Currently, ongoing development of new heating systems. Modernization of the boiler, improved parameters of radiators and pipes. However, along with new methods for maintaining a comfortable temperature in a living room, alternative methods are being developed. One of them is water heaters for heating a house: instantaneous, electrically. At first glance, they are intended only to provide hot water. 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 of which are located heating elements. When filling, they heat the liquid to the required level. Then, through the exhaust pipe, it enters the plumbing fixtures - faucets 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:
- Allow fluid to circulate in the pipes. If you constantly fill the tank with running water, the heating rate of the coolant will be minimal. Make a closed loop with circulation;
- Installation of the necessary elements of heating - expansion tank, pump and shutoff valves;
- To provide for the possibility of replenishing the coolant from the water supply system.
But how to make heating out of a water heater if it is not structurally designed for this? The specifics of the design and practical implementation of this task lies in the simultaneous use of the same water for domestic hot water heating. Therefore, first of all, it is necessary to install a pump of a certain power, which would ensure uniform heating by a water heater by the constant movement of liquid in the pipes. Then you should make a filtration system. Water must be purified before it enters the circuit, since a large amount of impurities that adversely affect the condition of pipes and heating appliances is characteristic of flowing water.
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 controls with the ability to quickly control the temperature level in the tank.
Is it worth it to install water heaters from the heating system, if there are specially designed electric boilers 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 they install electric boilers that are designed specifically for heating. The relevance of installing instantaneous water heaters from the heating system can be ascertained after a comparative analysis of these devices with boilers.
An important indicator is the efficiency of the system - the ratio of heat to energy consumed. In this regard, electric boilers are much more efficient - they have this figure reaches 90%. At the same time, most instantaneous electric water heaters for heating efficiency do not exceed 70%.This is due to the specific design and method of increasing the temperature of the coolant. Further it is necessary to consider certain operational qualities.
The use of instantaneous water heater is possible only 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, the heating of which occurs with the help of electric heating elements. This causes heat loss through the housing.
In boilers, the coolant increases the temperature when passing through a heat exchanger with an integrated heating element. Since the volume of this chamber is relatively small, heating occurs quickly. In this case, heat losses are minimal. It should also be noted that in the design in most cases there is already a circulation pump, an expansion tank and a convenient control system. In addition to the latter, electric water heaters for heating type VEO do not have these elements.
Inertness of heating
The rate of increase in water temperature 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 traditional. In order for the volume of water in the boiler with a capacity of 150 liters to reach the desired temperature value, you need to wait about an hour. The main criteria affecting this indicator are the power of the 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 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. Those. in the event of an unexpected 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 of the heated room should 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 - 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 minimum pressure value 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.m. First of all, this applies to country houses.
The second way to use the instantaneous water heater for heating is to equip the underfloor heating system. But even in this case, you must carefully read the wiring diagram of the device to the pipeline.
Indirect heating boiler
An acceptable alternative to the above-described method of heating rooms using a boiler is indirect heating tanks. By the principle of operation, they are similar to the classic ones, but with one exception - there is a serpentine tube inside that is connected to the heating system.
But how can you use a similar water heater for heating? Firstly, it should be remembered that it is only an additional source of heating of the coolant. The main one is a boiler of any type. For the efficient operation of the indirect heating boiler, it is recommended to install it before the return pipe enters the boiler. Heat from the domestic hot water will be transferred to the coolant in the coil. Thus, the temperature regime of the system can be optimized.
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 energy costs. When choosing an indirect heating boiler, it is recommended to pay attention to such parameters.
- Capacity volume. 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 from 150 liters or more;
- Power TENOV. Directly affects the heating rate of water. On average, for every 50 liters of volume, a power of 2 kW is needed;
- 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, a high cost should be considered.
For example, the popular model Vaillant uniSTOR VIH R with a volume of 200 liters will cost almost 20 thousand rubles. But this will be a better option than using a conventional water heater for heating.
Instantaneous water heater
An interesting solution for small areas are flow-through electric water heaters for heating. Unlike boilers, they are able to heat a small volume of water. The average productivity of a relatively powerful 2 kW model will be 12 lit / min at a coolant temperature of 60 degrees.
Such designs are most often installed in cottages, with inconsistent living. Since it is possible to make heating 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 heating medium and domestic hot water is common. The advantages of installing a instantaneous water heater as a heating device are:
- The small sizes. It can be placed almost anywhere in the kitchen or bathroom;
- The minimum inertia indicator - the time for raising the temperature of the water in the pipes is small;
- Convenient adjustment of temperature conditions, as well as necessarily the presence of a shutdown system for heating elements in the absence of water in the pipes;
- A large selection of models that differ in both power and cost.
The main disadvantage of a flowing water heater for heating systems is the high power consumption. 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-made water heater for heating is not recommended. This is due to 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 optimum power. In this case, one cannot be guided by the rated power of the installation. The main indicator is the time of heating the water to the desired temperature. 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, it is recommended that you use the following tips.
- Installation should be carried out in a warm and dry room. In this way, heat losses can be minimized;
- Wiring should be designed for the maximum load of the water heater from the heating system at home;
- It is recommended to use plain distilled water as a heat carrier. In comparison with antifreeze possesses the best heat capacity;
- It is best to purchase models with a closed heater. This will prevent the appearance of scale 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 must form the optimal air heating system in the house.
The video shows an example of self-installation of a conventional boiler as the main heating device.
