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 supplying heat from alternative sources of earth heat. How to make geothermal heating at home with your own hands: the principle of operation, pumps, reviews will help solve this issue.
How geothermal heating works
Depending on the composition of the soil, there is a natural increase in temperature by + 3 ° C for every 100 m. It is on this phenomenon that geothermal heating in Europe is based, which has been used for more than a dozen years. But how can this effect be used in practice?
The principle of operation of geothermal heating at home is to transfer thermal energy using several types of heat carrier. This requires several circuits, each of which performs its own function:
- Outer... The pipelines are located in an environment with temperatures ranging 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. A refrigerant circulates in it, in which the temperature rises with increasing pressure. Heated from the coolant of the external circuit, it enters the compressor. As a result, the temperature rises from + 7 ° C to + 65 ° C. To repeat the cycle, the liquid enters the evaporator through the throttle. 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 make geothermal heating with your own hands, you must first select a primary circuit diagram and an appropriate heat pump.
Geothermal heating can be combined with traditional types of heat supply - with a gas boiler, electric or solid fuel. In this way, the running costs of the heating medium can be reduced.
Types of geothermal heating 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 best way to arrange the pipes of the primary circuit.
The main condition for this is the temperature of the environment where the lines will be located. It should not be lower than + 7 ° С. In practice, for this, pipelines are installed in the ground. In some cases, a body of water or a river can act as the main environment. However, reviews about geothermal heating of this type of house often indicate low efficiency in winter.
For the correct organization of alternative heat supply, you must perform the following steps:
- Calculate optimal power... If geothermal heating of a private house is to be used as the main one, its rated power should provide heating of air throughout the building.
- Analyze the composition of the soil and the depth of its 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 losses, geothermal heating systems are equipped with their own hands in a separate room - a basement or an outbuilding. It is important that the temperature in it is not lower than + 14 ° C.
Failure to follow these simple rules can lead to system malfunction. Often, reviews from owners of geothermal heating indicate the importance of initial analysis and selection of the right equipment.
To ensure uninterrupted operation of the system, it is necessary to install an autonomous power source - a generator.
Horizontal placement
The least time consuming method of installing the primary pipes is horizontal. They are located at a depth of 0.5 to 3 m. To reduce the area of the highway, they are arranged 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 be 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 pipes must be below this indicator;
- Ground water... For their natural removal during the period of large floods, a sand layer is poured into the bottom of the pit;
- The choice of material for the manufacture of pipelines... It must be flexible enough and mechanically reliable. For geothermal heating in Europe, XLPE pipes are most commonly used.
If the question of how much a geothermal heating system costs is important, then a horizontal arrangement will help to significantly reduce the current costs of installing the system. When installing multiple primary circuits, it is necessary to install the inlet and outlet manifolds.
With vertical pipelines
Considering the basic principles of geothermal heating of a house during design, it is necessary to achieve maximum heating of the coolant from the ground. This can only be done when installing vertical lines.
To organize geothermal heating of a country house with your own hands of a vertical type, it is necessary to make wells, with a depth of 30 to 100 m. Primary circuit pipelines are placed in them.
Such a scheme is more laborious than a vertical one, but it has a number of advantages:
- Great depth of the highways. In this case, the heat transfer of the environment increases by 25-30% - up to 70 W / m²;
- Small installation area;
- There is practically no dependence on soil freezing.
In addition to this method, the basic principles of geothermal heating are often used for hot water supply in the summer. For this, the primary circuit is placed in water - a lake or river.
Before drilling wells, it is necessary to analyze the soil and determine the optimal depth. The composition of the soil will directly affect the labor intensity of the process.
DIY geothermal heating installation
In practice, this type of heat supply is a difficult task. A feature of the design and installation of geothermal heating with your own hands is the presence of a heat pump - the main unit of the system.
The design of this device includes an internal refrigerant circuit, a compressor, a choke and an evaporator. To control the work, an electronic unit is necessarily provided. What to look for when choosing a ground source heat pump for heating?
- Device type... In heat supply, "soil-water" models are used. In addition to these, there are "water-water" and "air-water";
- Rated heat output... It directly depends on the design parameters.It should be borne in mind that almost all models have a value of this characteristic up to 18 kW;
- Power consumption... It is the sum of electrical energy required to operate the compressor, pump and electronic control unit. Directly depends on the rated power of the device;
- Heating system parameters - temperature regime and optimal pressure indicator. For all do-it-yourself geothermal heating systems, the latter indicator usually does not exceed 3 bar;
- The cost... Currently, the arrangement of geothermal heating of a private house is the most expensive. And most of the cost is 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 a ground source heat pump for heating, you should 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, geothermal heating will often be made from polymer flexible pipelines.
After analyzing the reviews about 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 your own.
- Ease of installation and docking of individual circuits. For this, mechanical couplings are used.
- Possibility of prompt replacement of the damaged area in the event of an emergency.
Also, don't forget about cost. Considering that the principle of operation of geothermal heat supply is based on a heat pump, costs should be reduced in order to acquire 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 point below 0 ° C.
Calculating the cost of geothermal heating
For the consumer, one of the determining factors of heat supply is its price and maintenance costs. Taking into account the wide experience of the European application of geothermal heating, the optimal budget should first be calculated.
To create geothermal heating yourself, it is not recommended to make a heat pump yourself. This is due to the complexity of the design and the mandatory technical calculations of its parameters. The best option is to purchase a ready-made geothermal heat pump.
There are models from many European manufacturers on the market. There is a rating of them, which will help determine the best option:
- HELIOTHERM;
- NEURA;
- OCHSNER;
- IDM.
All models of these companies are distinguished not only by good quality, but also by a high price. Therefore, before planning geothermal heating for a private house, it is recommended to analyze the proposals 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 for internal heating of the house. Significant savings can be achieved by self-installing a geothermal heating system. However, when choosing a vertical installation scheme for the primary circuit, you cannot 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 know the actual performance of your equipment.
Reviews about geothermal heat supply
How can you form an objective opinion about this type of heating? One of the ways is to read in detail the reviews about geothermal heating at home. This must be done very carefully. Some system owners do not fully understand how geothermal heating works. Therefore, there are negative reviews about its functioning:
- The relevance of installing a heat pump has been considered for a long time. The system is expensive, but with electric home heating, it has proven to be a very productive cost saving tool. It is irrational to use only geothermal heating - the water heats up for too long. Therefore, we use it as an auxiliary system;
- The installation of the heat pump with pipes took almost two weeks. As it turned out, it was impossible to build at the place where the highways were laid. And they occupy a significant area of the yard. Now we are thinking about reworking - we will drill wells and mount the outer contour in a new way;
- We were assured that the heat pump is capable of completely heating our rather big house - 230 m². But in winter, the water in the pipes barely heats up to + 50 ° C. Therefore, it is necessary to periodically turn on a spare electric boiler.
Is it worth equipping 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 the relevance of the installation of geothermal heating be determined.
A real review of the work of geothermal heating can be found in the video:
