The development of new heating systems is ongoing. Modernization of the boiler, improving the parameters of radiators and pipes. However, along with new methods of maintaining a comfortable temperature in a living room, alternative methods are being developed. One of them is water heaters for home heating: flow-through, electric. At first glance, they are intended only to provide hot water supply. But is it? To understand this issue, it is necessary to analyze the technical and operational qualities of these schemes.
The principle of operation of a water heater for heating
Usually the boiler is used only for hot water supply. Structurally, it is a container, inside which heating heating elements are located. When filled, they heat the liquid to the required level. Then, through the outlet pipe, it enters the plumbing fixtures - mixers in the kitchen, in the bathroom. But in addition to this, you can make an additional circuit for heating the air in the rooms.
Before using the water heater for heating, the following conditions must be met:
- Provide liquid circulation in the pipes. If the container is constantly filled with running water, the heating agent heating rate will be minimal. Make a closed loop with circulation;
- Installation of the necessary heating elements - an expansion tank, a pump and valves;
- Provide for the possibility of replenishing the coolant from the water supply system.
But how to make heating from a water heater if it is not structurally designed for this? The specificity of the design and practical implementation of this task lies in the simultaneous use of the same water for DHW heating of the room. Therefore, first of all, it is necessary to install a pump of a certain power, which would ensure uniform heating by the water heater by the constant movement of liquid in the pipes. Then a filtration system should be made. Before entering the circuit, the water must be purified, since a large amount of impurities is characteristic of the flow-through, which negatively affects the condition of pipes and heating devices.
Before purchasing an electric water heater, you need to find out if it is suitable for heating. First of all, this concerns the availability of convenient control with the ability to quickly regulate the temperature level in the tank.
Is it worth installing water heaters from the heating system if there are electric boilers specially designed for this? Consider the characteristics of both systems.
Water heater or electric boiler?
The idea to use instantaneous water heaters for heating arose even when the first electric boilers appeared on the market. But most often, electric boilers are installed, which are designed specifically for heating. You can find out the relevance of installing instantaneous water heaters from the heating system after a comparative analysis of these devices with boilers.
An important indicator is the efficiency of the system - the ratio of the heat energy received to the consumed one. In this regard, electric boilers are much more efficient - their figure reaches 90%.At the same time, most electric instantaneous water heaters for heating have an efficiency not exceeding 70%. This is due to the specifics of the structures and the method of increasing the temperature of the coolant. Next, you should take into account certain performance characteristics.
The use of an instantaneous water heater is only possible for closed systems with forced circulation. This is due to the specifics of the device.
The method of heating water with a water heater
Modern electric water heaters for heating work on the same principle as boilers. A large sealed container is filled with water, which is heated using electric heating elements. In this case, heat loss occurs through the body.
In boilers, the coolant increases the temperature when passing through a heat exchanger with a built-in heating element. Since the volume of this chamber is relatively small, heating occurs quickly. At the same time, heat losses are minimal. It should also be noted that in most cases the design already has a circulation pump, an expansion tank and a convenient control system. In addition to the latter, electric water heaters for heating of the VEO type do not have these elements.
Heating inertness
The rate of temperature rise of water in pipes for electric boilers is quite high. The average heating time from 25 degrees to 60 is 15-20 minutes, depending on the volume of the system. In this regard, heating with a water heater is significantly inferior to the traditional one. In order for the volume of water in a boiler with a capacity of 150 liters to reach the desired temperature, it is necessary to wait about an hour. The main criteria affecting this indicator are the power of heating elements, the volume of the tank and the entire system as a whole.
However, when the electric boiler stops working, the water in the pipes cools down quickly. At the same time, in the water heater system, a large volume of hot liquid is in the tank and it will take several circulation cycles to cool it down. Those. in the event of an unexpected power outage, the coolant in the boiler system will still be hot for some time.
Summarizing these factors, you can determine the basic conditions for using an electric water heater for heating:
- The area to be heated must be relatively small. This is due to the ratio of 1 kW of thermal energy per 10 square meters;
- Good quality running water to preserve all heating elements;
- To fill the tank, it is necessary to create the same pressure as in the water supply system - 4 atm. This applies only to those cases when a conventional boiler is installed that is not intended for heating from a water heater. In specialized models, the value of the minimum pressure is much lower - from 1.5 atm.
You can use an electric water heater to heat a house with a small area of up to 80 sq. First of all, this applies to country buildings.
The second way to use an instantaneous water heater for heating is to equip a floor heating system. But even in this case, it is necessary to carefully read the diagram for connecting the device to the pipeline.
Indirect heating boiler
An acceptable alternative to the above-described method of heating rooms with a boiler is indirect heating tanks. By the principle of operation, they are similar to the classic ones, but with one exception - a serpentine tube is located inside, which is connected to the heating system.
But how can such a water heater be used for heating? First, it should be remembered that it is only an additional source of heating the coolant. The main boiler is any type. For efficient operation of the indirect heating boiler, it is recommended to install it in front of the return pipe inlet to the boiler. Heat from the hot water supply will be transferred to the coolant in the coil. Thus, you can make the optimal temperature regime of the system.
They differ from electric water heaters for heating, type BEO, in low efficiency as the main source of heat generation. But this way you can reduce the current costs of the energy carrier. When choosing an indirect heating boiler, it is recommended to pay attention to these parameters.
- The volume of the container. The area of contact of hot water with the coil depends on it. The larger it is, the more the coolant will heat up. The optimal volume should be 150 liters or more;
- Power of heating elements. Directly affects the rate of water heating. On average, for every 50 liters of volume, a power of 2 kW is required;
- Thermal insulation of the case. To minimize heat loss, it is better to choose models with a double wall, inside which there is a heater.
However, when organizing heating with a water heater of this type, the high cost should be taken into account.
For example, the popular Vaillant uniSTOR VIH R model with a volume of 200 liters will cost almost 20 thousand rubles. But this would be a better option than using a conventional water heater for heating.
Instantaneous water heater
An interesting solution for small areas are instantaneous electric water heaters for heating. Unlike boilers, they are capable of heating a small volume of water. The average performance of a relatively powerful 2 kW model will be 12 lit / min at a coolant temperature of 60 degrees.
Such structures are most often installed in summer cottages with non-permanent residence. Since heating can be made from a water heater, it is often used for its intended purpose - providing hot water. In this case, the system of pipelines for heating the coolant and DHW is common. The advantages of installing an instantaneous water heater as a heating device are:
- Small size. It can be placed almost anywhere in the kitchen or bathroom;
- The minimum indicator of inertness - the time for raising the temperature of the water in the pipes is short;
- Convenient adjustment of temperature conditions, as well as the presence of a heating element shutdown system in the absence of water in the pipes;
- A large selection of models that differ in both power and cost.
The main disadvantage of an instantaneous water heater for heating systems is the high consumption of electricity. Its constant use is impractical, as an exception, it is installed as an emergency way to maintain the temperature of the water in the pipes.
Self-production of a water heater for heating is not recommended. This is related to ensuring the safety of people living in the house.
Installation and selection of a heat carrier for a water heater
Before making heating from a water heater, it is necessary to calculate the optimal power. In this case, it is impossible to be guided by the nominal power of the installation. The main indicator is the time for heating the water to the desired temperature regime. In some models, it is limited to 20-30 minutes, but for most it is more than an hour.
When using a conventional electric water heater to heat your home, the following tips are recommended.
- The installation of the unit should be carried out in a warm and dry room. In this way, heat losses can be minimized;
- The wiring must be designed for the maximum load of the water heater from the home heating system;
- It is recommended to use plain distilled water as a heat carrier. Compared to antifreeze, it has a better heat capacity;
- It is best to purchase models with a closed heating element. This will prevent limescale build-up on the heating elements.
According to most experts, the best choice is electric type water heaters for heating, type VEO. It is important to choose the right model of a certain power. In this case, it is necessary to take into account the parameters of the main heating boiler.In total, they should form an optimal air heating system in the house.
The video material shows an example of self-installation of a conventional boiler as the main heating device.
