Two boilers in one heating system: in what cases this is necessary, the requirements and connection schemes

For both comfort and energy savings, you must make sure your home has effective insulation and heating. The boiler, which generates steam or heats water to provide warmth, is an essential part of a heating system. A single boiler, however, might not always be enough to meet the heating requirements of a larger or more complicated property. This is where the idea of using two boilers in a single heating system makes sense.

However, why would someone think about installing two boilers as opposed to just one? There are multiple situations in which this method works well. First off, a single boiler may find it difficult to provide heat evenly throughout a larger house or building with several floors, rooms, or zones. Two boilers allow for better control over the heating load and uniform warmth throughout the property.

Furthermore, having two boilers enables greater customization and output optimization for properties with different heating needs, such as those with both radiant floor heating and conventional radiator systems. A heating zone or system can be assigned to each boiler, thereby optimizing comfort and efficiency.

Let’s now explore the needs and factors to take into account when combining two boilers into a heating system. First and foremost, it’s imperative to make sure the boilers and the current infrastructure are compatible. To work well together in the system, the boilers should have comparable specs, including fuel type, capacity, and efficiency ratings.

In addition, boiler sizing must be done correctly to prevent underperformance or inefficiencies. An expert heating technician can evaluate the property’s heating load and suggest the right boiler size to efficiently meet the demand. Boilers that are either too big or too small can waste energy and cause discomfort.

There are different configurations for connection schemes for a dual-boiler setup based on the needs and preferences of the homeowner or property manager. Common configurations include series piping, in which one boiler serves as the primary heat source and the other as a backup or supplemental unit, or parallel piping, in which each boiler operates independently and provides heat to distinct zones.

In conclusion, properties with different heating requirements or larger spaces in need of more effective heat distribution may find that combining two boilers into one heating system is a workable solution. Homes can optimize their heating systems for increased comfort and energy savings by knowing the specifications, compatibility factors, and connection schemes.

In what cases two boilers are installed

When the current apparatus is unable to handle the necessary heat load, it is decided that a second apparatus needs to be installed. You can do away with the insufficient equipment power with an additional boiler.

Diagram for the installation of two boilers

Other signs that two boilers should be connected to the heating system at the same time include:

• errors when determining the thermal power of boiler plants;
• expansion of the area of the house to be heating;
• increasing the capabilities of the heating source;
• limited volume of basic fuel.

Requirements for furnace

The boiler room requirements are applied based on the type of energy used when installing two units of the same type: electric, gas, coal, or firewood.

When selecting boilers that use various fuel types, the building must adhere to the regulations for both heating, and the maximum parameter is eventually approved. Usually, solid fuel devices are meant by it.

Conditions for devices using solid fuel:

• The minimum area of the floor is prescribed respectively by the total thermal return of the boilers (from 7.5 to 15 m²);
• a heater with a capacity of more than 30 kW is located in the center of the boiler room to ensure free air circulation;
• walls, partitions, floor, ceiling of the room are finished with fire -resistant materials using waterproofing;
• The boiler is mounted on the base of non -combustible materials;
• For heater with a capacity of less than 30 kW, increased requirements for the fire resistance of the floor are not presented, it can be covered with sheet steel;
• Solid fuel should be stored in a special room, the location of the daily reserve is allowed, but at a distance from the boiler more than 1 m;
• The furnace should have windows and door, providing a three -fold exceeding the norm of air circulation from the calculation of the volume.

An illustration of the ground floor boiler room’s location

The following specifications are given to gas-powered heating units:

• Boilers with a total capacity of up to 30 kW can be located in a separate non -resident room with a door and windows that provide three times air circulation;
• with a total power of boiler units over 30 kW, it is necessary to release a separate room with an area of at least 7.5 m² and with a ceiling height of 2.5 m;
• If the gas apparatus is installed in the kitchen with a gas plate, the area of the room is accepted at least 15 m².

Connection schemes

It is a very responsible step to strap two different types of boilers together in one scheme (solid fuel and gas). In addition to decreasing heating efficiency, any error could result in a crisis.

It is preferable to invite project organization specialists to calculate the connection scheme. They will pick up a few heaters with parallel or consistent strapping and a choice of manual or automated control mechanisms.

Automatic control

From a hydraulics perspective, the automatic control scheme is essentially the same as the manual approach. The two check valves that are installed are the only modifications.

They are positioned to stop coolant from escaping through a boiler that has been momentarily disconnected. A hydraulic shot is installed to solve the issue. On the return that is pointed in the direction of one another are finding valves.

Two automatic boiler controls

Installing a thermostat that shuts off the pump for forced coolant movement is also required for automatic systems. The idle circulation of water through the disconnected device is useless when solid fuel is burned in the furnace because it adds to the resistance of the second boiler.

Manual control

This option only requires a shut-off and regulating reinforcement to maintain the balance of two boilers’ work. The operator operates all boiler switching by opening and closing two valves on the return. The four valves (two on the supply and two on the return) must be closed in order to entirely halt the flow of heated water.

Two boilers connected via manual control

Two expansion tanks must be installed in manual control schemes in order to compensate for the thermal expansion of the water during the cold boiler’s gradual heating process. Two units’ simultaneous loads on one tank is too much for it to handle.

Methods of inclusion

Two techniques exist for strapping a pair of boilers together:

• consistent;
• parallel.

Sequential strapping connects the boilers in an alternating manner; extra nodes and lines do not need to be installed or deviced. The coolant is warmed by the first device moving in that direction, and the water is heated to the proper temperature by the second.

This is a low-power heater-only option that is rarely used. Since it is impossible to disassemble one boiler for repair without also shutting off the other, it is regarded as illogical. If even one of the two units malfunctions, the plan is useless. In addition to a bypass line, additional reinforcement is employed to modernize and boost efficiency.

Two points of connection for the coolant flows on the return and direct supply are outfitted with parallel strapping. Boilers operate separately from one another. Installing an automatic control unit and hydraulic shotus is feasible in this situation.

Binding schemes

It is relatively easy to bind two boilers of the same type. Integrate devices with different capacities that use different energy sources into the system.

Plans utilizing these pairs are employed:

• gas and solid fuel;
• electricity and gas;
• electricity and solid fuel.

Gas and solid fuel

This binding option is regarded as technically complex; in order to use it, a separate vent system must be installed, and the boiler room’s location must adhere to fire safety regulations.

The gas boiler strapping scheme and repair

The guidelines for the safe operation of gas and electric boilers must be considered. As such, the project’s development ought to be assigned to the appropriate organization.

The implementation of a multi-circuit system allows the network to operate at its ideal temperature. Heat units with two separate contours are chosen for its creation. Since it is nearly impossible to regulate the coolant’s heating in solid fuel boilers, only open systems with the installation of an expansion tank as a requirement are permitted.

It is forbidden to use a closed heat supply system with a gas and solid fuel unit, as this constitutes a flagrant breach of fire safety regulations.

Gas and electric

Efficient, simple to administer, and easy to put into practice. A considerable thermal effect can be obtained by combining an electric and gas boiler. Such a scheme is more cost-effective than a single gas boiler, subject to optimizing operating modes.

Connecting a gas boilerand an electric boiler

Given that the leading in the pair forms thermal energy at a lower cost, it is assigned a gas apparatus. If electricity is priced differently, it makes sense to include only nighttime use.

Pay attention to the binding circuit when determining the boilers’ necessary thermal power. The electric apparatus needs to have a maximum power for operation at night or with a peak increase in heat consumption, while the gas apparatus should have a higher power.

Regulatory documents do not impose any limitations on the cooperative operation of these devices. However, the project involving the furnace needs approval from the gas service and energy supervision.

Solid fuel and electric boiler

Combining solid fuel and electric boilers is regarded as another efficient way to supply heat. This pair’s host is a solid fuel device that runs for about eight hours on a single fuel portion. It’s more than sufficient to heat the house.

The electric boiler is turned on once all of the fuel has burned and the coolant has reached 60 degrees Celsius. He keeps the temperature where the user has set it. A hot water accumulating tank is installed to improve energy efficiency. It is heated at night by an electric unit at a lower cost.

Connecting a solid fuel boilerand an electric boiler

A solid fuel boiler cannot be adjusted because of the inertia of the combustion process. Until the fuel is completely burned, he provides all of the heat produced in the firebox at nominal performance.

In this instance, the battery tank will power the secondary circuit that controls the heating mode. By combining hot coolant from the supply pipeline with cold water from a return, it can be adjusted using a three-way crane.

In some circumstances, installing two boilers in a single heating system can be a workable solution. Having two boilers can increase efficiency and dependability, whether it’s for load balancing, backup, or continuous heating in larger properties.

Making sure the boilers are compatible and the right size is important when choosing a dual boiler setup. To satisfy the property’s heating needs, both boilers should have the proper size. They should also work with the same control systems, fuel types, and efficiency ratings.

Connection plans are essential to the efficient operation of two boilers. For the building’s heat to be distributed evenly, proper zoning and plumbing must be put in place. Furthermore, both boilers should be able to operate and be optimized with ease thanks to the integration of control systems.

When installing and using dual boilers, it’s critical to follow manufacturer instructions and safety regulations. To maintain maximum performance and safety, this also entails appropriate ventilation, gas line sizing, and routine maintenance.

The choice to install two boilers in a single heating system should ultimately be made in light of the particular demands and specifications of the property. Even though the initial cost might be higher, over time the benefits of greater flexibility, efficiency, and reliability may make the investment worthwhile.

In the realm of heating and insulating your home, the integration of two boilers into one heating system can offer practical solutions in certain scenarios. Understanding when this setup is necessary, along with the requirements and connection schemes involved, is crucial for homeowners seeking efficient heating solutions. This approach is often employed in larger properties or buildings with diverse heating needs, where a single boiler may not suffice to meet demand adequately. Whether it"s accommodating different fuel sources, optimizing energy usage, or ensuring backup heating, the decision to implement a dual-boiler system requires careful consideration of factors like space, budget, and energy efficiency goals. By exploring various connection schemes and adhering to installation requirements, homeowners can effectively harness the benefits of this approach to enhance comfort and energy efficiency in their homes.

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