Features of indirect heating boiler connection, schemes and recommendations

Selecting the appropriate heating system is essential for maintaining a warm and comfortable home. An indirect heating boiler is a well-liked choice because of its dependability and efficiency. What is an indirect heating boiler, though, and how does it operate? The ins and outs of indirect heating boiler connections, along with numerous schemes and crucial advice, will be thoroughly examined in this article.

Let’s start by figuring out what makes an indirect heating boiler unique from other types of heating systems. In an indirect heating system, a heat exchanger is used instead of the boiler, which heats the water directly in a direct heating system. This indicates that heat is transferred to the water in your home’s heating system by means of the boiler heating a separate fluid, typically water or a unique antifreeze solution. In addition to improved energy efficiency, this indirect method also lowers the risk of corrosion in the primary heating circuit.

Let’s now examine the various connections for indirect heating boilers. The "primary/secondary" piping arrangement is one typical configuration. This system uses a primary loop to connect the boiler to the heat exchanger and a secondary loop to distribute water throughout your home’s zones. This arrangement guarantees uniform heating throughout the house and provides fine control over the temperature in each zone.

The "zone valve" configuration is another well-liked design that employs motorized valves to control the flow of heated water to various areas of the home. With its ability to independently control the temperature in each zone, this method is particularly helpful for homes with multiple heating zones. Zone valves can also reduce energy use by only heating the parts of the house that are occupied.

When it comes to connecting your indirect heating boiler, there are several key recommendations to keep in mind. First and foremost, proper sizing is essential to ensure your boiler can meet the heating demands of your home. Consult with a qualified HVAC technician to determine the appropriate size and capacity for your specific needs.

Furthermore, your indirect heating system’s effective operation depends on a quality installation. To make sure everything is set up correctly, make sure to adhere to the manufacturer’s instructions and seek the assistance of a qualified installer. In order to keep your system functioning properly and avoid any future problems, regular maintenance is also necessary.

In summary, indirect heating boilers provide a dependable and effective way to maintain a warm and cozy home. You can extend the life and performance of your heating system by being aware of the various connection schemes and adhering to important guidelines.

Feature	Description
Hydronic System	A method of heating that uses water circulated through pipes to transfer heat to different parts of the house.
Boiler Location	Placement of the boiler should be centralized for efficient heat distribution.
Piping Layout	The arrangement of pipes should be designed to minimize heat loss and ensure even distribution.
Thermostat Placement	Install thermostats in optimal locations to accurately control temperature.
Expansion Tank	Include an expansion tank to accommodate changes in water volume due to temperature fluctuations.

Design and principle of operation

The design and operation methods of BKN water heaters set them apart from other types of water heaters. Direct heating appliances obtain their heat energy straight from the boiler. The coolant flowing through the heating circuit or another system heats the water in the BKN.

The BKN heater’s walls are heated by coolant that passes through the heat exchanger. Heat is transferred from them to the water-filled tank. The boiler is referred to as "indirect heating" because it does not heat directly.

Both circuits receive simultaneous water supply from the tank. The heating system is linked to the first one. The second involves heating tap water and distributing it to the locations where it is used.

The heating system is linked to both circuits in parallel, and coolant travels from it to the boiler via the supply pipe. Pumping and mixing devices are installed in the pipeline to improve system efficiency and speed up circulation.

After entering the tank, cold water that has already heated up is given to the water users.

A brass or copper heat exchanger, or coil, serves as the primary heating component. Its surface area is sizable, and the heater is housed inside the primary tank. The BKN casing is covered with a heat-insulating "jacket" to slow down the rate at which heat escapes from the outside; some models come with a casing in addition.

Magnesium anode installed in the upper portion of the tank prevents corrosion on metal components. As a safeguard against the effects of elevated pressure, an integrated safety valve and thermostat are present. In the event that the device is delivered without a safety unit, one must be installed separately during the plumbing process.

Three systems are linked to the boiler at the same time:

1. Heating.
2. Cold water supply.
3. DHW.

Linking the engineering systems and BKN together

Understanding the ins and outs of indirect heating boiler connections is essential when configuring your home’s heating system. This article walks you through it all, from different schemes to professional recommendations. Whether your goal is to maximize efficiency or make sure your home stays cozy, knowing these subtleties can make a big difference. So let’s get started and clear up any confusion regarding indirect heating boiler connections so that you can maintain a warm house and low energy costs.

Rules of piping

When the boiler is installed concurrently with the heating unit, pumping apparatus, and other components needed to put together the DHW network, wiring and plumbing become less complicated. Installing the BKH in a system that has already been set up is slightly more challenging.

For the boiler to operate as efficiently as possible, the following guidelines must be followed:

• the installation point is selected at a minimum distance from the boiler;
• a flat surface should be created for the installation;
• to prevent damage from thermal expansion on the outlet pipe of hot water is placed hydroaccumulator, its volume is taken from 10% of the capacity of the boiler;
• The circuits are equipped with taps;
• check valves are installed to prevent the return flow of water;
• To improve water purity, mechanical filters are installed in the supply pipe;
• A pump or pump group must be installed.

Hinged BKN can only be installed on solid brick or concrete walls; it cannot be installed on wooden or plasterboard partitions. Dowels, anchors, or clips hold brackets and other fasteners in place.

Equitable positioning of the water heater and boiler

The boiler should be installed at least as high as the boiler next to it, regardless of whether it is wall or floor standing. Floor standing models can be installed up to one meter high on a stable stand or a concrete foundation.

Either a false wall hides the pipes behind the heater, or they are routed to the side of it. Corrugated hoses should not be used for connections as the water pressure will break them.

The piping has the following useful components:

• discharge and circulation pumps;
• mechanical filter
• reducer;
• check valve;
• membrane tank with safety valve;
• three-way mixer;
• two-way thermostat;
• flow heat exchanger (optional).

Choice of connection method

Prior to the KN boiler being installed in the DHW system, the connection option (priority or non-priority) must be selected. You can obtain a lot of water fast with the first method. The boiler coil receives all of the coolant that is pumped through the system. The flow of coolant to the heating batteries begins only after the water reaches the predetermined temperature, which is set by the thermorelle.

The water takes longer to heat up when there is a non-priority connection since only a portion of the coolant volume is directed toward the boiler tank. In this instance, the DHW cylinder is connected to a separate circuit. Turning off the heaters is not an option.

The priority scheme is thought to be more sophisticated since it can quickly heat the necessary amount of water without sacrificing heating quality. The house won’t get very cold if the heating appliances are turned off for one to one and a half hours, but there will still be enough water for everyone’s needs. Sufficient boiler capacity is the sole requirement for the priority scheme to be realized.

Connection options

The type of system and boiler type influence the decision to choose one piping scheme over another. The location of the boiler, pipes, and pump connection are taken into consideration when choosing the BKN’s placement point.

With three-way valve

The thermostat-controlled switch is replaced with the valve. The coolant from the heating circuit flows to the boiler when the water cools.

This piping technique uses shut-off valves and simultaneously turns on the boiler and the heating system. The BKN is positioned next to the boiler, and on the supply side is a circulation pump and a three-way valve.

Scheme works especially well when multiple heating sources are used.

Scheme for connections using a three-way valve

Priority is given to this option, which involves quickly heating the water in BKN while turning off the heat for 30 to 60 minutes. The valve opens and allows the coolant to return to the system when the temperature reaches the desired level.

With circulation pumps

When the boiler is not used frequently or when cold water is needed, the plan works well. Two pumps are installed, one on the heating pipe and the other on the supply pipe in front of the water heater.

Thermostatically linked, the pump only turns on when the temperature drops. Much faster heating occurs in the water when forced circulation is used.

Two-pump scheme

By installing traditional tees in the connections, the installation is completed without the need for a three-way valve.

With hydrostrip

The version featuring a hydrostrip works well with multi-circuit systems and boilers that have a minimum capacity of 200 liters.

Applying hydrostrelka strapping

A hydrodistributor called a hydrostrilka was installed to make the tapping scheme simpler. It is not required to install pumps on every branch of the system during installation. Since the water pressure in each circuit is the same, thermal shock is unlikely.

Scheme with recirculation of the coolant

When an appliance, like a towel rail, requires a constant supply of hot water, coolant must be continuously circulated. The dryer will function as a heater in addition to always moving coolant when it is connected to the system.

The steady supply of hot water is a benefit of this plan.

Plan utilizing recirculation

1. Increased fuel consumption for constant water heating.
2. Water mixing in the BKN. Hot water rises to the upper half of the cistern and from it is directed to the water consumption points. In the recirculation scheme, hot and incoming cold water are mixed, which results in a lower outlet temperature.

A BCN model with recirculation that comes with towel dryer spigots is available for purchase. However, purchasing a standard appliance and connecting the dryer to use tees is less expensive.

Scheme with an energy-independent boiler

The tank’s placement above the boiler and heating components is where this scheme differs. Here, wall-mounted boilers that are suspended up to one meter above the ground work better.

When it comes to water heating speed, wall-mounted models outperform floor installation models by a significant margin. Its temperature is much lower, roughly the same as the return heat carrier’s temperature, and its reserve is smaller.

Diagram showing how BKN is connected in a gravity system

Gravity is the foundation for the energy-independent boiler heating principle. Even when the power supply or pumps are turned off, the heat transfer medium continues to circulate.

Connection procedure

It is vital to choose the equipment after deciding on the best plan. You will also require distribution combs, ball valves, valves, check or three-way valves in addition to the main devices.

A link is established in this order:

1. Preparing the place of installation (wall, floor).
2. Arrangement of wiring, marking of cold/hot water connections with appropriate colors.
3. Assembly of tees and pressure valve. Connections are fixed with glue-sealant.
4. Assembling the hot and cold water taps.
5. Connection to the power grid, installation of automatics and temperature sensor.
6. Choice of operating mode.
7. Checking the connection.

This process is standard and works with the majority of boiler models.

Nuances of tapping into the piping

All types of pipes, including steel, metal-plastic, and PP pipes, can be used to connect the boiler to the heating system.

The coolant temperature and budget will determine which option is best. For instance, the temperature in solid fuel boilers is essentially unregulated; on occasion, it can reach 100 °C. The installation of steel pipes is advised as a result.

Cutting into the RR pipe system

PP pipes have a simple installation process. For the piping, all you need is a soldering iron and specialty scissors to cut the necessary sections to the desired length. Following the establishment of the tapping point, a section of the pipeline is removed, its length being equal to the tee’s length minus 10 mm in each direction.

Using a soldering iron, heat the fitting and pipe to the necessary temperature before connecting them. Any kind of twisting is prohibited since it may cause the connection’s tightness to be violated.

Boiler connection to the railroad pipeline

Connecting corners and sections of pipes of different lengths, they are brought to the boiler spigots. The section is completed by soldering a threaded socket, which connects the entire main line.

Cutting into the steel pipeline

It is possible to connect the BKN to the steel pipeline without welding by using a clamp and a specialized "vampire" type adapter that has a hole in its body.

After the tie-in area has been cleaned and prepared, a clamp with a heat-resistant gasket is placed on top, and the bolts are tightened. After turning off the water supply, the tapping area’s water residue is cleared out.

A drill is used to drill through the clamp’s hole in the pipe section, and then the valve is screwed on. After that, the BKN is tied using the chosen scheme.

Insertion into metal-plastic pipes

This variation, which joins the BKN to a two-circuit boiler, is known for its dependability and simplicity. The nodes are connected by crimp fittings, and bends and turns are easily achieved by simply bending the pipe to the necessary angle.

Using metal-plastic pipes for insertion

Before tying the boiler, a pipe with the necessary length and cross-section is cut out. Next, the length of the tee and the section of pipe that needs to be connected are taken into consideration when choosing the point of connection.

The hole is made with special scissors. After being taken out of the tee, the nuts are screwed onto the various pipe ends. For reaming, one uses a screwdriver or a specialized calibrator. The tee is inserted, the rings are slid, and a wrench is used to clamp the nuts.

It is acceptable to use pipe fittings in place of tees, but further pressure testing is necessary during installation.

Boilers with indirect heating provide a cost-effective and useful way to heat homes, especially in areas with severe winters. Indirect boilers efficiently use less energy by connecting to an external heat source, like a solar thermal system or a conventional boiler. This allows for consistent warmth.

The adaptability of an indirect boiler connection is one of its main benefits. Due to the variety of heating sources available, homeowners can customize their system to suit their unique requirements and tastes. The versatility of indirect heating systems guarantees peak performance all year long, regardless of whether they are connected to a heat pump, a gas or oil boiler, or a renewable energy source.

Good planning is crucial for the installation of indirect heating boilers. Homeowners can choose the best connection plan by consulting with a licensed heating engineer or contractor and taking into account various aspects like the size of the property, the heating infrastructure already in place, and their financial constraints. Furthermore, safe and legal installation is guaranteed by following local building codes and regulations.

The longevity and effectiveness of indirect heating systems depend on routine maintenance. Regular maintenance, upkeep, and servicing help to maximize efficiency and avert possible problems. To keep their heating systems operating efficiently, homeowners should schedule yearly maintenance appointments with trained technicians.

In summary, indirect heating boiler connections provide homeowners with an effective and adaptable way to maintain a warm and cozy living space. With proper knowledge of the different connection schemes and adherence to installation and maintenance best practices, homeowners can minimize energy expenses and environmental impact while still enjoying dependable heating performance.

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