Currently, there are many ways to organize alternative heating. Most of them are characterized by low efficiency and are used only as an auxiliary system. However, there is a truly effective method of heat supply from alternative sources of heat of the earth. How to make geothermal home heating with your own hands: the principle of operation, pumps, reviews will help solve this issue.
The principle of geothermal heating
Depending on the composition of the soil, a natural temperature increase of + 3 ° C for every 100 m occurs. Geothermal heating in Europe, which has been used for more than a dozen years, is based on this phenomenon. But how to use this effect in practice?
The principle of operation of geothermal heating at home is to transfer thermal energy using several types of coolant. This requires several circuits, each of which performs its function:
- Outer. Pipelines are in an environment in which the temperature is from + 7 ° C to + 10 ° C. This energy is transferred to the coolant entering the next circuit.
- Heat exchange. The main element is a heat pump. The refrigerant circulates in it, in which, with increasing pressure, the temperature rises. Heated from the coolant of the external circuit, it enters the compressor. As a result of this, the temperature rises from + 7 ° C to + 65 ° C. To repeat the cycle, the liquid through the throttle enters the evaporator. This is the basic principle of geothermal heating.
- Inner contour. In it, with the help of a heat exchanger, heat energy is transferred from the refrigerant to the coolant in the main heating system of the house.
In order to properly do geothermal heating with your own hands, you must first select the primary circuit and the corresponding heat pump.
Geothermal heating can be combined with traditional types of heat supply - with a gas boiler, electric or solid fuel. Thus, it is possible to reduce the running costs of the coolant.
Types of geothermal heat supply at home
Before doing geothermal heating of a country house with your own hands, a number of preliminary measures should be taken. First of all, find the optimal way to arrange the primary circuit pipes.
The main condition is the temperature of the environment where the lines will be located. It should not be below + 7 ° C. In practice, for this, installation of pipelines in the ground is performed. In some cases, the main medium may be a reservoir or river. However, reviews of geothermal heating of this type of house often indicate low efficiency in the winter.
For the correct organization of alternative heat supply, the following steps must be performed:
- Calculate optimal power. If the geothermal heating of a private house will be the main one, its rated power should provide air heating throughout the building.
- To analyze the composition of the soil and the depth of freezing. The choice of the layout of the pipes of the primary circuit depends on this.
- Determine the location of the heat pump. To minimize heat loss, do-it-yourself geothermal heating systems are equipped in a separate room - a basement or a farm building. It is important that the temperature in it is not lower than + 14 ° C.
Failure to follow these simple rules can cause the system to malfunction. Often, reviews of owners of geothermal heating indicate the importance of initial analysis and the selection of the right equipment.
To ensure the smooth operation of the system, it is necessary to install an autonomous power source - a generator.
With horizontal placement
The least time-consuming method of installing the primary circuit pipes is horizontal. They are located at a depth of 0.5 to 3 m. To reduce the area of the trunk lines are located in turns. But at the same time, the distance to each should be at least 20 cm.
Before making geothermal heating, an initial analysis of the state of the soil is carried out. First, its heat transfer is determined. It can range from 20 to W / m². Based on this, the total length of the primary circuit is calculated.
In addition, you should perform the following actions:
- Checking the level of soil freezing. The depth of the pipe should be below this indicator;
- Ground water. For their natural removal during the period of large floods, a sand layer is poured onto the bottom of the pit;
- Pipeline material selection. It must be sufficiently flexible and mechanically reliable. For geothermal heating in Europe, cross-linked polyethylene pipes are most often used.
If the important question is how much the geothermal heating system costs, then a horizontal arrangement will help significantly reduce the current installation costs of the system. When installing several primary circuits, installation of the input and output collectors is necessary.
With vertical piping
Given the basic principles of geothermal heating at home during design, it is necessary to achieve maximum heating of the coolant from the ground. This can only be done with vertical lines.
To organize the geothermal heating of a country house with a vertical type of DIY, it is necessary to make wells with a depth of 30 to 100 m. The primary circuit pipelines are placed in them.
Such a scheme is more time-consuming than vertical, but has several advantages:
- Large depths of highways. In this case, the heat transfer of the environment increases by 25-30% - up to 70 W / m²;
- Small area for installation;
- Virtually no dependence on soil freezing.
In addition to this method, the basic principles of geothermal heating for hot water supply in the summer are often used. To do this, the primary circuit is placed in the water - a lake or river.
Before drilling wells, it is necessary to do a soil analysis and determine the optimal depth. The composition of the soil will directly affect the complexity of the process.
DIY geothermal heating installation
In practice, making this type of heat supply is a difficult task. A feature of the design and installation of do-it-yourself geothermal heating is the presence of a heat pump - the main unit of the system.
The design of this device includes an internal circuit with refrigerant, a compressor, a choke and an evaporator. To control the work, an electronic unit is necessarily provided. What should I look for when choosing a geothermal heat pump for heating?
- Device type. In heat supply, soil-water models are used. In addition to them, there are "water-water" and "air-water";
- Rated thermal power. It directly depends on the calculated parameters. It should be borne in mind that almost all models have a value of this characteristic up to 18 kW;
- Power consumption. This is the amount of electrical energy needed to operate the compressor, pump and electronic control unit. Directly depends on the rated power of the device;
- Heating system parameters - temperature and optimal pressure. For all geothermal do-it-yourself heating systems, the latter indicator usually does not exceed 3 bar;
- Cost. At present, the arrangement of geothermal heating of a private house is the most expensive. And most of the costs are the purchase of a heat pump. Therefore, special attention should be paid to the correct choice of this component of the system.
In addition to the geothermal heat pump for heating - it is necessary to choose the right pipes for the external circuit. They must meet certain requirements. In particular, to have a minimum indicator of heat transfer resistance. Ideally, steel lines should be used for this. However, their operation in this environment is associated with multiple problems. Therefore, they often make geothermal heating from polymer flexible pipelines.
After analyzing the reviews of geothermal heating at home, the following positive qualities of polymer pipes for this type of heat supply can be distinguished:
- Sufficient flexibility. This is important when arranging horizontal geothermal heating of a country house on its own.
- Easy installation and matching of individual circuits. For this, mechanical couplings are used.
- The ability to quickly replace the damaged area in case of emergency.
Also, do not forget about the cost. Given that the heat pump is the basis of the principle of geothermal heat supply, costs should be reduced in order to obtain the optimal model of this device.
For the full functioning of the system, it is recommended to use a special coolant composition in the primary circuit, which has a freezing temperature below 0 ° C.
Calculation of the cost of geothermal heating
For the consumer, one of the determining factors of heat supply is its price and maintenance costs. Given the wide experience of the European application of geothermal heating, you should first calculate the optimal budget.
For the independent creation of geothermal heating, it is not recommended to make a heat pump with your own hands. This is due to the complexity of the design and the obligatory technical calculations of its parameters. The best option is to purchase a ready-made geothermal heat pump.
The market presents models of many European manufacturers. There is a rating that will help determine the best option:
- HELIOTHERM;
- NEURA;
- OCHSNER;
- IDM
All models of these companies are not only of good quality, but also of high price. Therefore, before planning the geothermal heat supply of a private house, it is recommended to analyze the offers on the market.
| Model | power, kWt | Cost, rub. |
| Henk 120 | 9 | 230000 |
| Acwell BWH-12 | 12,4 | 366000 |
| Daikin ALTHERMA | 6 | 520000 |
| ESDWW-25C | 25 | 415800 |
In addition to these costs, the cost of other components should be taken into account - pipes, connecting elements and wiring of internal heating of the house. Significant savings can be achieved by installing a geothermal heating system yourself. However, when choosing a vertical installation scheme for the primary circuit, you can not do without the use of special equipment. On average, the cost of "turnkey" geothermal heating currently ranges from 700 thousand to 1.2 million rubles. It all depends on the planned capacity and budget.
Before buying a pump, be sure to read the reviews of the owners of geothermal heating. This will help you find out the actual performance of the equipment.
Reviews on geothermal heat supply
How can you make an objective opinion about this type of heating? One way is to familiarize yourself with reviews of the geothermal heat supply at home. This must be done very carefully. Some system owners do not quite understand the principle of geothermal heating. Therefore, there are negative reviews about its functioning:
- Long considered the relevance of installing a heat pump. The system is expensive, but given the electric heating of the house, it has proven to be a very productive tool for saving costs. Using only geothermal heating is irrational - the water heats up for too long. Therefore, we use it as an auxiliary system;
- The installation of a heat pump with pipes took almost two weeks. As it turned out, it is impossible to build on the site of laying highways. And they occupy a significant area of the yard. Now we are thinking about reworking - we will drill wells and re-mount the external circuit;
- We were assured that the heat pump is able to completely heat our rather big house - 230 m². But in winter, the water in the pipes barely heats up to + 50 ° C. Therefore, you have to periodically turn on a spare electric boiler.
Is it worth it to equip geothermal heating, given the complexity of installation and the high cost of equipment? This should be a balanced decision, supported by calculations and a complete analysis of the entire system. Only on the basis of these data can we determine the relevance of the installation of geothermal heating.
A real review of the work of geothermal heating can be found in the video material:
