Combined heating system - the choice and price of a mixed system
Different implementations
Easy system control
Integration into any interior
Comfortable temperature all year round
A combined heating system for a private house is implemented using several types of equipment. This approach is the most rational in the case when the main source of heat is not enough for house heating.
The cost of installing a heating system depends on many factors:
- selected heat source (electric, gas, solid fuel boiler or heat pump) and its manufacturer;
- the required area of underfloor heating or the presence of warm walls;
- number of heating devices, such as radiators, fan coil units and in-floor convectors:
- residential heating area, etc.
It is impossible to determine the exact cost of the heating system. Therefore, Alter Air specialists will be able to make a competent project, select all heating devices, and, accordingly, make a commercial offer. Thereafter, the installers will be able to qualitatively install the heating system, adhering to the project.
Conditions for combined heating
To create a high-quality and efficient combined heating system for a private house, certain conditions must be observed:
- the design of the building in all respects must meet the criteria for an energy-efficient home (availability of high-quality double-glazed windows, heat-insulating materials for walls and roofs);
- installation of a ventilation system with heat recovery;
- hydraulic system for low-temperature mode, which requires 100% underfloor heating surface (water or electric).
Recommended equipment
Heat source combination options
A combined home heating system is a combination of two or more heat sources to heat a home in winter.
The following combinations can be used for such a system:
- Heat pump and gas boiler.
- Heat pump and electric boiler.
- Solid fuel boiler and electric boiler.
- Solid fuel boiler and gas boiler.
Each type of heat source has its advantages and disadvantages. Therefore, we will consider options for a mixed heating system and equipment options.
Heat pump and gas/electric boiler
Heat pump and gas/electric boiler
First, before installing a heat pump, you must follow some rules:
- housing must meet the characteristics of an energy-efficient home. This implies insulation of walls, roofs, floors, as well as the presence of high-quality double-glazed windows;
- implementation of a ventilation system because without this system the load on electricity and heating system may be up to 25% per year;
- heating system with low-temperature mode:
- there must be a system of underfloor heating, the area of which must be 100% of the entire floor surface,
- installation of fan coil units – universal devices that are capable of performing the function of cooling and heating.
To achieve efficient operation of the heat pump for heating and cooling the house, it is necessary to install additional devices: fan coil units, radiators, in-floor convectors as well as underfloor heating system (the area must be 100% of the entire floor surface).
There are several types of additional heat sources:
- fan coil units - the main task of the devices is to supply warm or cooled air, depending on the time of year;
- radiators - units that have only one function - heating;
- in-floor convectors - devices that can work on heating the house during the cold period of time. When using equipment from Kampmann HK,
you will also be able to cool the building in the summer.
Underfloor heating is a low-temperature and indispensable element of the heating system. At the same time, using only a system of underfloor heating is an irrational solution, since to maintain an optimal microclimate, the temperature of the floor surface will exceed + 24-26 °C, which will create discomfort for the human foot. Therefore, to achieve the maximum level of comfort, it is advisable to install additional equipment.
It should be noted that when implementing a heating system using underfloor heating, radiators and convectors, in the summer period you will not be able to perform the function of cooling the house. Therefore, by replacing radiators and convectors with floor-mounted fan coil units, you will get a comfortable air temperature in summer and winter.
According to the method of placement, fan coil units are divided into several types:
- floor-mounted;
- wall-mounted;
- ducted;
- cassette.
Floor-standing fan coil units are considered the best option for installation in houses and apartments, since the installation of the device is carried out along the double-glazed window. This setting will help to avoid cold / heat gains in housing.
In addition, Alter Air experts recommend installing a ducted air conditioning system, with which you can achieve the maximum level of comfort for a person, and it is also more suitable for this type of premises.
The heat pump is capable of performing not only cooling / heating functions, but also hot water supply, so you can use hot water all year round. In this case, it is necessary to consider the water flow rate, with which you can calculate the maximum amount of water consumption. Since the water limit must be calculated at the time of maximum water consumption, the correct solution would be to calculate the morning and evening time.
In addition, it should be noted that for country houses up to 200 m² it is recommended to use an air-to-water heat pump, and for an area from 200m² - a ground source heat pump.
A combined heating system with a heat pump and electric boiler means connecting the heat pump as the main source, and the electric boiler as an additional one. In the case when the air temperature is low outside and the heat pump cannot physically cope with the heating of the building, an electric boiler starts working. An important role in choosing a heat pump belongs to thermotechnical calculation. With the help of thermotechnical calculation, you can find out the range of operating temperatures up to which the air-to-water heat pump can independently cope with heating the house.
In this case, based on the data obtained, if the capacity of the heat pump is not enough, a decision will be made to additionally install an electric or gas boiler.
In the case of choosing a gas boiler, Alter Air experts recommend using a condensing type gas boiler, as it is more efficient (COP (coefficient of performance) can tend to be higher than 100% due to the use of additional energy - condensate), in comparison with an atmospheric / turbocharged boiler.
Gas and solid fuel boiler
Gas and solid fuel boiler
A combined heating system with a gas and solid fuel boiler involves the usage of a solid fuel boiler as the main element of the system, and a gas boiler as additional equipment.
This combination is beneficial in the following cases:
- the design of the building does not meet the characteristics of an energy-efficient home;
- heating a house with your own raw materials, since buying fuel with a high density and a moisture content of no more than 30% is an expensive solution;
- limited supply of kW electricity to the house.
For the high-quality functioning of the heating system, it is necessary to follow some rules:
1. There must be a controller with which you can set the required temperature of the heat carrier, at which the solid fuel boiler will switch to gas.
For example, the residents of the house set the heat carrier temperature to +60 °C. As a result, when the temperature of the coolant is below the set one, the controller will provide an impulse to the gas boiler and the unit will start working up to the set temperature.
2. Transportation of hot water should be carried out by pumping groups, directly to radiators, floor convectors and underfloor heating.
Pumping groups are indispensable elements of the heating system, since they provide a higher temperature supply to radiators and convectors, and for underfloor heating (low temperature equipment) - a much lower temperature to prevent overheating of the floor surface.
3. There must be a heat accumulator.
The process of burning wood is irreversible. Even without loading the solid fuel boiler with raw materials and stopping the air supply, the wood will continue to burn. Therefore, for a solid fuel boiler, it is necessary to install a buffer tank so that it can give the minimum amount of kW to a special barrel.
The calculation of the buffer capacity shows that for 1 kW, it is necessary to provide 40-45 liters of water.
4. There must be small and large heating circuits.
When the solid fuel boiler is turned on, the device should only work by itself up to a temperature of +60 °C. Thereafter, the boiler will be able to supply hot water for the heating system. If the temperature of the heat exchanger is below +60 °C, the condensation process will take place. As a result, the heat exchanger will become wet and eventually begin to deteriorate. To prevent this problem, a two-way valve must be installed.
The two-way valve is a device that controls the temperature of the solid fuel boiler, which must not fall below +60 °C. If this condition is not met, condensation will appear inside the device. In addition, condensation is accompanied by the release of a few kilojoules, since the heat will turn into steam, which will be thrown out into the street. As a conclusion, the solid fuel boiler will turn into low-efficiency equipment.
In order for the combined heating system to be effective, it is necessary to have high-quality thermal insulation of the house and install a condensing type gas boiler.
When using a gas boiler of this type, it is necessary to use radiators that are designed for a heat carrier temperature of + 55 °C at the inlet to the device and + 45 °C at the outlet.
Electric and solid fuel boiler
Electric and solid fuel boiler
Combined heating with electric and solid fuel boilers in one system consists of using a solid fuel boiler as the main source of heat, and an electric boiler as an additional one.
The principle of operation of this mixed heating system in a private house is no different from a hybrid heating system of a solid fuel boiler and gas boiler.
At the same time, it should be noted that an electric boiler + solid fuel boiler, in comparison with solid fuel boiler + gas boiler, require more resources for the quality functioning of the system, since electricity has a higher price in relation to gas. Accordingly, combined heating with an electric boiler and a solid fuel boiler in one system is considered an irrational solution.
Hybrid heating system with solar collectors
Hybrid heating system with solar collectors
It is irrational to use a solar collector for heating a house because, due to low solar activity in winter, the device can not provide the house with the necessary amount of heat. Therefore, the solar collector is used only for hot water supply.
Special conditions of cooperation
We are happy to jointly conduct projects with organizations and self-employed specialists, recommend you to our clients and help with the outsourced engineering part. Additionally, we invite you to attend seminars of the "Engineering in Design" series, where we show by examples how to correctly implement engineering systems in the interiors of end customers.
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Heating devices combination
Combined home heating involves the use of various heat distributors:
- convectors;
- radiators;
- underfloor heating and warm walls.
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Convectors
For combined heating, only in-floor convectors are used.
The principle of operation of the convector is natural and forced convection. This implies a constant circulation of warm and cold air masses in the room, as the warm air cools, becomes heavier and goes down.
The selection of the convector depends on the thermotechnical calculation. Since the wrong size of the device will lead to poor-quality heating of the room.
An important part when choosing a convector is its installation method. The installation of the unit takes place only under the window, since it is there that the largest amount of cold passes in winter.
Underfloor heating and warm walls + additional heat sources
Underfloor heating is the main element in the implementation of the heating system. Since underfloor heating is a low-temperature element of the heating system, it is necessary to comply with special requirements for the supply temperature of the heat carrier. The temperature of the floor surface should be in the range of + 24-26 °C, since an increase in floor temperature can lead to a decrease in human comfort.
When the floor temperature rises, the following problems may occur:
- high temperature of the floor surface, which will create discomfort for the foot;
- with constant temperature fluctuations, the floor will not be able to cool down quickly because the concrete tends to heat up slowly and cool down for a long time.
Based on this, to prevent these problems and create an optimal microclimate at any time of the year, it is necessary to install additional heat sources, such as:
- fan coil units - devices that can provide a comfortable and uniform supply of warm or cooled air, regardless of the season;
- radiators - used only for space heating;
- in-floor convectors - devices that provide heat, but with the installation of Kampmann HK – you can also get housing cooling in the summer.
For the efficient operation of the heating system, a prerequisite is the availability of pumping groups that can carry out the supply of a higher temperature to convectors and radiators, and lower for a warm floor to prevent overheating of the floor surface.
Warm walls can also be used in the implementation of the heating system. It should be noted that the installation of warm walls should be carried out in the range of 1.5 meters from the floor level. When installing the system, it is forbidden to hang any equipment and place furniture where the pipelines for the warm wall system are laid.
Equipment for mixed heating system
Components of the system
The combined heating system includes various heat sources and heating devices that are used to implement the system.
Heat pump
Heat pump is considered the most efficient and cost-effective equipment that can perform three functions: space heating / cooling and hot water heating at any time of the year. Therefore, a heat pump with underfloor heating and additional devices such as fan coil units, radiators, in-floor convectors will provide residents with an optimal microclimate in a house or apartment, and will also reduce the cost of maintaining a house.
The heat pump has several advantages:
- energy-efficient equipment due to high heat conversion efficiency. Accordingly, when buying 1 kW of electricity, an air source heat pump can deliver 3 kW of heat, and a ground source heat pump – up to 6 kW of heat energy. Therefore, by installing a heat pump, you will significantly reduce the cost of maintaining a house;
- an advantageous device, as it can work not only for heating housing in the winter, but also for cooling it in the summer, as well as for heating water for hot water supply;
- high environmental friendliness, since the device does not emit combustion products into the environment;
- minimum costs for heating, cooling the house, as well as hot water when using special tariffs for electricity.
Our engineers recommend paying attention to the following brands of heat pumps:
- Vaillant or LG air-to-water heat pump;
- Mitsubishi air-to-air heat pump;
- Vaillant ground source heat pump.
Electric boiler
An electric boiler is a device designed to heat a home thanks to electricity.
Advantages of an electric boiler:
- cost-effective device when using special tariffs for electricity;
- no release of harmful and dangerous combustion products into the environment, so the device is considered environmentally friendly;
- the availability of weather-dependent and time modulation, which will provide an opportunity to regulate the temperature in the room, taking into account the indicator of the sensor, which is located on the street. In addition, you can program the temperature of the air supply over time. This automation will provide residents with a rational use of electricity.
Despite the obvious advantages of the device, the electric boiler has numerous disadvantages:
- low efficiency. An electric boiler with 1 kW is capable of delivering 0.9 kW of thermal energy, since heat is lost when converting electrical energy into thermal energy. But, if we compare an air heat pump and ground source heat pump with an electric boiler, then an electric boiler has a lower efficiency;
- possible power outages and fluctuating mains voltage may cause the device to shut down;
- availability of high input power consumption for the house. This must be considered before installing the electric boiler, as each dwelling has a limited kW supply.
Alter Air experts recommend using the following brands of electric boilers, which are in high demand among customers:
Solid fuel boiler
Solid fuel boiler – a device designed for heating houses using the process of burning solid fuels. Various types of solid raw materials can be used as fuel: firewood, coal, pellets, and briquettes.
Today, the installation of a solid fuel boiler is not a rational solution, since for the high-quality operation of the boiler, many fuel requirements must be met, and raw materials are considered quite expensive.
Fuel requirements are as follows:
- raw materials for solid fuel boilers must have a high density. In the case when firewood has low kilocalories, this will provoke poor heat transfer – which will have a bad effect on the efficiency of the boiler and on your finances, since you will have to spend many times more raw materials to ensure the optimum air temperature in the rooms.
- humidity of raw materials should not exceed 30%. Therefore, raw materials must be stored in a dedicated area to prevent moisture from accumulating.
Gas boiler
A gas boiler is a device that creates thermal energy by burning gaseous fuel. Before installing a gas boiler, it is necessary to consider whether there is a gas supply to the house.
There are several types of gas boilers:
- a turbocharged boiler is a device with a closed combustion chamber, the gas discharge of which occurs through the turbine to the street. It should be noted that the turbocharged boiler is not popular among buyers, since the device does not have a sufficiently high efficiency. Therefore, when a gas is burned, a certain amount of heat is lost.
- atmospheric boiler is an open-type equipment, for which installation in a special boiler room is a prerequisite. The atmospheric boiler also does not have great demand among consumers. Its disadvantage is that the device, having a sufficiently large heat exchanger power, will not be able to provide the desired modulation.
- condensing boiler is a device that has higher cost-efficiency and capacity compared to other types of boilers. The condensing boiler has a unique function because the combustion products are not emitted into the atmosphere, but are stored and used in the system in the form of water vapor. Based on this, the condensing type boiler has a high efficiency, which is more than 100%, as well as good technical characteristics.
Therefore, the purchase of a gas condensing boiler is the best option, in comparison with atmospheric and turbocharged boilers.
Since manufacturers of well-known brands Vaillant and Protherm produce not only high-quality electric boilers, but also gas boilers, Alter Air engineers recommend products from these brands.
Solar collectors
A solar collector is an alternative source of energy, the principle of which is to heat the coolant using the thermal energy of the sun. The equipment is used for hot water supply, household and other needs.
Our projects
TROX double slot inline diffuser
Double-slot diffusers from the TROX brand are designed for high-quality air distribution throughout the room. They combine visual aesthetics and high technical potential. Air currents are given in different directions, evenly scattering and avoiding any drafts. Outwardly, only laconic lines on the ceiling remain visible.
Duct air conditioner Daikin FDXM 35F
A low-pressure internal duct unit Daikin FDXM 35F is installed in the ceiling space of the bathroom - it works to cool the bedroom. It is accessed through hatches. The capacity of the air conditioner is enough to service rooms up to 35 m2, which is optimal for a given room. The lowering of the ceiling in a technical room was 300 mm.
Indirect heating boiler Drazice
Vertical indirect heating boiler Drazice OKSE 200 l is designed to provide apartment residents with hot water. The inner surface of the tank is covered with high-quality enamel without nickel, which ensures a long operation of the water heater, and there is also an anti-corrosion coating. The temperature inside can be kept between 7 and 77 ℃. The water heating indicator always shows the current temperature on the front of the tank. There is a fast heating function. This is an excellent solution for an apartment, allowing you not to depend on seasonal blackouts and other inconveniences.
Electric boiler Vaillant Ecoblock
Electric boiler Vaillant Ecoblock An electric boiler Vaillant Ecoblock with a capacity of 6 kW and efficiency of up to 99% works for heating and hot water supply of the entire apartment. It has a wide range of temperature settings for both heating and hot water supply. There are frost protection and 2-level overheating protection. Equipped with eBus data transmission technology. With the help of a capillary thermostat, residents can smoothly regulate the heating temperature in the range from 25 to 85 ℃
Expansion tank Zilmet
The Zilmet expansion tank is designed to compensate extra pressure in the heating system. Works in conjunction with the Vaillant electric boiler above. The special inner lining of the tank prevents the growth of any bacteria, that is, the water does not acquire a metallic taste, does not stagnate or change its properties.
Refiner Ecowater - water softening and filtration system
A modern system for filtering and softening water: cleans water from all kinds of impurities and odors, neutralizes iron, making it soft, pleasant and safe for household appliances, water pipes and human use. The purified water is also suitable for drinking directly from the tap. The refiner does not require changing the carbon filters, and is controlled via WiFi - maximum automation and comfort!
Duct air conditioner Daikin FBA 60
Кондиционеры Daikin FBA 60 – мощные сплит-системы канального типа, предназначенные для скрытого монтажа практически любого помещения.
HVU with heat recovery JABLOTRON FUTURA L
Highly efficient air handling unit for general ventilation in houses and apartments. Reuses the heat and moisture that are present in the room. Has a "native" VAV-system (variable air supply).
Ventilation unit Jablotron Futura L
The Jablotron Futura L ventilation unit with heat and moisture recovery ensures high-quality air exchange at the apartment, and also reduces the load on the heating system in the cold season. Thanks to the Alfa wall controller and the MyJablotron mobile app it is easy to operate the unit.
Airflex flexible insulated duct
Flexible air ducts Airflex have a high degree of plasticity, which allows air to be supplied even to hard-to-reach areas. Moreover, they are covered with a layer of thermal insulation, which prevents heat loss and absorbs noise characteristics during the operation of the ventilation unit.
Galvanized steel duct with thermal insulation
Thanks to galvanized steel, the duct does not suffer corrosion and other damaging influences. Thus, the long-term operation of the climate systems is ensured.
Duct air conditioner Daikin FBA50A9 (indoor unit)
The Daikin duct air conditioner provides efficient room cooling. The FBA series has a rather thin body, which makes it easy to place in a ceiling space. The self-diagnosis function ensures a safe operation of the device and indicates problems if any occur.
System implementation steps
01
Concept Development
This is the fundamental and first stage, in which all the wishes of the client, the characteristics of the object and the budget are discussed. This information helps you to get a general idea of what your climate system will look like.
02
System Design
The design of engineering systems in the house includes accurate calculations, the development of drawings and diagrams, planning and location of the heating system, as well as tasks for installers and builders.
03
Equipment selection
Alter Air will provide several equipment options that will suit the buyer in the best way, with full consideration of the corresponding quality and price.
04
System installation
Installation of a boiler room and a heat distribution system is not only a matter of comfort, but also of safety. The final start-up of the heating system takes place in the presence of the chief engineer and the client, in order to make sure that all components are functioning correctly.
05
Commissioning
Commissioning is an important stage before the first start of the equipment. It is necessary to check the installation and all settings of the systems in full accordance with the project.
06
System service maintenance
In a heating system, both the heat source and the heat distribution equipment need regular maintenance to ensure long and efficient operation. We do not recommend neglecting this stage to avoid unpleasant, and sometimes even dangerous consequences.
Video reviews
FAQ
Which combined heating system is best for a private house?
The best solution for a private house is the installation of a heat pump.
Heat pump is a highly efficient equipment that can work for heating, cooling and hot water supply. Therefore, a heat pump paired with underfloor heating and additional heat sources is able to provide an optimal indoor climate at any time of the year.
In the case when the outside temperatures are low and the heat pump is not able to fully provide the housing with the necessary heat, it is rational to install a hybrid heating of a heat pump with an electric boiler.
Which combination of heat sources is more cost-effective in Ukraine?
The profitability of combined heating of a private house depends on the availability of resources on the site.
For example, if you have a low-power input to the house, but there are gas pipelines on the site, then installing a gas condensing boiler would be a rational solution. In the case when you do not have a gas supply to the house, but at the same time you have a sufficient amount of kW, it is advantageous to install a heat pump.
Which combined heating system is easier to maintain?
To date, a heat pump is considered the most profitable and easiest device to maintain. The reason for their popularity is the reduction of home maintenance cost. An air heat pump can convert 1 kW of electricity into 3 kW of heat, and a ground source pump – up to 6 kW of heat energy.
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Валерий Игоревич
Все понятно и доступно, спасибо за помощь. Поставили котел, а он совсем еле работает. Уже расстроились, что выкинули на ветер немалые деньги. Но оказывается все проблемы решаемы. Оставили вам заявочку на консультацию.