The growth in the volume of individual cottage construction has caused a stir in the heating equipment market, because it is impossible to create a comfortable living environment in a house without a reliable heating system and hot water supply. Many residential areas are equipped with a main gas supply, so their residents buy reliable gas heat generators. Experts believe that a good source is only part of success, and the key to it is the proper piping of the gas boiler, which will protect thermal system from water hammer and will provide comfortable heating of the house.
Piping is a set of engineering works to combine elements and units of a thermal circuit into a single heat-generating complex. Its executive design is absolutely individual and depends on the type of boiler, the number of heating circuits, safety automation, wiring of the in-house heating system and hot water supply.
All main and auxiliary gas boiler equipment belongs to objects with increased danger; even the smallest errors in the piping lead to irreversible processes and can cause an emergency and fire hazard in life support systems. In this regard, it is important to approach the piping of a gas boiler responsibly, observing standards and safety regulations regarding the installation and operation of gas boilers low power. That is why it is recommended that all work on the design, installation and commissioning of gas boiler equipment be entrusted to certified personnel.
Boiler piping functions:
- Uniform distribution of heat and speed flows throughout the heating and hot water system.
- Compensation for thermal expansion of pipeline systems and hot heating surfaces (boiler, boiler).
- Removing air from the water coolant.
- Monitoring the medium pressure and releasing water, if the maximum threshold is exceeded, through the expansion tank.
- Creation of a specified mode in the gas-air path of the boiler.
- Maintenance sanitary temperature internal air in a heated facility.
Main components and elements of the system
The piping is associated with specific equipment and components of the heat supply circuit and depends on the connected thermal power of the facility. There are standard installation projects that can become the basis for the development of specific activities.
Equipment included in the gas heating boiler piping scheme:
- Gas boiler units are a heat source, they differ with natural or forced circulation, single or double circuit, wall or floor.
- Air vent - to remove air pockets from the heating circuit.
- Mud collector is a container for collecting and purifying suspended substances in network water.
- A membrane expansion tank to protect the system from excess pressure and water hammer during ignition of the device and reaching operating temperature parameters.
- Softening filters – for purifying water from hardness salts.
- Branch pipes – for connecting incoming and outgoing heating pipelines.
- Sensors, pressure gauges and thermometers - for connecting control and safety automation.
- Flues and chimney - for removing spent combustion products into the environment.
- A gas filter for purifying gas from impurities is installed behind the gas tap.
- Pumps, smoke exhausters, fans - to ensure the movement of water and gas-air media.
- Heating radiators are devices with the help of which heat exchange occurs between the temperature of the coolant and the air inside the room.
Rules for piping a gas unit
Before you start purchasing equipment you need to get Specifications and permission to connect to the gas pipeline. The gas service determines whether it is possible in principle to install a gas boiler, as well as the gas parameters at the insertion point. Next, the owners carry out a heat supply project with the involvement of a specialized organization, which will necessarily indicate the piping diagram. This project is being coordinated with the gas service. Usually this takes from 2 weeks to 3 months, only after that you can buy gas equipment.
Basic Rules:
- Before you begin piping a gas boiler for heating, it is installed in a room that must have minimum parameters: an area of at least 4 m, a height of 2.5 m, and a doorway width of at least 0.8 m.
- The room must be natural ventilation and windows, the sizes of which depend on the area: 0.3 m2 of window per 10 m2.
- All gas pipelines must be made of steel.
- The chimney pipe should have a diameter, depending on the boiler power: 30 kW - 13 cm, 40 kW - 17 cm, but it should not be smaller than the smoke outlet pipe from the boiler.
- The outer part of the chimney must be at least 50 cm higher than the roof.
- A gas sensor and a gas shut-off valve are installed in the boiler room.
- The boiler equipment must be reliably grounded.
- The power supply system is equipped with current protection and thermal insulation.
- The piping of the elements of the working circuit is carried out using pipelines, which can be made of galvanized steel, cast iron, copper and plastic.
- The sections of pipes at the outlet of the boiler are made only of metal, with a length of at least 1.0 m.
IN Lately The most popular are metal-plastic pipes with press fittings and polypropylene pipes with aluminum reinforcement. Their advantage is undeniable, both in terms of reliable, quick assembly, and in terms of cost; in addition, such a pipeline can withstand pressures of up to 25 bar and ambient temperatures of up to 95 C. However, the options also have disadvantages that must be taken into account when starting installation. Press fittings are very sensitive to the quality of assembly; at the slightest misalignment, water leakage can occur, and polypropylene has a high elongation coefficient at temperatures above 50C.
Features of piping gas boilers with polypropylene:
- Heating and hot water circuits are made with: PN 25 (2.5 atm, 95 C) and PN 20 (2.0 atm, 80 C) pipes.
- The connection of pipes and fittings is carried out by cold or hot welding, for connection with metal areas threaded connections are used.
- To avoid destruction of polypropylene pipes, compensation loops are installed.
- Multilayer pipes have internal reinforcement for compensation. Foil reduces elongation by 2 times, and fiberglass by 5 times.
- Before welding, remove foil from reinforced pipelines.
Options for strapping schemes
The classic version of piping a gas boiler is when the coolant rises through the supply, enters the risers and then onto the radiators. The degree of heating of the room depends on the amount installed radiators equipped with chokes and jumpers. The cold coolant is returned to the boiler via the lower return line.
The most common strapping schemes currently are:
- Gravity system;
- forced with circulation pump;
- single-circuit;
- double-circuit;
- wall-mounted boiler;
- floor installation of the unit.
Strapping in gravity systems
The gravitational heating scheme is allowed for the implementation of heat supply to objects with an area of no more than 100 m2 and must be carried out exactly as designed. If there are errors when choosing pipes, or the slopes are not maintained, the system will not work.
The operating principle of the system is based on the difference specific gravity hot and cold water. The hot water rises to the radiators, where it gives off heat to the surrounding air, then the cooled cold coolant goes down and through the return flow enters the inlet of the heating boiler. The main condition for piping is to ensure pipe slopes of at least 3 degrees.
Advantages of the scheme:
- Simplicity of design;
- accessibility of installation;
- quiet operation of the boiler;
- long service life.
As disadvantages, users note:
- Long heating period;
- the inability to accurately regulate the temperature inside the room air;
- the rough appearance of installing pipes with slopes that interfere with the interior of the premises.
Connecting systems with a circulation pump
Circulation pumps are included in the circuit in a system with high resistance when they cannot be overcome using natural circulation or in double-circuit boilers, where the coolant alternately enters the heating or hot water circuit. The pump increases the rate of circulation of the medium through the boiler system, and therefore the efficiency of the heating system increases by 30%. In addition, the fact that such a scheme is easier to automate and allows for finer adjustment of the thermal regime in the premises is positive.
Installation of the pump on the network pipe is carried out using union nuts; most often they come complete with the boiler, but can also be purchased in the retail chain. When installing the unit for pumping network water, it should not be subjected to forces when tightening the nuts. A dirt filter is installed at the inlet of the pump to protect the impeller of the unit from dirt and deposits. The pump is isolated from the main equipment by ball valves for repair and maintenance.
The nuances of strapping
Despite the fact that the harness is selected individually, there are several general provisions that must be adhered to:
- The boiler for schemes with natural heating circulation is installed below the level of the radiators.
- The base for installing floor-standing units must be made of non-combustible materials.
- Boiler rooms are equipped with ventilation and lighting.
- The boiler unit is connected with the inclusion of a coaxial chimney.
- After assembling and installing the unit and smoke ventilation systems, a safety group is installed: a control pressure gauge, a pressure relief valve and then an air vent.
- The expansion tank is installed between the hydraulic switch and the boiler unit.
Connecting a wall-mounted boiler
This type of boiler allows installation on the wall in the kitchen. Structurally, it is made in such a way that the necessary piping has already been carried out by the manufacturer, and its elements are supplied as a kit. Depending on the type of unit, they can be single or double circuit, so the number of pipes for piping may differ.
Algorithm for piping a double-circuit gas boiler:
- Remove the plugs from the pipes.
- Install a strainer on the return line to remove dirt and suspended solids.
- A filter is installed to purify water from hardness salts; it can be installed on the common tap water inlet.
- When piping a wall-mounted gas boiler, shut-off and control valves with detachable connections, for example, “American” ones, are installed.
- The cold water pipes are located on the left side relative to the center of the boiler, and the hot water pipes are located on the right.
- The boiler is connected to the gas mains with the involvement of a certified specialist; the final approval of the boiler will be issued by a representative of Gorgaz after a test run of the boiler equipment.
- When piping a double-circuit gas boiler, the threaded gas connections are sealed only with tow.
- Install a special filter on the gas shut-off valve.
- The boiler is connected to the gas main with a corrugated hose and a union nut with a paranitic gasket.
Connecting a floor-standing gas boiler
This scheme requires a separate room to house the boiler, since floor-standing models are large and often have an open firebox design that works with natural circulation through the gas-air path. Also included in the scheme is a pump for coolant circulation, especially for piping a double-circuit gas boiler and for a multifaceted heating level: number of floors, different types heating – radiator and “warm floor”.
The circuit for dual-circuit heating (heating and domestic hot water) consists of 5 pipes: 1 - gas, 4 - water coolant. The first is connected to the burner device with a ball valve.
Connection diagram for water coolant when piping a floor-standing gas boiler:
- Heating boiler inlet;
- heating boiler output;
- DHW heat exchanger inlet;
- output of the DHW heat exchanger.
The distribution of water flows is automatic, performed by a three-way tap, hydraulic boom or balancing valves.
For piping a floor-standing gas boiler with extensive heating networks and a long distance, it is recommended to connect 2 collectors with an autonomous pump, for example, one for low-temperature coolant up to 50 C for a “warm floor” system, and the other up to 90 C for conventional radiators.
To reduce the temperature, the manifold can be equipped with a mixer or a three-way valve with a servo drive installed between the supply and return on the comb. Sensors allow you to install different temperatures in the contours.
Thus, in order to properly tie a boiler you will need not only experience installation work, but also strict compliance with state operating rules and manufacturer’s requirements.
A heating boiler is a device in which fuel is burned and a coolant liquid is heated. Heat still needs to be supplied to the water circuits of radiators, heated floors, boilers, etc. Here you definitely need a piping diagram for the gas heating boiler - everything that connects it to the appliances in the premises.
Purpose of the strapping
- Maintaining stable coolant pressure in the system.
- Removing air from a liquid that interferes with its circulation. When an air lock forms, the passage of water through this place stops. IN correct scheme air vents are installed.
- Cleaning the coolant from contaminants. Mechanical impurities impair the performance of equipment. In this regard, it is necessary to install filters for cleaning.
- Compensation for thermal expansion of liquid. To prevent the liquid from destroying the system due to excess pressure, a tank is installed to compensate for expansion.
- Connecting one or more circuits to the system.
- Accumulation of hot water with a connected boiler.
The simplest circuit with one circuit
The simplest wiring diagram for a gas heating boiler is drawn up in accordance with its characteristics and requirements.
The piping also includes connecting the gas supply to the burner.
Gas heating boiler wiring: diagram, photo
The simplest single circuit system is designed according to its characteristics and requirements. Install on the supply side check valve and a ball valve.
A pump is installed on the return or discharge pipe to create liquid circulation, ensuring uniform distribution of the coolant throughout the rooms. A mesh filter is connected in front of it, located downwards with a sump. Before the liquid enters the boiler, it is advisable to install a fine filter.
A closed expansion tank is installed closer to the boiler. It contains a membrane that allows you to relieve excess pressure during thermal expansion of the liquid.
After the pump, the coolant flows through the circuit to the radiators. More modern is the decoupling through a collector - a special water collector from which liquid is distributed through several circuits. It is placed in a separate cabinet, from which the coolant is distributed through pipelines.
The gas heating boiler piping circuit contains a safety valve. When the coolant boils due to overheating, the expansion tank may not be able to cope with the pressure surge. The consequences may be as follows:
- pipeline ruptures and connection leaks;
- destruction of fittings and pipes;
- explosion of the boiler tank.
Install as close to the boiler as possible, because pressure begins to build in it.
On some units, safety groups are installed, consisting of a relief valve and a pressure gauge. The devices are mounted directly into the water jacket of the boiler, but can also be installed on pipelines. On gas and electric boilers these devices can be replaced with others, where when the critical temperature of the liquid is reached, the burners or electric heaters are turned off.
There are many options for equipment for boilers, but the basis of the classification is the division into natural and forced circulation.
Natural circulation
The principle of operation is based on reducing the specific gravity of water when heated. The hot liquid is forced upward by the cold liquid, passes through the heating devices, gives off some of the heat and returns to the boiler for heating.
Installation of inlet and outlet pipes is carried out with a slope of at least 3 0 so that natural circulation occurs and less air accumulates in the system.
With natural circulation, the piping of a gas heating boiler (diagram below) is done so that the radiators are located above the supply pipeline.
The return line goes from above also with a slope. At correct installation and the choice of pipe diameters, natural circulation is almost as powerful as forced circulation.
Advantages of the method:
- simplicity of the system;
- ease of installation;
- quiet operation;
- durability.
The system is suitable for heating small house with a total area of premises not exceeding 100 m2. Disadvantages include the length of time it takes to warm up rooms and the inability to regulate temperature in individual rooms.
Gravity scheme applied for the most part in small houses and in the country, with only one heating circuit. Numerous pipes spoil the interior if they are not hidden in the walls.
Forced circulation
The method has become most widespread, since the pump intensively pumps coolant through the system and heating efficiency increases by 30%.
Advantages also include the ability to regulate temperature and low pipe consumption during installation. The system will still cost significantly more, since it is more complex and requires more devices. Installed items require balancing, and the entire system requires regular maintenance. In addition, a source of electricity is required.
If you install a combined system, it will combine the advantages of both previous ones. It can be switched to any mode using a bypass installed with the pump. In this case, the heating operation will not depend on the supply of electricity to the house.
Polypropylene strapping
Plastic pipes have replaced metal pipes everywhere, including for water pipes. For heating, multilayer reinforced products are used that can withstand high pressure. Thanks to soldering connections, a monolithic piping of a gas heating boiler with polypropylene is obtained. Schemes are created of any complexity and in a short time.
Important! The simpler it is, the more reliable it is, and the higher the performance.
Unlike the coolant, gas is connected to the boiler through a metal pipe with a seal that is hermetically sealed and does not burn.
Piping of a floor-standing gas heating boiler: diagram
The dimensions of a conventional floor-standing boiler are small, but installation together with the piping requires a lot of space. All equipment, including a circulation pump, elbows, bushings, manifold, taps and instruments, is difficult to place compactly.
Most models are single-circuit, and hot water requires a boiler with all connections.
The hot water supply system requires a separate pump (if there is no central water supply), and a thermostatic mixer.
Gas must be connected to the boiler correctly. For this purpose it is ordered project documentation, which is compiled by specialists. Entering the house gas pipe is carried out in the presence of a shutdown device in the event of an emergency. Gas is connected by special services that use special pipes, hoses and other equipment.
Installation of a wall-mounted boiler
Boilers can be hung on the wall even in the kitchen. They take up little space. The wiring for a wall-mounted gas heating boiler (diagram below) is included in the kit and can even be built into the boiler. Compact arrangement of equipment required less space, But similar models more difficult to maintain.
The disadvantage of wall-mounted boilers is their low power. In addition, the devices do not operate without electricity, and natural coolant circulation is rarely used for them. On the other hand, almost all boilers are already equipped with electronics and require electricity. In places with unstable power supply, you can install an uninterruptible power supply.
In the majority wall models There is a connection for a double-circuit gas heating boiler, the circuit of which allows you to supply the house with hot water.
The disadvantage of the dual-circuit option is that the heating is turned off during hot water consumption. This is especially noticeable when the boiler power is low. If there is enough of it, the temperature of the coolant drops by only a few degrees in a couple of hours. This applies to houses with high-quality thermal insulation and a sufficient number of radiators with thermal inertia.
Conclusion
The piping diagram for a gas heating boiler is drawn up in accordance with its characteristics and requirements. For a dacha, a natural circulation system through one circuit is suitable, and for a large house - with a forced and multi-circuit one.
The task of the heating system is to create a comfortable microclimate in the house. Competent organization heating determines the uniform distribution of heat around the perimeter of the living area, and protects the elements of the functioning unit from overheating. Boiler piping is the process of connecting equipment to hot water supply and distribution networks in accordance with operating standards.
Boiler piping components
Boiler - rod heating circuit and its type influences the choice of strapping scheme. The main rule for installing a floor-standing boiler comes down to prohibition of its placement in the upper part of the pipeline distribution A. If the standards are violated, the boiler, which does not have conditions for air exhaust, will begin to create air pockets. The pipe leaving the boiler without an air vent must have clear vertical position.
The pipes located at the bottom of the unit will “tell” about the presence of an automatic air vent necessary for connection to the heating network. They are provided in wall-mounted electric and gas models. This feature should be taken into account when piping the boiler, since wall-mounted monoblock models can independently cope with the release of air masses.
Boilers are sold both fully equipped and without additional elements. Required Parts must be purchased separately and included in the circuit. Those who have chosen heating with natural circulation will not find them useful.
Diaphragm tank and radiators
A paronite gasket will do. The use of tow, fum tape and rubber components is prohibited. They can catch fire, and the rubber will reduce the diameter of the pipe, which will disrupt the gas supply. Such a pipeline initially claims to be in long service, is able to withstand pressure exceeding 25 bar and a coolant of 95 degrees.
Features of connecting solid fuel boilers
Boilers of this type do not have the function of regulating the heat supply. The combustion of fuel cannot be interrupted, therefore, in the event of a power outage, the pump responsible for the forced movement of the coolant will stop. However, heating will continue and pressure will increase. Evolving process will destroy the entire system. To eliminate such moments, several types of emergency circuits are provided that allow you to dump excess heat. This:
- Timely supply of cold water.
- Connection batteries to the pump.
- Presence of a gravity circuit.
- Additional emergency circuit.
For solid fuel boilers, the piping plays important role- a high-quality connection will allow you to create a self-regulating system. Therefore, it is better to trust the subtleties of installation skillful hands specialists.
Gravity heating
It is necessary to pay attention to the principles of coolant circulation through the heating circuit. This - - natural movement coolant and forced circulation circuit. Distinctive feature of these types is the presence or absence of a node that forces hot water to move.
In a natural circulation system, movement in closed system occurs under the influence of the laws of physics. The process is determined by the difference in water density. This type of heating eliminates the consumption of electricity.
Natural circulation system cannot be automatically adjusted, and this will require pipes with large diameter, which will affect the interior of the room and greater cost. If the network is subject to periodic voltage fluctuations, the best option This is exactly how the heating will be organized. The system is reliable in operation and does not require attention. The natural movement pattern is suitable for small area, although now considered "last century".
Advantages of a natural circulation system:
- Easy to install.
- Independence from electricity supply.
- Budget option.
- Reliable operation and operation.
Forced heating system
Forced circulation ensures the creation of the necessary pressure and the account of the operation of electric pumps. The forced circulation circuit is comfortable because it is controlled automatically provided there is a stable power supply. It is permissible to select separate temperature parameters for each room, sensor-controlled systems.
Flaws systems:
- Complex strapping scheme.
- Inevitable balancing of parts.
- Expensive service.
- High cost of components.
Any installation system requires a certain number of additional parts. The installation option on primary-secondary rings does not imply a large presence of fastening and connection elements, but instead of them, installation of pumps on heating rings will be required. The ring system together with the floor boiler are complemented combs- heating collectors , evenly distributing the supply of coolant to the heating elements.
Schematic diagram of the strapping
Heating efficiency depends on the accuracy of the connection. The general wiring diagram for boilers of all types, including solid fuel and condensing types, is simple and looks like this:
- Radiator.
- Nuts " American women» - for attaching the boiler to the heating system.
- Ball Valves- to disconnect the boiler from the system.
- Filters for cleaning - protect against non-standard water fractions.
- Thermal heads, tees, Mayevsky taps
- Angles and tees.
- Valves: straight through, separating, air and safety.
- Expansion tanks.
- Pressure gauges, thermometers, hydraulic separators, circulation pump.
- Clamps and other fastening parts.
Double-circuit boiler
Now let's look at the difference between the heating scheme country house using a double-circuit boiler.
A unit of this type differs from a single-circuit analogue in its universal purpose: it maintains the temperature regime of the coolant in the heating circuit, and heats water for household needs. Single-circuit generators can also indirectly heat water. The process of heat transfer occurs during the passage of the coolant through the secondary heat exchanger.
The difference between a double-circuit boiler is direct transfer of thermal energy to water. Its peculiarity is that when hot water is consumed, the coolant does not heat up. Parallel operation of two circuits is excluded. Practice has shown that for houses with high-quality thermal insulation, and therefore with thermal inertia, the operating mode of the boiler is not important. And the heating scheme will be the same for any type of heating. Radiators and coolant provide long-term cooling. This result is due to the choice of radiators with large capacity and wide pipe diameter. A large volume of hot water can be obtained by combining a single-circuit design and a heating column. For houses with a large number of sq. m. the operation of the boiler is not of fundamental importance, and the heating schemes of the boilers will be similar.
Connection features
Double-circuit boiler should not be designed in combination with a natural circulation system- after stopping the heating of the coolant, the movement will quickly stop. The reheating process takes a long time, and the heat in the radiator is distributed unevenly. However, most models are equipped with circulation pumps.
Classic version boiler piping with two-pipe circuit looks like that. Hot water rises into a supply pipe that spans the house above. Then the coolant passes through the connected risers with heating devices, which do not completely open the riser. Radiators are equipped with a jumper and a choke, necessary for heat regulation. Needed shut-off valve on the second line of eyeliner. The air vent is mounted at the top of the circuit expansion tank.
By bottom connection system, the coolant returns back. The advantage of the scheme is that it can work in natural circulation mode. The accelerator of the collector will be the pipe through which the coolant moves to the upper filling.
Typical connection errors
Safety valves
They are not used when the heating system is open. Valve purpose - protect the boiler from damage in case of a sharp increase in pressure. Usually the valve is forgotten or a model or safety group with different characteristics is installed.
During the valve response, part of the water flows out of the system, which ensures pressure release and protection. You should not insert the drain tube into the sewer, since the reason for the decrease in pressure will not be clear. You can get by with a funnel. By the way, there is no need to throw the septic tank into the coolant.
Air vent. The part must be installed immediately after installing the boiler to avoid “airing”. Often they simply forget to open it. This is also typical for wall options with factory function. By the way, the circulation pump is also ventilated.
The air vent must stand strictly vertically upward. When it starts to leak, there is a shut-off valve in front of it, so replacing it with a new one will take a couple of minutes.
Circulation pump. The pump will operate properly only when the axis is in a horizontal position, and this position will significantly extend the “life” of the bearings.
It is advisable to protect the mechanism from dirt and debris from the outside. Strainers sold separately
Radiators. Disadvantages when connecting a panel radiator to the coolant. The radiator design involves connecting the supply pipe to the internal vent, located almost in the center, and to the outermost one - in the return pipe. The reverse connection order will reduce the heat transfer of the radiator by half. By the way, decorative screens disrupt heat exchange by 10-20%.
Proper installation and correct power calculations will help create maximum comfort for living in country house in any season.
To provide efficient heating dwellings, it is necessary to perform the piping of a gas boiler for heating a private house as competently as possible. It consists of several elements arranged in a certain sequence.
Types of connection
Autonomous heating can be implemented using:
- Wall-mounted single-circuit boiler with electronic ignition, providing forced circulation in the radiator system.
- Non-volatile wall or any floor equipment.
- A non-volatile boiler installed in an open circuit with natural circulation.
- Heating circuit modifications for heated floors. This is characterized by a low coolant temperature.
- A single-circuit boiler connected to a hot water supply system. We are talking about a wiring diagram for a gas heating boiler with a boiler
- Double-circuit boiler providing heating and hot water supply. In this way, a double-circuit gas boiler with a boiler is connected, which is quite popular.
- When the DHW circuit has water recirculation. Thanks to the constant movement of water in the circuit, heated towel rails connected to the hot water supply are kept hot. It also ensures high-speed hot water supply to the mixers.
If a hot water supply of considerable length does not have water recirculation, it will require prolonged draining before heating. In addition to the known inconveniences, this also entails financial losses. The same applies to dead-end DHW distribution without recirculation. In this case, heating of heated towel rails connected to the wiring occurs exclusively during water intake.
Harness complete set
The harness includes the following elements:
- Diaphragm expansion tank. Designed to compensate for surges in coolant volume during heating. This need arises in closed heating systems. Inside the container there is an elastic membrane that divides it in half. One half contains air or nitrogen (in this case, the walls of the tank do not corrode). When the volume of coolant increases, this provokes compression of the gas: as a result, the total pressure in the system remains almost at the same level. The standard volume of the expansion tank is 10% of the amount of coolant. For a rough calculation, a ratio of 15 l/kilowatt of heating boiler power is usually used.
- Safety valve. Resets excess coolant when the pressure in the circuit rises to dangerous levels. As a result, pipes and radiators are protected from rupture. A drainage pipe is provided to drain water into the sewer. If this valve operates regularly, this indicates insufficient capacity of the expansion tank.
- Air vent. If air pockets occur, they are removed automatically. We are talking about air accumulations formed in the system as a result of draining the coolant. Because of them, hydraulic noise arises and additional obstacles to normal circulation in the mode of low hydraulic pressure.
- Pressure gauge. Controls the operating pressure in the circuit. It is sometimes replaced with a thermomanometer, which additionally records the temperature. The scale of the device must have a marking of up to 4 atmospheres.
- Open expansion tank. Replaces the expansion tank, air vent and safety valve in an open circuit. In this case, the system does not encounter problems overpressure. A tap is used to connect a tank communicating with the atmosphere to the DHW system: this ensures recharge of the circuit.
- Indirect heating boiler. Inside this heat-insulated container with a heat exchanger, hot water is prepared. Heat is supplied by means of coolant flowing through the heat exchanger from the heating system. This element is included in the piping diagram of a gas single-circuit heating boiler; the connection of an indirect heating boiler must be carried out by specialists.
- Circulation pump. Thanks to him, it is possible forced circulation coolant through the heating circuit. When selecting a suitable pump, pay attention to the level of pressure it creates and productivity. Power consumption indicator in modern models adjustable within 50-200 W. Thanks to this, the speed of movement of the coolant can be changed depending on the situation.
- Hydroarrow. Several heating circuits can be connected to this container with pipes. Its task is to combine the supply and return pipes. As a result, it becomes possible to bring together systems with different temperatures and coolant speeds, smoothing out their mutual influence.
- Coarse filter. Inside the settling tank with a filter mesh, large particles in the water are retained. Most often we are talking about sand and scale. As a result, the thin heat exchanger tubes in the gas boiler are prevented from clogging.
- Two- and three-pass thermostatic mixers. Thanks to them, it becomes possible to create coolant recirculation, the temperature of which is an order of magnitude lower than that in the main circuit. A thermal head is used to control the mixer shutter. The valve changes its position in response to the temperature of the sensing element.
Pipes
Using pipes, the gas boiler is connected to the heating system, and the coolant is distributed in the required directions.
If the design of an autonomous heating system is done correctly, its parameters are absolutely stable and controllable:
- Temperature inside convection circuits (equipped with radiators or convectors). Should not be more than + 75-80 degrees. Heating of heated floors does not exceed + 25-35 degrees.
- Pressure. Permissible limits: 1 -2.5 kgf/cm2.
If the circulation pump fails, the thermostat will almost instantly stop the combustion process. This will protect the coolant from overheating and boiling. For this reason, the switching of the boiler and heating distribution is often carried out using polymer and metal-polymer pipes, which allows you to save on the purchase of expensive metal products.
- To implement sequential wiring of radiators and boiler switching, they most often use metal-plastic pipes with press fittings. Another common option is polypropylene products with aluminum reinforcement.
- When installing threaded fittings for metal-plastic, special care must be taken: if the O-rings move even slightly, this will lead to a leak. As a rule, such a nuisance should be expected after several heating-cooling cycles.
- Unreinforced polypropylene (or glass fiber reinforced) has a very high elongation coefficient. An increase in temperature by 50 degrees provokes an elongation of each meter of pipe by approximately 6.5 and 3.1 mm, respectively. This option is also unsuitable.
- To organize radial wiring or underfloor heating, metal-plastic pipes with press fittings, pipes made of cross-linked polyethylene or thermally modified polyethylene are also used.
Varieties of heating schemes for a private house
In the very simple version There is no boiler wiring diagram at all. In the vast majority of cases, the factory equipment of boilers with electronic ignition consists of the following elements: a pump, an expansion tank, an automatic vent and a valve (with a pressure setting of 2.5 kgf/cm2). The location of all piping units is the building: as a result, the complex is transformed into a mini-boiler room.
As additional elements, the system can be equipped with:
- Filter. Its installation location is the inlet pipe. As a result, the heat exchanger receives protection from contamination while increasing the hydraulic resistance of the circuit. This leads to a decrease in the speed of movement of the coolant, and the pump itself experiences additional load.
- Ball valves. They are installed at the inlet and outlet sections. This makes it possible to dismantle the heat exchanger or boiler while maintaining the heating circuit.
Floor-standing gas boilers with piezo ignition
Boilers with piezo ignition and floor-standing equipment do not belong to mini-boiler rooms: we are talking about heating devices that require external piping.
It includes:
- Pump. To select pump performance, use the formula Q = 0.86R/Dt (Q - productivity in m 3 / hour, R - thermal power boiler or a separate circuit, Dt is the temperature difference between flow and return). In order for a convection heating system with gas boilers to work normally, the temperature difference must be 20 degrees (+75-80 degrees on the supply pipeline, and +55-60 on the return pipeline). A boiler power of 36 kW assumes the following reasonable minimum pump performance - 0.86x36/20 = 1.548 m 3 /h.
- Membrane expansion tank.
- Safety valve.
- Automatic air vent.
- Pressure gauge.
The optimal location for the safety group is the boiler outlet: it is here that the temperature and pressure indicators reach their maximum values. The pump is placed in front of the boiler, in an area with the lowest coolant temperature (this allows you to significantly extend the service life of the impeller and rubber seals). The expansion tank can be mounted anywhere in the system: the main thing is that the distance to the pump impeller is no more than two diameters (if it is installed in front of the pump).
When installed after the pump, this distance is increased to eight diameters. This distance is necessary so that pressure surges that occur during pump operation do not reduce the life of the tank membrane. To prevent condensation from appearing, the heat exchanger is often equipped with an additional small circulation circuit. If the return pipe is cooled, it is possible to add hotter coolant inside it (it is taken from the supply pipe through a mixing unit).
Natural circulation
The gravity system is characterized by complete energy independence: its operation is ensured by atmospheric pressure. Instead of a bulky safety group in the piping of a single-circuit boiler, an expansion tank is sufficient. For bottling, it is advisable to install a vent in front of the boiler heat exchanger: this will make it possible to completely drain the water into the sewer or drainage well. Typically, such a need arises in the event of a long departure, or when the gas supply is cut off. As a result, the system is protected from defrosting.
The individual components of the system are located as follows:
- It is recommended to install the tank above all other elements.
- The bottling located immediately after the boiler is positioned in the vertical direction (a small angle is allowed). Thanks to the acceleration section, the water heated in the heat exchanger rises to the top filling point.
- It is important to maintain a constant slope when laying the bottling after the tank. As a result, the cooling water will return by gravity: in this case, air bubbles will be able to escape inside the expansion tank.
- The boiler must be lowered as low as possible. The best place for placing the heater - a pit, ground floor or basement. Due to the difference in height between the heat exchanger and heating devices, the proper level of hydraulic pressure is ensured, ensuring water circulation in the circuit.
Some features of arranging an inertial heating system:
- For the internal filling diameter, an indicator of 32 mm is selected. If plastic or metal-plastic pipes are used, then the outer diameter is 40 mm. Thanks to the large cross-section, compensation is achieved for the minimum hydraulic pressure due to which the coolant moves.
- The gravity system sometimes includes a pump: however, this does not mean that the circuit loses its energy independence. In this case, the pump is mounted not in the filling gap, but parallel to it. To connect individual taps, a ball-type check valve is used, which is characterized by very low hydraulic resistance. Also install ball valve. If the pump stops, the bypass is shut off, which preserves the functionality of the natural circulation circuit.
Warm floor
There are several options for connecting them.
Hydroarrow
This node includes both circuits:
- The first uses the movement of coolant between the hydraulic arrow and the boiler heat exchanger.
- In the second, one or more heating circuits with different heating levels are switched to it.
The operating principles are as follows:
- The vertical hydraulic arrow makes it possible to select coolant at different temperatures. The top section will be hot and the bottom section will be cold.
- When water is taken from the upper pair of taps, switching of convection heating is allowed. The lower pair is used in an intra-field circuit.
- The coolant temperature below the switching level of the return pipe of the circuit at the junction of the water gun and the boiler may drop noticeably.
Recycling
In a parallel position to the main contour radiator heating or a small circuit in the area from the boiler to the hydraulic switch, a low-temperature circuit is being installed. It contains a bypass and a three-way thermostatic valve. Thanks to the pump, water constantly circulates inside the underfloor heating pipes.
To select new portions of hot coolant from the supply pipe when the temperature inside the return pipe drops, a three-way mixer is used. It can be replaced with a simple thermostatic valve equipped with a remote capillary-type temperature sensor or an electric thermocouple. The sensor is installed in a niche on the return line of the heated floor. The valve is activated when the coolant temperature drops.
Radiator connection of serial type
This option is possible if a condensing gas boiler is used, because The operation of classical equipment is difficult at return temperatures below +55 degrees. The fact is that a cooled heat exchanger collects condensate on its surface. Gas combustion products contain, along with water and carbon dioxide, aggressive acids. In this case, there is a real threat of destruction of steel or copper heat exchangers.
Condensing boilers have a different operating principle. To collect combustion products, a special heat exchanger made of of stainless steel(economizer). As a result, additional heat transfer occurs and equipment efficiency increases. Because of this, the return pipe temperature level of +30-40 degrees is optimal. Heating system consists of two series-connected circuits - radiator and in-floor. The return pipe of the first is the supply pipe of the second.
Single-circuit boilers with DHW supply
To provide hot water supply, along with a safety group, pump and expansion tank, the piping of a single-circuit gas boiler must include an indirect heating boiler. A connection diagram for an indirect heating boiler with recirculation is possible. In this case, water is heated thanks to the coolant from the heating circuit. This leads to the appearance of two circulation circuits - a large one (through the heating system) and a small one (through the boiler). Each of them has shut-off valves, which allows you to turn them on separately. To break the supply bottling, a piping scheme is used for a single-circuit boiler with a boiler, immediately behind which a bypass with a tap is installed.
Creating a heating system involves connecting a boiler and heating devices (radiators, convectors and warm water floors). The system must also contain security devices. The procedure for connecting this entire facility is called “boiler piping”.
What is a harness and what is it made of?
The heating system has two main parts - the boiler and radiators or heated floors. What connects them and ensures safety is the harness. Depending on the type of installed boiler, different elements, therefore, they usually consider separately the piping of solid fuel units without automation and automated (usually gas) boilers. They have different operating algorithms, the main ones being the ability to heat the boiler heater in the active combustion phase to high temperatures and the presence/absence of automation. This imposes a number of restrictions and additional requirements that must be met when piping a boiler running on solid fuel.
An example of a boiler piping - first there is copper, then there are polymer pipes
What should be in the harness
To provide safe work The heating system of the boiler must contain a number of devices. Must be:
Some of these devices are already installed under the casing of a gas wall-mounted boiler. The wiring of such a unit is very simple. In order not to complicate the system with a large number of outlets, the pressure gauge, air vent and emergency valve are assembled into one group. There is a special housing with three outlets. The corresponding devices are screwed onto it.
This is what a security group looks like
Install a safety group on the supply pipeline immediately at the boiler outlet. They are placed so that it is easy to control the pressure and you can manually release the pressure if necessary.
What pipes to use
Today, metal pipes are rarely used in heating systems. They are increasingly being replaced with polypropylene or metal-plastic. Piping a gas boiler or any other automated boiler (pellet, liquid fuel, electric) is possible immediately with these types of pipes.
When connecting a solid fuel boiler, at least a meter of supply pipe cannot be made with a metal pipe and, best of all, a copper pipe. Then you can switch to metal-plastic or polypropylene. But this is not a guarantee that polypropylene will not collapse. Best to do additional protection from overheating (boiling) of the TT boiler.
Which polymer pipes are better? Polypropylene or metal-plastic? There is no clear answer. Polypropylene piping is good because of the reliability of the connections - properly welded pipes are a monolith. (). But as much as possible permissible temperature coolant in the system - no higher than 80-90°C (depending on the type of pipe). And then, prolonged exposure to high temperatures leads to rapid destruction of polypropylene - it becomes brittle. Therefore, piping the boiler with polypropylene is done only in low-temperature systems based on automated boilers.
If there is protection against overheating, the boiler piping can be made with polypropylene pipes
Metal-plastic has more high temperature operation - up to 95°C, which is sufficient for most systems. They can also be used to piping a solid fuel boiler, but only if there is one of the systems for protecting against overheating of the coolant (discussed below). But metal-plastic pipes have two significant drawbacks: narrowing at the connection point (fitting design) and the need to regularly check the connections, as they leak over time. So, lining the boiler with metal-plastic is done under the condition that water is used as a coolant. Antifreeze liquids are more fluid, so it is better not to use compression fittings in such systems - they will still leak. Even if you replace the gaskets with chemically resistant ones.
Gas boiler piping
Modern gas boilers They have good automation that controls all parameters of the equipment: gas pressure, the presence of a flame on the burner, the pressure level and temperature of the coolant in the heating system. There is even automation that can adjust work to weather data. In addition, wall-mounted gas boilers in most cases contain such necessary devices as:
The parameters of all these devices are indicated in the technical data of gas boilers. When choosing a model, you need to pay attention to them and choose a model not only by power, but also by the volume of the expansion tank and the maximum volume of coolant.
Wiring diagram for a wall-mounted gas boiler
In the simplest case, the boiler piping contains only shut-off valves at the entrance to the boiler - so that, if necessary, it is possible to renovation work. A dirt filter is also installed on the return pipeline coming from the heating system to remove possible contamination. That's all the harness.
An example of piping a wall-mounted gas boiler (double-circuit)
In the photo above there are corner Ball Valves, but this, as you understand, is not necessary - it is quite possible to install ordinary models, and turn the pipes closer to the wall using corners. Also note that there are taps on both sides of the sump tank - this is so that you can remove it and clean it without draining the system.
In the case of connecting a single-circuit wall-mounted gas boiler, everything is even simpler - only gas is supplied (gas workers connect), hot water is supplied to radiators or water warm floor and return from them.
Wiring diagrams for floor-standing gas boilers
Floor-standing models of gas heating boilers are also equipped with automatic equipment, but have neither a safety group, nor an expansion tank, nor circulation pump. All these devices have to be installed additionally. Because of this, the wiring diagram looks a little more complicated.
On two classical boiler piping schemes, an additional jumper is installed. This is the so-called “anti-condensation” loop. It is needed in large systems; if the return water temperature is too low, it can cause condensation. To eliminate this phenomenon, this jumper is installed. With its help, hot water from the supply is mixed into the return pipe, raising the temperature above the dew point (usually 40°C). There are two main ways to implement it:
- with installation of a circulation pump with an external temperature sensor in the jumper (and the photo is at the top right);
- using a three-way valve (pictured below left).
In a scheme with a circulation pump on a jumper (condensation pump), it is made with a pipe of a smaller diameter than the mains. The sensor is attached to the return pipe. When the temperature drops below the set value, the pump power circuit is turned on and hot water is added. When the temperature rises above the threshold, the pump turns off. The second pump is the heating system itself; it works all the time while the boiler is running.
In the second scheme with a three-way valve, it opens the addition of hot water when the temperature drops (set on the valve). In this case, the pump is located in the return pipeline.
Solid fuel boiler piping
Any owner of a TT boiler knows that during the active combustion phase a lot of heat is released. Over time, experience comes - when and how exactly to close the damper, for what period of time, etc. But if you get a little distracted, the water in the system will overheat and may even boil. To prevent this phenomenon, the boiler piping without automation must contain several devices that prevent the system from boiling. Only in this case can wiring around the house be done with polymer pipes. Otherwise, sooner or later, the overheated coolant will soften the material, the pipes will burst with all the ensuing consequences. Therefore, the piping of a solid fuel boiler except traditional elements- safety group, expansion tank and circulation pump - contains a significant number of additional devices and usually requires quite a lot of money.
The cyclical nature of the operation of solid fuel boilers leads not only to boiling of the system, but also to the fact that the house is either very hot (when the fuel is actively burning), or cold - when everything has burned out. To eliminate these phenomena, there is a solution: install an indirect heating boiler or a heat accumulator. Both are containers with water, they just perform different functions and, accordingly, are connected in different ways.
Connection with an indirect heating boiler
With this design, there is no sudden increase in temperature during active combustion, which is usual for a solid fuel boiler. This is because the volume of the tank is added, so there is practically no overheating of the water. Then, when the fuel has burned out and the house begins to cool down in a conventional system, the heat stored in the heating phase continues to be consumed in the system with TA. In this way, the temperature background is equalized and the time between fires increases.
This type of connection to a solid fuel boiler is more reliable and wiring from the heating element can be done polypropylene pipes, but it is necessary to make a circuit from the boiler to the tank metal pipes. In this case, you can use steel ones, but copper ones are still better.
TT boiler piping with overheating valve
The third way to protect a solid fuel boiler from overheating is to install automatic device overheat protection. This special valve with temperature sensor. The principle of operation is simple: when a certain temperature is exceeded (usually 95-97°C), the valve opens the inlet of cold water from the water supply, and releases excess superheated water into the sewer. This is how, for example, REGULUS DBV 1-02, Regulus BVTS 14480 works.
Protection of a solid fuel boiler from overheating using the REGULUS DBV valve
Although the valves are manufactured by the same company, they have different structures and installation patterns. So REGULUS DBV is installed at the boiler outlet and has a built-in temperature sensor (installation diagram - above). The overheating protection valve of the TT boiler Regulus BVTS 14480 has a remote sensor and can be mounted both at the inlet and outlet (installation diagram below). What's good about this option? The fact that it can work in systems with natural circulation - it does not need pressure to work.
Heating boiler piping with coolant boiling protection valve
Their estimated cost is 40-60 € - this is much less than the cost of installing a heat accumulator or an indirect heating boiler, but this method does not solve the problem of temperature fluctuations. These valves, by the way, can be used to increase the reliability of a circuit with an installed indirect valve and thereby eliminate the possibility of the system boiling.
What else is needed in the system
The boiler piping will be incomplete if it does not have a tap to drain and fill the system. And it is better if they are separate. The specific installation location depends on the structure of the system, but there are certain rules:
In some systems, the drain and fill of the system are made from one tap. This is possible if there is a pump that pumps and there is a pressure gauge by which you can control the pressure created. If there is a separate tap for filling the system at a high point, it can be filled by gravity.
