system. After this, to complete the piping on the heat generator side, it is necessary to connect the electric boiler. It is included in the circuit in parallel with an already installed solid fuel boiler.

We have two feeds, and check valves need to be installed on each of them. This is done so that the pump of one of the boilers does not pump water along the working circuit in the opposite direction to the other. Let us remind you that on a solid fuel boiler we use not a regular valve, but a reed valve.

Connecting a solid fuel boiler and buffer tank

The simplest would be a piping scheme containing a buffer tank with a pre-installed DHW coil. The advantage of this option will be significant space saving in the boiler room due to the absence of a separate boiler. Another additional benefit is the modest savings on investment due to the absence of the need to purchase and install another unit. This option simplifies the system maintenance process, since there will be no problems fighting bacteria.

In summer, a heat accumulator with a DHW coil becomes a full-fledged indirect heating boiler. The pump is connected to the circuit as standard inch pipe, a ¾ or inch pipe fits well on an electric boiler. If you plan to install a buffer tank with a volume of at least 1000 liters, then it is more economical and expedient to raise the return from the electric boiler a little and connect the main circuit not from below, but above, to the middle terminals of the heat accumulator. With this scheme, the boiler will not constantly heat the entire volume, which will reduce its depreciation rate. This parameter depends on the terms of reference.

If you need to connect not a solid fuel boiler, but a gas boiler, then the same circuit diagram is used as for an electric one. It should be noted that in the scheme we are considering, a standard electric boiler already contains everything necessary:

• pump;
• pressure meter;
• safety valve.

If you choose a model that does not have these parts, the boiler will have to be tied accordingly.

Connection to the heating system

We connect the prepared circuit directly to the heating system. From a safety point of view, it must be remembered that a solid fuel boiler can produce an excessively high temperature at certain moments. The storage barrel can contain water at a temperature of 90-100 degrees. This is too much for standard home heating radiators. You can get seriously burned if accidentally touched. For this reason, it is necessary to add another mixing valve to the circuit. He will mix cooled water into the circuit.

If the house has heated floors, it is possible to connect them to the radiator circuit for return flow. Another pump will need to be installed. The connection will go to the mixing unit. Due to the high temperature, water is not drawn directly from the heated heat exchanger, but through a safety mixing valve. This part is installed so that when working with the system and checking it, you do not get scalded by hot steam.

At the next stage, we connect the coolant recirculation line in the system through a special pump. We arrange check valves in the circuit in accordance with the diagram. On this full set functional elements are completed, let's move on to the fittings.

Another filter needs to be installed in front of the boilers. Then we install additional automatic air vents at the highest points of the system. Next, we ensure that the system is drained and filled. To do this, we arrange the ball valves so that in the future we can carry out technical inspection and repair of equipment without draining the coolant from the circuit. Cranes are needed for:

• expansion tank;
• boilers;
• pump

In cases where boilers do not have standard thermometers, they are installed additionally. You will also need two control thermometers located on the buffer tank. They will make it easier to monitor the operation of the system and set it up.

Insulation of fittings

Let's consider the issue of the need to insulate the fittings. Long pipe lengths, many fittings and high operating temperatures in the system lead to heat loss. At finished facilities, heating equipment that is not properly insulated overheats the surrounding space. In the room where the boiler and heat accumulator are installed, the temperature can reach plus 27 degrees in severe frost. Fuel is wasted and system efficiency decreases. After insulating the pipes, it is possible to gain several degrees and reduce fuel consumption.

When insulating the fittings, you must remember that when working from the side of the boilers, the pipes become very hot, since they can transport water hotter than 100 degrees. Polyethylene foam insulation is not suitable in this case. It can only be installed in another part of the circuit on the side of the radiators of the heating system. In a boiler room, it is better to put rubber insulation that is more resistant to heat on hot pipes. It is also worth additionally insulating fittings and other fittings.

For safety reasons, it is not recommended to insulate pumps. This equipment is limited to exceed ambient temperature limits. If you insulate the pumps from the boiler side, you can insulate them too much, and this is unacceptable.

Connection diagram with boiler

Let's consider another wiring diagram for a solid fuel boiler, in which in addition to the heat accumulator there is a boiler. We will not redo the boiler part, we will leave it unchanged. Similar to the previous diagram, we will connect the entire heating system. Only the indirect heating boiler added to the planned circuit will be new. Inside the model we have chosen there is a coil through which the heated coolant passes. Thanks to this, the water is heated directly and pumped using a special pump. Based on the experience of previously used circuits, I recommend using the terminals connected to the boiler away from those connected to the boiler itself and heating radiators.

Another expansion tank must be installed at the outlet of prepared hot water from the boiler. After this, we install a petal safety valve at the entrance to the cold water system. According to this scheme, it is permissible to supply hot water directly to the bathrooms without additional inserts. The pipes will not be too hot - the boiler automatically controls the temperature of the coolant inside itself.

It may be useful to put additional mixer at the outlet, since the boiler periodically requires preventive disinfection of the internal cavity at high temperature. When the system heats up, there is a possibility of being scalded by steam if at that moment someone opens the hot water. In addition, the mixer will allow you to leave an increased supply of hot water in the boiler. To do this, the electric boiler must be connected to the boiler, but the circuit will be built directly according to a different scheme.

The recirculation line in the boiler is connected through a special additional output. We connect the fittings to the circuit according to the diagram discussed above. Please note that in the diagrams provided, only the hydraulic part is disassembled in detail, without installing insulation.

Solid fuel boilers do not lose their relevance and popularity. Even with the availability of main gas and electricity, solid fuel is often more effective or more cost-effective for heating a home. To use it, it is useful to familiarize yourself with how to piping a solid fuel heating boiler, a diagram that will work better in the house.

Methods for connecting the boiler to the heating circuit

The composition of the equipment and the boiler piping directly depends on the selected type of heating circuit, the method of circulation of the coolant and the degree of automation of the process, such as fine-tuning the climate or simply adjusting the heating of the coolant.

The task of the entire strapping complex is:

• Ensure uniform heat distribution throughout the heating circuit.
• Protect people and equipment from any emergency situations and minimize the consequences of a breakdown.
• Reducing the influence of frequency in the operation of a solid fuel boiler, since the main power is released only after the next load of fuel is ignited, while as it burns out, the heat transfer decreases.

Automation

First of all, you need to ensure trouble-free operation of the boiler itself. To control the combustion process of fuel (wood, coal or pallets), it is enough to control the supply of fresh air to the firebox. WITH solid fuel boilers this means using automation units based on a controller, thermostat and blower fan in the piping.

In the very simple version A draft regulator will help automate the operation of the boiler. Simple constructive solution, in which a non-volatile thermostat is involved. Depending on the temperature of the exhaust gases or coolant in the heat exchanger, the draft regulator changes the degree of tension of the chain connected to the damper, thereby changing the level of air supply to the combustion chamber.

For full control and automation, one cannot do without including a controller in the harness that can set the optimal operating mode of the solid fuel unit. It relies on data from several temperature sensors and controls the fan that supplies air to the firebox. A solid fuel boiler control kit will cost an average of $25-45 and will provide:

• Adjustment of fuel combustion activity depending on the coolant temperature.
• Saving fuel by avoiding pointless burnout and heat release into the chimney.
• Increasing boiler safety by installing forced draft and controlling the removal of combustion products.
• Automatic shutdown of the boiler when the water in the heat exchanger overheats, preventing rupture or other serious consequences.

However, the automation unit simultaneously makes the solid fuel boiler energy-dependent, therefore for non-stop and quality work you will have to acquire a powerful uninterruptible power supply (UPS).

Composition of mandatory harness

Security group

This implies a standard set of equipment, including:

• blast safety valve;
• automatic air vent;
• pressure gauge

It is advisable to purchase the safety group ready-made, selecting the elements in strict accordance with the heating design and the characteristics of the solid fuel boiler. In this arrangement, the safety group is in demand primarily in closed heating systems, where a consistently high coolant pressure is maintained. How to select a security group is described in this article.

The group is installed in the harness only in compliance with four basic rules:

• directly next to the boiler at the hot outlet;
• the section of pipe from the boiler to the group should be made with the same pipe cross-section, without narrowing and preferably without the use of bends or turns;
• It is unacceptable to install shut-off valves between the boiler and the safety group;
• the group and specifically the air vent are mounted at the highest point of the circuit.

For natural circulation with a closed circuit, the distance from the boiler to the safety group can be several meters, which greatly reduces the effectiveness of the blast valve.

Expansion tank

To compensate for the thermal expansion of the coolant in the heating circuit piping, an expansion tank is used:

• non-hermetic for open systems;
• membrane – for sealed closed heating systems.

In the first case, this can be a container with a volume of at least 10% of the total coolant volume in the circuit. Installed at the highest point of the contour. The installation height also determines the operating pressure of the system. Performs the functions of a security group. The tank is not isolated from the environment and, due to its installation at the highest point, ensures effective removal of air circulating in the pipes. If the coolant expands excessively, excess water enters the tank or is discharged into the sewer when the permissible volume is exceeded.

A membrane-type expansion tank is designed for closed heating systems in which the operating pressure is artificially set at 1.5-2.5 atmospheres. Inside the tank, the space is divided by an elastic rubber membrane into two chambers: coolant enters one, air is pumped under pressure into the second.

An expansion tank is installed at the hot outlet of the boiler after the safety group or at the cold lower connection after piping the circulation pump.

Bypass and selection of distribution pipes

A bypass is a section of pipe connected parallel to any node in the heating circuit. It is needed to reduce the overall hydraulic resistance of the circuit and to be able to control and regulate the volume of coolant entering a separate unit, radiator, storage tank, expansion tank, etc.

With a solid fuel boiler, bypasses must be installed on each radiator and storage tank, without exception, so that a circuit is formed in which the coolant can by default circulate without any obstacles or problems and regardless of bandwidth each individual element.

In addition, it is advisable to install a bypass on the boiler itself. In fact, this forms a small circulation loop in which the boiler is tied to itself.

However, this can only be done if the solid fuel unit is equipped with overheating protection and an automation unit that will prevent water from boiling.

The presence of a small circuit in a system with forced circulation allows you to control the heating of the house without changing the load on the pump and without resorting to fine-tuning the operation of the boiler. Using a three-way valve with a thermostatic head, it is possible to set the target temperature in the heating circuit in a narrow range and hot water from the boiler will flow only when necessary to replenish the expended energy.

Basic requirements for heating pipes with solid fuel boilers:

• The section directly from the boiler along the hot and cold outlets at a distance of up to 1.5 meters is made exclusively of metal, and then, if necessary, a transition to metal-plastic is installed.
• The main piping components (safety group, circulation pump, expansion tank) are mounted with pipes of the maximum permissible cross-section to reduce hydraulic resistance.
• The distribution pipes must comply temperature conditions boiler and heating system with a margin of up to 20%.

Storage capacity

Bypass and a small circuit with a three-way valve allow you to completely solve the problem of adjusting the heating on the radiator side. However, this does not solve the problem with the boiler, which is forced to work intermittently or often turn off due to automatic decisions, after which it will have to be lit again.

The storage tank in the solid fuel heating system is an insulated large-volume tank filled with coolant. Due to the high heat capacity of water, thermal energy can accumulate in the accumulator during periods of maximum heat transfer from the boiler. As soon as the fuel load burns out and the temperature of the coolant in the main circuit decreases, heat begins to flow from the heat accumulator, smoothing out temperature fluctuations. The heat accumulator is installed parallel to the main circuit.

By design they are distinguished:

• pass-through heat accumulators, in which the coolant directly accumulates, increasing the total volume of water in the system;
• batteries with heat exchangers in the form of built-in coils or pipe registers.

Wiring diagram for a solid fuel heating boiler

, for a boiler and boiler in Minsk

Connecting the boiler (installation-piping-installation) is NOT the next stage after purchasing a solid fuel boiler, it is important to decide who will install it and how, decide in advance, and NOT buy a solid fuel boiler without installation, especially in Minsk. After all, having bought it, you can still install it crookedly, and then what is the point of a solid fuel boiler, you should approach it with all seriousness and responsibility. Tying a solid fuel boiler requires specific knowledge, skills and abilities. It is unlikely that you will be able to tie a solid fuel boiler yourself. Yes, and this is a dangerous idea. So, if you still decide to entrust the connection of a solid fuel boiler to a specialist, then our advice: try to understand this process and at least try to understand the nuances of installing the boiler yourself(you will continue to use it for many years and operate the heating system; by the way, a wood-burning boiler is most often used and has more nuances in piping).

Piping is a set of works for connecting equipment to engineering system(boiler piping). There are harnesses: safety harnesses for sports and for industrial mountaineering, strapping of the foundation with boards.

We will try to list some of the nuances when. Installation of heating boilers begins with preparing the floor and removing smoke:

• preparing the ground for installation of a solid fuel boiler- it must be strictly horizontal. Because Since a solid fuel boiler weighs a lot, the floor screed poured under it should be 7-10 cm. The dimensions of the base should correspond to the dimensions of the boiler, increased by 10%.
• also, any heating boiler (except electric) requires connecting a chimney. It can be either indoors (not insulated) and exit vertically through the roof, or initially exit horizontally through the wall and rise along the wall of the house above the ridge (insulated). Any chimney must be cleaned annually and its condition monitored.

How to properly tie a solid fuel boiler

Solid fuel boiler piping requires ensuring certain safety measures for the heating system:

• installation of an emergency valve (or boiler safety group). If the pressure in the heating system rises, an emergency discharge of the coolant into the sewer will occur. And this will prevent the boiler from exploding.
• Installing a cooling circuit on a solid fuel boiler will protect you from the boiler exploding, as well as from the need to recharge the heating system in the case described above.
• connecting a UPS uninterruptible power supply to the boiler and pumps will allow the heating system to operate properly even during a power outage, which we often hear about in the news settlements Belarus.
• connecting a solid fuel boiler According to fire regulations, it is necessary to make only a metal pipe (ferrous metal, galvanized, stainless or carbon steel), any option will do. As for diameters, most often we connect boilers with a power of up to 30 kW with a 1 1/4", boilers with a power of up to 50 kW - 1 1/2", and boilers with a power of up to 100 kW - 2" or 2 1/2".
• in the connection diagram of a solid fuel boiler and, accordingly, when piping a solid fuel boiler it is necessary to provide an expansion tank open or closed type(depending on heating system). The volume of the expansion tank is calculated using a simple formula:

  V tank = V system: 10

  Solid fuel boiler connection diagram requires installing an expansion tank on the return line. This will extend the life of the tank membrane.

• connect a solid fuel boiler(with a power of up to 70-80 kW) preferably not with the help of welding, but with threaded connections. In the future, this will simplify the maintenance of the entire system, and will also allow you to easily replace any failed unit.
• solid fuel boiler connection diagram implies the presence of a thermostatic mixing valve (for steel boilers this is protection against excessive condensate, and for cast iron boilers it is protection against cold return flow, under the influence of which a section of the boiler may burst).

These are just some of the nuances that must be observed when connecting a solid fuel boiler, you need to pay close attention. The safety of a home's heating system is the first place heating design begins.

About price:

Boiler connection diagrams for a general overview

Let's look at the wiring diagrams. Simple boiler piping includes:

• circulation pump(1) to ensure the movement of coolant (water) in the pipes and equipment of the heating system,
• expansion tank(2) takes excess water (coolant) from the system when it is heated and releases it back into the system,
• boiler safety group(3) with a safety valve, when the boiler boils, it throws excess water into the sewer.

Next come the safety systems for people and the boiler itself. We protect the boiler heat exchanger from exposure to excessively cold water, which causes it to fail ahead of time. We put 3 way thermostatic mixing valve(8) - if cold water comes from the return from the heating radiators, which is more than useful for the boiler heat exchanger, the valve will turn on the addition of hot water.

Now we protect people from explosions and burns. A feature of the piping of a solid fuel boiler is: combustion solid fuel in the boiler is completely uncontrollable as with gas and electric boilers. That's why Necessarily to connect the heating system with a solid fuel boiler, prevent excessive overheating of the water to 95 degrees. in pipes and heating radiators to temperatures dangerous for human touch. And for this there are 3 separate methods of cooling water to heating radiators, which can be used simultaneously.

Option 1: Mixing valve(7) as necessary, adds cooler water from the return water from the heating radiators to the pipe to the heating radiators. Looks simple enough.

Option 2: 4-way valve for emergency cooling of heat exchanger(4) with a remote sensor for overheating up to 95 degrees. It will run cold water from the water supply into the boiler through the return line, and throw the superheated water from the boiler into the sewer. Since this is possible when there is a power outage in the house. The boiler pump stops, but also the pump in the well. That's why cold water to cool the boiler it is taken from the hydraulic accumulator of the water supply and it may not be enough: install additional hydraulic accumulator(5) with a check valve (6) to disconnect it from the water supply.

Option 3: Emergency gravity circuit with a check valve (9) - the diagram shows this as an option, however, the circuit requires specificity, a certain low pressure and temperature, and may contain a heating radiator for these purposes.

Option 4: Use several methods at the same time.

Connecting the boiler in the photo

Solid fuel boiler piping

Solid fuel boiler connection diagram

The piping of a solid fuel boiler with a connection to a closed circuit of the heating system necessarily contains a boiler safety group, an expansion tank and a circulation pump. Solid fuel boilers do not have a number of safety functions; therefore, the piping of a solid fuel boiler must additionally include the specified safety systems. Safe connection of the boiler is the safety of life and health of household members and must ensure the minimum operating temperature of the coolant at the entrance to the boiler at a level of at least 60°C. The heat exchanger should not be subject to large thermal changes - this will prevent unwanted metal deformations and the formation of tar and soot in your boiler. This condition is ensured by the installation of a mixing unit. It will maintain the required coolant temperature at the inlet to the solid fuel boiler.

Installation of solid fuel boilers and piping of a solid fuel boiler must be carried out exclusively by specialists. Installing a solid fuel boiler yourself is extremely dangerous, especially since such a boiler installation will most likely not be accepted by firefighters. This material on how to connect a solid fuel boiler is intended to introduce you to the topic so that your choice and control of installation specialists is more competent.

Photo heating installation - Minsk region, Dzerzhinsk

Heating installation: Minsk - diagram drawing, Dzerzhinsk - boiler piping on site, chimney installation. Yes, we start by drawing in pencil a diagram of the future heating system of the house with real heating equipment: solid fuel boiler SAS 58 kW,

The installation of a solid fuel heating boiler in the photo was carried out by Boiler House Bai, Minsk.

Also photo:

Connecting a solid fuel boiler with a heat accumulator (buffer tank) on video

In the video, Sergei Nikolaevich, chief engineer of the House of Boilers, Minsk, begins connecting a solid fuel pellet boiler with a heat accumulator with simple truths.

Installation of a solid fuel boiler, installation of a solid fuel boiler, piping a solid fuel pellet boiler with a heat accumulator, answers to the question which boiler is better and what heating equipment to buy- our entire website of the online store House of Boilers by, Minsk is dedicated to all these topics.

Here on the website of our online store House of Boilers Minsk you can choose and buy heating boilers gas, solid fuel or electric, as well as various heating equipment - boiler, water heater, heat accumulator, buffer tank, heating radiators, chimneys, pipes, comb and heated floor - see our online store in Belarus "Boilers and home heating" price and availability . We will fulfill according to your order necessary work- see Heating installation, boiler piping, installation of heating equipment in Minsk and throughout Belarus, including turnkey.

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The boiler piping represents all the devices and elements that are connected to the heat source, and which together form one heating system. The wiring diagram for a solid fuel device consists of:

1. Shut-off and control valves.
2. Control and automation devices.
3. Pipelines.
4. Heating devices (radiators, heated floors, heated towel rails).

Harness requirements

Tying can be done according to many schemes, which must take into account the rules:

1. Temperature of water or any other liquid, which comes out from the head unit of the system, should not exceed standard values. This concerns the pressure under which the coolant is supplied.
2. Temperature entering the boiler long burning coolant should not be less than 20 °C from the same indicator of the water leaving the heat exchanger. Otherwise, it starts in the middle of the body.
3. There must be automatic devices that can control the power of a long-burning unit and ensure a stable liquid temperature.

Such requirements are best met in schemes that provide for the presence of circulation pumps.

Open system with natural circulation

This scheme is the simplest among all the harnesses because it consists of a minimum number of elements. Thanks to this, it is completely autonomous. Flaws:

1. It is impossible to regulate the temperature of the water leaving the heat exchanger.
2. Air can enter the coolant through an open expansion tank. This accelerates the corrosion of panel and bimetallic radiators, steel pipes and heat exchanger.

This type of harness includes:

1. Long burning boiler.
2. Heated water supply line.
3. Open expansion tank.
4. A certain number of heating radiators.
5. Return water supply line.

Installation rules:

1. The water supply pipe from the boiler must be more than 0.5 m below the heating radiators. Otherwise, the natural circulation of the coolant will be unstable.
2. The pipes are installed inclined in the direction of water movement. To reduce movement resistance, it is recommended to use larger diameter pipes.
3. The expansion tank must be installed in the place whose height is greatest when compared with the height of all the trim elements.
4. Since shut-off and control valves reduce the flow area of ​​pipes (this increases fluid resistance), their quantity should be minimal.

Read also: Frequent breakdowns of electric boilers and their repairs

Closed system with natural circulation

This piping of the pellet device involves the use of a closed-type membrane tank. It is best to place it on the return pipe at the lowest point. In this case, the optimal tank is one that holds more than 10% of the water used in the entire system.

The composition of the scheme is presented:

1. Heating boiler.
2. Security group.
3. Heated liquid supply line.
4. Heating radiators.
5. Membrane tank.
6. Return water supply line.

The safety group is a separate device, which must consist of at least radiators and a safety valve. The latter is connected to the sewer using a drain hose. Its function is to relieve excess pressure. This device may include a pressure gauge that allows you to visually assess the pressure in the system.

The first two elements of the security group can also be installed separately. Often it is already included in the design of the device. The rules for installing the main piping elements are almost the same as the rules for installing the components of the above-described scheme.

Forced circulation piping

It has almost the same structure as a closed system with natural coolant movement. In this case, an additional element appears in the form circulation pump. In most cases, it is mounted on the return supply line after the membrane tank and in front of the inlet fitting of the heat exchanger.

Thanks to this pump, you can more flexibly control the operation of the system. It becomes possible to install shut-off and control valves on each radiator. Now, under the pressure created by the circulation pump, water is able to easily pass through narrower sections of the polypropylene pipeline.

The use of such a pump makes the system dependent on power supply.

System with collectors

Such piping of a solid fuel unit includes:

1. Solid fuel boiler.
2. Security group.
3. Supply line manifold.
4. Heating radiators.
5. Heated towel rail.
6. Underfloor heating system.
7. Return manifold.
8. Membrane tank.
9. Circulation pump.

Read also: Solid fuel boiler with hob

New elements in this system are collectors. Known as combs. They are a wide pipe with a large number of pipes. One of them is input, the rest are output. A pipe with a safety group is connected to the first. Hot liquid is supplied through it, which, coming out of various pipes, is distributed between user groups: radiators, heated floors and heated towel rails. The second manifold collects the water together and directs it through the outlet pipe.

System with hydraulic arrow

Very similar to the circuit with collectors. Instead of two collectors hydraulic arrow is used, which is a vertical pipe with a large diameter, and which is connected to the supply and return lines. It has many fittings to which individual groups of users are connected.

The pipes to which you can connect radiators, heated floors, etc. are located at different heights of the hydraulic arrow. In this case, the placement height corresponds to the water temperature. Thanks to this, coolant at a certain temperature can be supplied to various devices.

System with heat storage

The piping of a solid fuel heating boiler, the diagram of which includes, differs in that it can have two coolant flow circuits:

1. The first occurs between the device and the heat accumulator.
2. The second is formed between the heat accumulator and radiators.

The scheme is as follows:

1. Boiler.
2. Security group.
3. Heat accumulator.
4. Heating devices.
5. Main circulation pump. It is included in a pipe that extends from the heating radiators and goes to the heat accumulator.
6. Membrane tank. Located after the heat accumulator.
7. Additional circulation pump. It is located between the membrane tank and the return pipe of the heat exchanger.

It accumulates heat in itself, simultaneously releasing the required amount of it to the radiators. It always supplies a normalized amount of heat, absorbing all its excess. As a result, the radiators do not overheat. In this mode, the coolant circulates throughout the entire system.

If you need to stop the supply of heated water to the radiators for a while, it begins to circulate between the boiler and the heat accumulator. When the fuel in the boiler runs out and the fire goes out, the coolant circulates only between the heat accumulator and the heating radiators.

Connection diagram for a solid fuel boiler and a gas boiler

Very simple is the harness, which provides parallel connection of a gas and solid fuel boiler. It is used for systems with natural circulation.

If the piping of a solid fuel boiler is done correctly, this significantly affects the service life of the heating equipment, prevents emergency situations, and ensures stable operation of the heating system. Connection diagrams may vary, but there are general installation principles that must be followed during installation of the water circuit.

Solid fuel boiler piping options

1. Coolant circulation type.
2. Type of heating system.
3. Simultaneous use of radiator heating and underfloor heating systems.

Based on the type of coolant circulation, it is customary to distinguish the following schemes:


In addition to the distribution of systems according to the type of coolant circulation, it is customary to divide several more schemes according to a similar criterion:


Based on their design or connection principle, it is customary to distinguish several more common heating schemes:


There are modern piping systems for solid fuel boilers using a hydraulic arrow and a manifold group. Such solutions are used if it is planned to connect water circuits using the principle of high and low temperature heating. The hydraulic arrow is installed in a heating system with heated floors.

When choosing a heating system with a solid fuel boiler, focus on the following points:

1. Cost of strapping work.
2. Thermal characteristics of the room.

When making calculations and choosing a suitable piping scheme, you cannot do without competent advice from a heating engineer.

Piping diagram without a heat accumulator

• After turning on the boiler, the heated coolant circulates through a small heating circle. The three-way valve prevents cold, unheated water from entering the heat exchanger. A large difference in the supply and return temperatures leads to the fact that the boiler begins to “cry”. A large amount of condensate forms, which negatively affects the heat exchanger.
• The coolant gradually warms up and after heating above 60°C, the three-way valve opens. From this moment, a large circle of the heating system begins to work.
• The small circle of the heating system continues to function as a mixing unit, preventing boiling of the coolant, and reducing the gap between the supply and return temperatures.

Connection with an indirect heating boiler

A simple connection of a solid fuel boiler with a heat accumulator tank replaces a small heating circle and is done as follows:

• The container is installed between the boiler and the heating system.
• The supply pipeline is connected to the upper part of the boiler, and the return pipe of the system is connected to the lower part.
• Two circulation pumps are installed on the return line. Performance pumping equipment should be different. The settings are set in such a way that the coolant in the buffer tank moves from top to bottom. This can be achieved by placing a circulation pump of greater capacity in front of the storage tank, and a smaller one after it.

Connecting a solid fuel boiler with an indirect heating boiler performs several important functions:

• Reduces the temperature difference between the supply and return of the heating system.
• Allows you to accumulate the resulting heat and add hot water to the heating system after the wood in the boiler has burned out.

Connecting the heating boiler together with the electric boiler

Tying is done as follows:

• Two boilers are connected in parallel.
• The electric boiler has a circulation pump installed. For a solid fuel unit, you will need to install pumping equipment.
• To prevent the occurrence of a duplicate coolant flow, when two circulation pumps are turned on simultaneously, a special valve is installed to block the flow. In this case, a check valve in the heating system is needed so that when two boilers are operating simultaneously, the coolant does not stagnate in the boiler circuit. You will need to install two fittings. One valve is installed on the supply pipeline from the electric boiler, the second, on the return line going to the solid fuel boiler.
• The functionality of the system will be ensured by two temperature sensors. The room sensor is connected to the electric boiler. When the temperature in the rooms drops below the set minimum, heating of the coolant using electricity automatically starts. To prevent heat loss, a temperature sensor is also installed on the boiler heat pump, which turns off the circulation of the coolant when the combustion chamber cools down.

Which pipe to use for piping a solid fuel boiler?

A section of a small heating circle is made using metal piping (steel, copper). This is done so that when the coolant boils and emergency situation, the pipes did not deteriorate and retained their tightness under the influence of high temperatures. The material of the rest of the pipeline can be chosen as desired.

The most common strapping options are:


Due to the fact that heating of the coolant often reaches the boiling point of the liquid, tie the solid fuel boiler better pipes made of metal. But, since this option is not always possible, the use of analogues is allowed. The use of polypropylene with fiberglass in heating systems with a solid fuel boiler has proven to be one of the most reliable and optimal piping methods.

How and with what to insulate pipes

PET pipe protects against mechanical damage. The insulation is a kind of protection against condensation, preventing burns from accidentally touching the pipes, and also reducing heat loss. Fix the insulation using clamps or binding wire.

Necessary units and components for piping the boiler heating system

• Thermostatic or thermomixing valve– necessary to stabilize the heating of the coolant and prevent overheating and boiling of the latter.
• Expansion tank– provided in any heating scheme. The membrane expansion tank is installed in closed systems with forced circulation of coolant. In gravity schemes, an open container is installed at the highest point of the water circuit.
• Circulation pump– installed in closed and open systems with forced circulation of liquid in the water circuit. Some solutions, such as the use of a buffer tank or two parallel-connected boilers, require the installation of two circulation equipment modules at once.
• Check valve - coordinates directionality heat flow liquids. Used when connecting a membrane tank. Prevents the occurrence of duplicate flow when connecting electric and solid fuel boilers at the same time.
• Collector - used when simultaneously connecting heated floors and radiators. You cannot do without a collector when making a radiant heating system, when each heating device has its own separate pipeline. A manifold in a heating system is needed for most modern circuits heating
• Air extractor– automatic valve included in the standard safety group. In automatic mode, it bleeds air from the heating system.
• System make-up valve– controls the pressure and total volume of coolant in the system. When it falls below the minimum value, it opens and replenishes the water circuit with liquid.
• System pressure sensor– also included in the security group. Shows the nominal pressure in the heating system, often the first to indicate overheating of the coolant. By checking the readings of the thermometer and the pressure sensor (manometer), it is convenient to set the required operating mode and configure automatic.
• Coarse filter– installed on the return line, directly in front of the circulation pump. It is recommended that the filter be installed in front of the buffer tank, expansion tank and other sensitive elements of the heating system.
• Hydraulic boom– a hydraulic arrow in the heating system, needed for boilers that use the principle of long burning and modulating power settings. In practice, this device replaces a buffer tank and has general principle work.
• Mixing unit or mixing unit– mixes hot and cooled water from the heating unit to prevent boiling and reduce the difference between the coolant supply and return.

Methods for protecting the boiler and heating system from overheating

• Small heating circle– initially, the circuit prevents condensation. After the large heating circle has started working, the structure plays the role of a mixing unit.
• Security group– includes an air vent, pressure gauge and pressure sensor. If there is excessive overheating, the pressure in the system increases, which leads to the valve breaking off and releasing a certain amount of water from the water circuit.
• Diaphragm tank - pressure in the expansion tank in closed system heating of a solid fuel boiler varies depending on the heating of the coolant. The capacity is selected based on the total volume of coolant, using special formulas. The pressure in the heating system should be no more than 2 mbar. Most heat exchangers of TT boilers cannot withstand high parameters and become deformed when overheated.
• Buffer capacity– connecting a solid fuel heating boiler to the heating system through a storage boiler makes it virtually impossible for the coolant to boil.
• Connecting the circulation pump– when there is a power outage, the movement of the coolant stops, which leads to almost instantaneous boiling. Safety regulations require the pump to be connected via power.

The optimal volume of the heating system is calculated using the formula, 1 kW = 15 liters of water. The result obtained is used when selecting an expansion membrane tank or determining required quantity coolant / antifreeze.

What is better to pour into the heating system when heating with a solid fuel boiler?

• Type of building - in heated rooms, it is more advisable to use ordinary water as a liquid for the heating system.
• If you plan to heat the building from time to time, it is better to use non-freezing liquid.

The choice of piping for a solid fuel boiler affects the safety and service life of heating equipment. Calculation of the heating system requires the involvement of a qualified heating engineer.