A simple DIY heat pump. How to make a heat pump for home heating with your own hands: the principle of operation and assembly diagrams. Heat pump water-to-water from air conditioner compressor

Heat pump completely by yourself (photo story)
(moderators, if necessary, please correct, otherwise it was not possible to fill in the post correctly)

Good afternoon, forum users!

I will tell my story in which I tried to solve the problem of heating my house.

Background:

There was only a built house on 2.5 floors. Square:

1st floor 64 m2,
2nd floor 94 m2,
2.5 floor 55 m2,
garage 30 m2.

From the very beginning, a used gas-fired wood-fired boiler with a capacity of 40 kW was purchased. But as the installation time approached, I completely ceased to be pleased with the prospect of harvesting firewood, the eternal struggle with garbage, and by nature I am more of a dervish, I can easily not appear at home for a couple of days.

And then I leaned towards liquefied gas. Note that the pipe natural gas low pressure passes 1.5 km from the house. But our population density is low, and pulling a pipe for me alone + project + installation just plunges me into horror.

I also can’t put a barrel on several cubes on the site. I don't want to ruin the look. I decided to install a couple of cabinets with a battery of 80-liter propane tanks of 6 pieces each.

The gas operator assured that they themselves come, change themselves, you just call us. The inconvenience included only a headache once every three weeks, as well as the possibility of an unauthorized entry of a gas car into my future cobblestone-passenger parking lot, rolling and dragging cylinders along it. In general, the human factor. But the case solved the problem:

Idea heat pump:

I've had the idea of ​​a heat pump for a long time. But the stumbling block was single-phase electricity and an antediluvian meter for 20 amperes of maximum load. It is not yet possible to change the eclectic power supply to a three-phase one or add power in our area. But unexpectedly, they planned to change the meter to a new one, 40 amperes.

Having estimated, I decided that this would be enough for partial heating (I did not plan to use the 2.5th floor in winter), I undertook to probe the heat pump market. The prices requested in one company (single-phase HP for 12 kilowatts) made us think:

Thermia Diplomat TWS 12 k. h. 6797 euros
Thermia Duo 12 k.v. h. 5974 euros

It required at least 45 amps for starting current.
In addition, since it was planned to take heat removal from well water, there was no confidence in the debit of my well. In order not to risk such an amount, I decided to assemble the TN myself, since some skills were from life. He worked when he was a manager for the distribution of ventilation and air conditioning equipment.

Concept:

I decided to make a HP from two single-phase compressors of 24,000 BTU each (7 sq. H. Cold). Thus, a cascade with a total thermal power of 16-18 kilowatts was obtained with electricity consumption at COP3 of about 4-4.5 kilowatts / hour. The choice of two compressors was due to lower starting currents, since it was thought not to synchronize their starts. As well as the phased commissioning. So far, only the second floor has been inhabited and one compressor will suffice. Yes, and having experimented on one, then it will be bolder to complete the second section.

Refused to use plate heat exchangers. Firstly, for reasons of economy, I did not want to pay 389 euros apiece for Danfos. And secondly, to combine the heat exchanger with the capacity of the heat accumulator, that is, by increasing the inertia of the system, thereby killing two birds with one stone. And I didn’t want to do water treatment for delicate plate heat exchangers, thereby reducing efficiency. And my water is bad, with iron.

The first floor is already equipped with a heated floor piping with an approximate step of 15 cm.

The second floor has radiators (thank God, it was enough stinginess to put them with 1.5 thermal reserves earlier). Coolant intake from the well (12.5 m. Installed on the first layer of dolomite. +5.9 measured on 03.2008). Disposal of waste water into the general sewerage system (two-chamber sump + infiltration soil absorber). forced circulation in the heating circuits.

Here is the schematic:

1. Compressor (so far one).
2. Capacitor.
3. Evaporator.
4. Thermal expansion valve (TRV)

It was decided to abandon other safety devices (filter-drier, viewing window, pressure switch, receiver). But if anyone sees the point of using them, I will be glad to hear advice!

To calculate the system, I downloaded the CoolPack 1.46 calculation program from the Internet.

And a good program for the selection of Copeland compressors.

Compressor:

I managed to buy from an old friend of the refrigeration, a little used compressor from a 7 kilowatt split system of some kind of Korean air conditioner. I got it almost for nothing, and I didn’t lie, the oil turned out to be completely transparent inside, it worked for only a season and was dismantled due to a change in the concept of the premises by the customer.

The compressor turned out to have a capacity of 25,500 Btu, which is about 7.5 kW. in cold and about 9-9.5 in heat. What made me happy, I was in the Korean split solid compressor American firm Tecumset. Here is his data:

Those. characteristics.

Compressor on R22 freon, which means a slightly higher coefficient useful action. Boiling point -10c, condensation +55c.

Lapsus number 1: For old times' sake, I thought that household split systems, only compressors of scroll type (scroll) are installed. Mine turned out to be piston ... (It looks a little oval and the engine winding is hanging inside). Bad, but not fatal. To its minuses, a quarter less resource, a quarter lower efficiency, a quarter more noisy. But nothing, experience is the son of difficult mistakes.

Important: Freon R22 under the Montreal Protocol will be completely decommissioned by 2030. Since 2001, the commissioning of new installations has been prohibited (but I am not introducing a new one, but have modernized the old one). Since 2010, the use of R22 freon is only used. BUT at any time you can transfer the system from R22 to its replacement R422. And no more trouble.

I fixed the compressor on the wall with L-300mm brackets. If I later mount the second one, I lengthen the existing ones using the U-profile.

2. Capacitor:

I successfully purchased a stainless steel tank of about 120 liters from a welder friend.
(By the way, all welded manipulations with the tank were performed free of charge by a respected welder. But he asked to mention his modest role for history!)

It was decided to cut it into two parts, insert a coil from a copper pipe of a freon guide, and weld it back. At the same time, weld in several technical inch-threaded connections.

The formula for calculating the surface area of ​​a copper coil pipe:

M2 = kW/0.8 x ∆t

M2 is the area of ​​the coil pipe in square meters.
kW - Heat dissipation power of the system (with compressor) in kilowatts.
0.8 - coefficient of thermal conductivity of copper / water under the condition of counterflow of media.
∆t is the difference between the water temperature at the inlet and outlet of the system (see diagram). For me it is 35s-30s = +5 degrees Celsius.

So it turns out about 2 square meters coil heat exchange area. I slightly reduced it, since the temperature at the freon inlet is about + 82 ° C, this can save a little. But as I wrote earlier Santa Claus, not more than 25% of the size of the evaporator!

The simulated system in CoolPack showed a Cop of 2.44 on stock heat exchanger tube diameters. And Cop 2.99 with a diameter one step higher. And this is to my advantage, since in the future I expect to attach a second compressor to this branch. I decided to use a ½ inch (or 12.7 mm outer diameter) copper pipe, refrigeration. But, I think, you can use the usual plumbing, it’s not like that there and there will be a lot of dirt inside.

Lapsus number 2: I used a pipe with a wall of 0.8 mm. In fact, she turned out to be very gentle, a little crushed and she already hesitates. It is difficult to work, especially without special skills. Therefore, I recommend taking a 1mm or 1.2mm wall pipe. So the durability will be longer.

Important: The freon conductor of the coil enters the condenser from above, exits from below. So condensing liquid freon will accumulate at the bottom and leave without bubbles.

Thus, having taken 35 meters of the pipe, he turned it into a coil, winding it around a convenient cylindrical object (cylinder).

At the edges, I fixed the turns with two aluminum slats for strength and equal spacing of the loops.

The ends were brought out with the help of plumbing transitions to a copper tube for twisting. He slightly drills them from a diameter of 12 to 12.7 mm, and instead of a compression ring, after assembly, he wound flax on a sealant and clamped it with a lock nut.

3. Evaporator:

No evaporator required high temperature, and I chose a plastic container like a 127 liter barrel with a wide mouth.

Important: A 65 liter barrel would be ideal. But I was afraid, the ¾ pipe bends very badly, so I took a larger size. If anyone has other sizes or has a good pipe bender and work skills, then you can take a chance on this size. With a 127 liter drum, my HP increased the expected dimensions by 15 cm up, 5 cm deep and 10 cm wide.

I calculated and manufactured the evaporator according to the same principle as that of the condenser. It took 25 meters of pipe ¾ 'inch (19.2mm outer) with a wall of 1.2mm. As stiffening ribs, I used segments of the UD profile for the installation of gypsum plaster. Twisted with ordinary copper electrical wire without insulation.

Important: Flooded type evaporator. That is, the liquid phase of freon enters the cooled water from below, evaporates and into gaseous state goes up to the compressor. This is better for heat transfer.

Transitions can be taken from plastic drinking pipes PE 20*3/4’ with external thread, screwed out with a barrel of locknuts and a seal of flax and sealant. Water supply and drainage made from ordinary sewer pipes and rubber sealing cuffs inserted by surprise.

The evaporator was also mounted on L-400mm brackets.

4. TRV:

Acquired TRV from Honeywell (former FLICA). For my power, it took a 3mm nozzle to it. And a pressure equalizer.

Important: TRV during soldering cannot be overheated above +100c! Therefore, I wrapped it with a cloth soaked in water to cool it. Please do not be horrified, after the raid I cleaned it with fine sandpaper.

I soldered the equalization line tube as it should be in the installation instructions for the expansion valve.

Assembly:

Bought a kit for hard soldering Rotenberg. And electrodes 3 pieces with 0% silver content and 1 piece with 40% silver content for soldering in the compressor side (vibration resistant). With their help, I assembled the entire system.

Important: Take the Maxigaz 400 bottle (yellow bottle) right away! It is not much more expensive than Multigas 300 (red), but the manufacturer promises up to +2200c flame. But this is not enough for ¾ 'pipe. Soldered badly. I had to contrive, use a heat shield, etc. Ideally, of course, have an oxygen burner.

Yes, and you need to solder a filling pipe with a nipple to connect the hose to the system. I don't remember its exact name off the top of my head.

It was soldered at the compressor inlet. Nearby, the inlet pipe of the equalizer of the expansion valve is also visible. It is soldered after the evaporator, thermostatic expansion valve, but before the compressor.

Important: We solder the filling pipsik by first unscrewing the nipple from it. Neither from the heat, the nipple seal will definitely fail.

I did not use reducing tees, as I was afraid of a decrease in reliability from additional solder joints near the compressor. Yes, and the pressure in this place is not great.

Freon charging:

collected, but not filled The system must be evacuated with water. Better to use Vacuum pump if not, then the craftsmen adapt a conventional compressor from an old refrigerator. You can simply blow through the system with freon by squeezing out the air, but I didn’t tell you this, because you can’t do that!

Freon cylinder of the smallest capacity. The system will not need more than 2 kg at all. freon. But how rich.

I also bought a pressure gauge. But not a special freon one for $10. e., and the usual for pumping station for 3.5 u. e. I was guided by it when filling out.

I filled the system as much as possible with the help of the internal pressure of freon in the cylinder. I let it stand for a couple of days, the pressure did not drop. So there is no leak. Additionally, I missed all the connections with soapy foam, it did not bubble.

Important: Since in my case the filling nipple is soldered immediately in front of the compressor (in the future, the pressure in this place will be measured when setting up), in no case should the system be filled with liquid freon with the compressor running. The compressor will probably fail. Only in the gaseous phase - balloon up!

Automation:

You need a single-phase starting relay, and at the same time, for a very decent starting current of about 40 A! Automatic fuse From the group to 16A. Switch box with DIN rail.

I also installed two temperature switches with copelar thermal sensors. One put on the water at the outlet of the condenser. I set it to about 40 degrees to turn off the system when the water reaches this temperature. And to the outlet of water from the evaporator to 0 degrees, so that it emergency shuts down the system and does not unfreeze it by chance.

In the future, I'm thinking of purchasing a simple controller that takes these two temperatures into account. But apart from appearance and clarity of use, it also has a drawback - the programmed values ​​​​go astray even with a short power outage. While thinking.

Run (trial):

Before starting, I pumped about 6 bar of pressure from the cylinder into the system. More did not work, and there is no need. I threw a temporary wire, connected the starting capacitor. I filled the containers with water first. They stood for a day, filled and therefore, at the time of launch they had room temperature about +15s.

Solemnly turned on the machine. He was knocked out immediately. Still, the same. During this short interval, you can hear the engine buzzing, but not starting. I moved the terminals on the capacitor (for some reason there are three of them). Turned the machine back on. The pleasant rumble of a running compressor caressed my ears!

The suction pressure immediately dropped to 2 bar. Opened the freon bottle to fill the system. According to the plate, I calculated the required boiling pressure of freon.

For my required +6 inlet and +1 outlet water, a boiling point of -4c is required. Freon boils at this temperature at a pressure of 4.3 kg. see (bar) (atmospheres). The table can also be found online.

No matter how I tried to set the exact pressure, nothing worked. The system has not yet been brought to operating temperature. Therefore, premature adjustments are only approximate.

Five minutes later, the feed reached about +80 degrees. While the uninsulated evaporation pipe was covered with light frost. The water in the condenser after ten minutes to the touch has already warmed up to +30 - +35. The water in the evaporator is close to 0c. In order not to unfreeze something, I turned off the system.

Summary: Trial run showed full working capacity systems. Anomalies were not observed. Further adjustments of the expansion valve and freon pressure will be required after connecting the heating circuit and cooling with well water. So continuation of the photo essay and report in about two to three weeks when I figure out this part of the work.

By that time, I think:

1. Connect the space heating circuit and the well water heat exchange circuit.
2. Produce full cycle commissioning works.
3. Make some kind of case.
4. Draw conclusions and give a short summary.

Important: TN turned out not so small in size. By using plate heat exchangers instead of capacitive heat exchangers, you can save a lot of space.

The cost of manufacturing a heat pump with an approximate capacity of 9 kilowatt hours in terms of heat:

Capacitor:

Tank stainless steel 100 liters - 25 c.u. e.
Stainless steel electrodes - 6 c.u. e.
Stainless steel couplings - 5 c.u. e.
Services of a welder (lunch) - 5 c.u. e.
Copper pipe 12.7 (1/2”)*0.8mm. 35 meters - 105 c.u. e.
Copper pipe 10*1 mm. 1 meter - 3 c.u. e.

Air blower Du 15 - 5 c.u. e.
Safety valve 2.5 bar - 4 c.u. e.
Drain valve Du 15 - 2 at. e.

Total: 163 c.u. e. (in comparison, plate heat exchanger Danfos 389 c.e.)

Evaporator:

Plasma barrel. 120 liters - 12 c.u. e.
Copper pipe 19.2 (3/4”)*1.2mm. 25 meters - 130 USD e.
Copper pipe 6*1mm. 1 meter - 2 c.u. e.
Thermoregulatory valve Honeywell (nozzle 3mm.) - 42 c.u. e.
Brackets L-400 2 pieces - 9 c.u. e.
Drain valve Du 15 - 2 at. e
Transitions to copper (set) - 3 c.u. e.
RVS pipe 50-1m. 2 pieces - 4 cu. e.
Rubber transitions 75 * 50 2 pieces - 2 cu. e.

Total: 206 c.u. e. (in comparison, plate heat exchanger Danfos 389 c.e.)

Compressor:

Compressor little used 7.2 k.v. (25500 btu) - 30 c.u. e.
Brackets L-300 2 pieces - 8 c.u. e.
Freon R22 2 kg. - 8 at. e.
Mounting kit - 4 cu. e.

Total: 50 c.u. e.

Mounting kit:

Blowtorch ROTENBERG (set) - 20 c.u. e.
Hard soldering electrodes (40% silver) 3 pieces - 3.5 cu e.
Hard soldering electrodes (0% silver) 3 pieces - 0.5 c.u. e.
Manometer for freon 7 bar - 4 c.u. e.
Filling hose - 7 at. e.

Total: 35 c.u. e.

Automation:

Starter relay single-phase 20 A - 10 cu. e.
Built-in electric shield - 8 c.u. e.
Single-phase fuse C16 A - 4 cu. e.

Total: 22 c.u. e.

Total in general 476 c.u. e.

Important: At the next stage, more circulation pumps Calpada 25 / 60-180 60 c.u. will be required. e. and Calpeda 32/60-180 78 c.u. e. Although they will be taken out of the chapels of my boiler, they usually refer to the boiler itself.

You might think that a device based on technology conventional refrigerator will be able to perform high-quality heating not only of the pool, but of the whole house? All this is performed by a conventional heat pump, which, moreover, can be made independently at home.

If you understand the principles of its operation and design features, you can cope with its creation yourself. Which is very useful and convenient for arranging your living space.

1 Working principle

The underlying technology, in essence, is not much different from the technology for the operation of a conventional refrigerator. As you know, a refrigerator pumps heat out of the chambers to ensure a low temperature and transfers it outside through radiators.

The technology of a heat pump is also based on the same principle: for space heating, it “pumps out” heat from the ground or water, processes it and gives it to the heating system of a house, greenhouse or pool.

The refrigerant (freon or ammonia) circulates through a system consisting of an internal and external circuit. The external circuit is located in the heat intake environment. This medium can be air, earth, or water.

In fact, any natural environment has a sufficient amount of dissipated thermal energy, which is collected by the refrigerant and transferred to the system for processing. To start the processes, it is necessary that the heat exchanger raise its temperature by 4-5 degrees. This is very important point, since the heat exchanger directly affects all conditions around.

Further, from the external circuit, the heated refrigerant enters the internal circuit. The first block - the evaporator, transforms the heat exchanger from liquid state into the form of a gas. This is possible due to the fact that freon, when not high pressure external environment, has a very low boiling point.

Further, from the evaporator, freon in gaseous form enters the compressor, where the gas is compressed, as a result of which its temperature rises sharply. After that, the gas enters the third block - the condenser. In it, the gas gives up its temperature to the water - the coolant of the heating system of the house, after cooling it takes back liquid form, and recirculation is performed.

The main characteristic of the productivity of a heat pump for heating is the conversion factor, which depends on the ratio of the heat output produced by the pump to the amount of heat energy consumed.

1.1 Design of the heat pump

The design of classical heat pumps is divided into two main circuits - external and internal. Highly important role the heat exchanger plays in them as the main provoking factor. The external circuit consists of pipes through which the heat exchanger (refrigerant) circulates.

Such a circuit may different ways implementation and location, however, it always performs only one function - to circulate the refrigerant in the heat intake environment, and move the heat exchanger to the compressor. Pipes of the outer contour are made of plastic or other materials with high thermal conductivity.

The external circuit - the pump itself, consists of a condenser, compressor, evaporator and pressure reducing valve.

In addition, a hydrodynamic HP is distinguished, the design of which differs from a conventional heat pump for heating. The hydrodynamic pump consists of a power unit (engine), a heat generator, and a coupling that transfers the energy generated by the drive to the generator, where the heating fluid is heated.

1.2 Types and their differences

Depending on the type of environment in which the heat pump draws energy, the following types of HP are distinguished:

• Air-water;

The air source heat pump is the most budget option alternative heating, it can be equipped with your own hands, since for its operation there is no need to equip complex system outer contour.

However, the air pump has one significant drawback, which makes its use in our climate unjustified - with a decrease in air temperature, its efficiency sharply decreases.

If you want to make a heat pump with your own hands for heating the pool, - the best way. Moreover, for the pool, this option will be preferable, since it is quite easy to work with it and it is extremely practical.

• Water-water;

The external contour for heat intake is located in a non-freezing reservoir - artificial or natural. In terms of heat transfer, water is the most efficient medium. In practice, the use of surface water bodies is not justified, as they freeze during the cold season.

Maximum stability and efficiency of heating with a heat pump is achieved when using ground water. For this, special wells are created in which the external contour of the system is located.

Despite the fact that this technology heating is the most time-consuming, its use makes sense, since the temperature of groundwater is not subject to significant changes in different time of the year. The best option for heating the pool or small residential premises.

• Brine-water;

Soil is used for heat intake, which necessitates the creation of collectors (for horizontal placement of pipes of the external circuit), or shallow wells(for vertical placement - 1 running meter well gives 40-60 watts of heat).

This option is used everywhere - from warming up the pool, to heating the whole house. The technology got its name "brine" from the fact that a special non-freezing liquid is poured into the pipes.

There is also a Frenette heat pump - it works on a different technology, and has nothing in common with conventional heat pumps. This pump consists of two cylindrical containers - a larger one and a smaller one, while the smaller container is placed inside a large vessel.

The free space between them is filled with oil. The outer cylinder is fixedly fixed, and the inner container is connected to the drive shaft, during which, due to the friction forces arising from the rotational movements of the cylinders, the oil is heated to a very high temperature and transferred to the heating radiators.

Such a mechanism has a fairly high efficiency, and at the same time, it can be easily made by hand.

2 We make and install heat pumps with our own hands

It is quite possible to make a heat pump with your own hands, but for this you need to find a good compressor.

You can do this by visiting some local repairman household appliances where, having gutted an old air conditioner, you will get a quite high-quality compressor for a small amount (their service life is much longer than the average life of air conditioners).

As a condenser, you can use a stainless steel tank, approximately 100 liters. And for the circuit through which the heat exchanger will circulate, thin copper plumbing pipes are perfect.

DIY heat pump - manufacturing steps:

To make a Frenette heat pump with our own hands, we need to acquire the following materials:

• Steel cylinder (select the diameter based on the pump power that you need for heating: the larger working surface- the more efficient the device will be);
• Steel discs, with a diameter of 5-10% less than the diameter of the cylinder;
• Electric motor (it is best to initially select a drive with an elongated shaft, since disks will be installed on it);
• Heat exchanger - any technical oil.

The number of revolutions that the engine can produce will determine the temperature to which the Frenette pump can heat water for heating a house or a pool. In order for the water in the radiators to warm up to 100 degrees, it is necessary that the drive provide 7500-8000 rpm.

The shaft of the power unit on bearings is placed inside the steel cylinder. The place where the shaft enters the cylinder must be securely sealed, since the presence of even the slightest vibration quickly disables the mechanism.

Work disks are mounted on the motor shaft. Required distance between them can be set by screwing nuts after each disk. The number of disks is determined depending on the length of the cylinder - they must evenly fill its entire volume.

We drill two holes in the upper and lower parts of the cylinder: heating pipes, into which oil will be supplied, and a return pipe is connected to the lower hole to return the used oil from the radiators.

The entire structure is attached to metal frame. After the unit is assembled, the cylinder is filled with oil, the pipes of the heating main are connected to it and the connections are sealed.

The Frenette heat pump has a very high efficiency, which allows it to be used effectively in any heating systems. It can be used to heat any utility rooms, garages, and residential buildings. In addition, due to its compact size, such a home-made pump is great for heating a pool or a “warm floor”.

But remember that when heating the pool and other large water containers, you need a pump of sufficient power, otherwise you will simply use it for other purposes and you will not get the desired results.

2.1 Installing heat pumps

Features of installation of heat pumps depend, first of all, on the method of placement of the external circuit.

1. . For vertical way mounting are created

Catering to home furnishing hot water and heating, most often a person faces many obstacles. One of the first is the choice of energy source. If a gas pipeline is laid nearby, the issue is resolved by itself. You draw up all the necessary documents for gasification and heat the room. But what to do if there is no gasification, and will not be in the near future?

Surely you can buy gas bottle or use wood and coal, but this is not very efficient. You can also use electric heating, but the amount received at the end of the month in the receipt will be quite impressive.

Most right decision- the use of heat extracted from the bowels of the earth, air and water, which can be obtained using heat pumps.

It is very easy to create a heat pump with your own hands. All that is needed for this is to know its varieties and design features. Let's consider all this in more detail.

The division of pumps into types is carried out according to the media from which thermal energy. There are the following varieties:

How does a heat pump work?

A heat pump for heating a house with your own hands has a fairly simple principle of operation. The main components of the system are as follows:

1. Thermal pump.
2. Intake device.
3. Heat dissipation device.

All pumps operate according to the "Carnot cycle", which is as follows: a temperature-resistant liquid is supplied to the collector, which will not freeze when the temperature drops. It takes heat energy and moves it to the pump.

Once in the evaporator, the energy interacts with the refrigerant, resulting in the formation of vapor. Pressure increases, temperatures rise. Thermal energy is transferred to the room, the refrigerant becomes liquid and is again sent to the collector, thus, a closed system is obtained.

How to calculate equipment?

Any do-it-yourself home-made heat pump requires some calculations, the indicators for which are taken taking into account the heat loss of the calculated house. Of course, before installing such equipment, it is necessary to insulate the walls, floor, windows and roof of the room. The indicators of heat demand for individual buildings are as follows:

1. for old Khrushchev - 75 W / m.
2. for newer buildings - in the region of 50 W / m ".
3. for buildings using the latest technologies - 30 W / m » .

Important! The calculation and order of such an installation is best carried out even before the construction of the building. This will make it possible to choose the most suitable heating system.

Most users believe that the most suitable system is a floor with water heating, the calculation of the power of which is made taking into account floor covering. The most suitable option is ceramic tiles.

Creating a heat pump with your own hands

Making a heat pump with your own hands is quite simple, but it will require a good compressor, which you can buy at any repair shop. The ideal capacitor is a tank of of stainless steel volume of 100 l. and more. A heat pump for heating a house with your own hands has the following manufacturing steps:

To make a Frenette heat pump, we need:

1. A cylinder made of steel, the diameter of which is directly proportional to the power of the pump.
2. Discs made of steel, the diameter of which will be 5-10% less than the d of the cylinder.
3. Electric motor. It is advisable to buy a drive with an extended shaft, on which disks will be installed in the future.
4. Heat exchanger.

The output temperature will directly depend on the engine power. To heat water to a temperature of 100 C 0, the drive speed should be in the range of 7.5-8 thousand per minute. The shaft entry point is sealed, as the presence of any backlash will quickly wear out the mechanism. Working discs are mounted on the motor shaft, the distance between which is adjusted by installing nuts.

Two holes are made in the cylinder, to which pipes will be connected. After complete assembly the cylinder is filled with oil, all pipes are connected and sealed. If you still have questions about its design, then write in search engine- "do-it-yourself heat pump drawing" and get acquainted with all this in more detail.

Advantages of heat pumps

There are many advantages to this type of pump. The main one is the presence of a control unit, which makes it possible to control the entire process. In addition, it can be used to adjust the degree of heating, making it larger or smaller. Installed special sensors constantly monitor the temperature level, if necessary, giving appropriate signals. After reaching the minimum or maximum, the pump stops or vice versa, it starts.

Important!Modern pumps have great functionality. Now with their help you can not only heat the house, but also ensure the constant presence of hot water in it.

In addition, heating using such a pump can both heat and cool the air in the room. To do this, a reverse valve is installed in it, which allows you to do both one and the other operation. Thus, by installing such a system in your home, you can get an installation that will be useful all year round.

Yes, undoubtedly, most users point to its main drawback - a rather high price range. In this case, it is worth remembering the fact that spending only once, you long years do not wake up to buy anything and worry about anything, that is, further - only savings.

Installation work

After manufacturing the main part of the system, it is necessary to connect it to the heat distribution and intake device. The first process is quite easy, but the second is quite laborious. Of course, a person who has assembled a heat pump device with his own hands will connect it independently, without outside help. Installation work directly depend on the type of pump, since each of them has certain features.

Costs and payback

Of course, the installation of this equipment implies impressive costs, since it will take much more to purchase its components. Money, unlived to buy electric boiler similar power. Many are interested in the question, is it profitable? Yes, it's profitable. So, for example, the installation of this type of system in a house with an area of ​​100 m 2 will pay off in one and a half to two years, and in the future there will be continuous savings. In addition, the heat pump can be used as an air conditioner, allowing you to significantly lower the temperature in the room.

Safety and environmental friendliness

For those people who care about the environmental friendliness and safety of their premises, the most suitable option for space heating is a heat pump. This is due to the fact that it is completely harmless and does not emit any harmful substances into the atmosphere at all. The possibility of fire and explosion is practically excluded, since overheating of the parts included in the system is practically impossible.

Video - do-it-yourself heat pump

A heat pump is an interesting thing, but expensive. approximate cost equipment + external circuit devices from $300 to $1000 per 1 kW of power. Knowing the “handiness” of the Russian people, it is easy to assume that more than one hand-made heat pump is already working in the vastness of our vast and varied climate. Most often found homemade devices, which were made by "refrigerators". And this is understandable, because the heat pump and freezer they work on the same principle, it’s just that the system of thermal installations is focused on collecting heat, and not on removing it, and the compressor is used with more power.

What can be the source of heat for a heat pump

Heat for space heating can be taken from the air outside. But here, difficulties will inevitably arise during operation: even average daily temperature fluctuations are too large, not to mention the fact that the heat pump shows normal efficiency at temperatures above 0 o C. And how many regions do we have in winter such a picture? In the spring, and even then not early, and not throughout the territory, and not constantly.

A heat source located in the water looks much more acceptable. If there is a river, a lake or a pond of a decent depth nearby, this is just great: you can simply drown the pipeline. It is only important that fishermen with donkeys do not fish there.

Another good option is a well, but there is a chance that the water level will drop and you will have to look for another source. But while everything is fine, it will work well: average temperature water in underground horizons 5-7 o C. This is more than enough for the operation of the heat pump.

You may be surprised, but you can also use the sewer - there the temperatures are higher than in the wells. The pipeline can be placed in sewer pit or a well, but on condition that it is constantly covered with water. And the pipe will need to be chosen chemically resistant.

A horizontal underground collector is an extremely laborious task: it will be necessary to remove the soil from several acres to a depth below the freezing point. These are very large volumes that cannot be mastered alone or even with an assistant. And, as practice has shown, in our climatic conditions such systems are ineffective: winters are too severe.

With vertical collectors, things are no better - it is unlikely that it will be possible to do without drilling equipment. The number and depth of wells depend on the soil: the spread of possible heat removal from a well meter is very large. From 25 W/m in dry crushed stone and sandy soil, up to 80-85 W/m in wet crushed stone and sandy soils or in granite. Accordingly, the difference in the length of the wells is 3 times or more.

Here is a scheme for heating a house with a heat pump. When using, as in the example described, two wells and in the absence of a closed loop, the distance between the two wells must be at least 20 meters. And you need to take into account the direction of the flow, so that cold water from the pump did not reduce the temperature in the “donor” well

In the described example of a homemade heat pump, the heat source is a well with a good water flow rate. Water arrives so quickly that it covers the consumption for domestic needs and it is enough to transfer the required amount of heat (the required water supply rate was calculated, and the pump was selected accordingly). But the source of heat for this modification can be any of those described above, except for air. Having decided on the source of heat, it will be possible to make a heat pump for heating the house.

Heat pump water-to-water from air conditioner compressor

This air conditioner heat pump is easy to make, but you'll need some help. good master for the repair of refrigeration equipment. To make, you need to purchase:

All these components with payment for the work of the refrigerator (for assembly and soldering, filling freon) amounted to about $ 600. Plus the cost of personal time for the arrangement of the input circuit and assembly.

Now let's start making the heat pump itself.

Pay more attention to vibration isolation and noise absorption: if the device is in the house, they will not additional measures by their neutralization decently act on the nerves.

In the described example, water is pumped from a well, the aquifer is located at a depth of 4 meters. One pump lifts it and delivers it to the heat pump, the water is discharged into the second well. But it is possible to organize a closed circuit, then it will be necessary to calculate the power of the circulation pump.

This is after the work of the "refrigerator"

From the experience of operating a do-it-yourself heat pump

As practice has shown, the performance of the presented option is low: 2.6-2.8 kW. Talk about high efficiency this heat pump is not necessary: ​​on an area of ​​​​60 m 2 at -5 o C on the street, it itself supports +17 o C. But the system was considered and mounted under the boiler - radiators, at an incoming temperature of +45 o C, they simply cannot give out more . The system in the house was old and the number of radiators was not increased, but so far in the cold they were warmed up by the stove.

If a regenerative heat exchanger is added to the design, this will increase efficiency by 10-15%. Given that the costs are small, you can do it. You will need two copper tubes of 1.5 meters each. One with a diameter of 22 mm, the second - 10 mm. A 4-core conductor (length 3-4 meters, diameter 4 mm) is wound on a thinner one to increase the heat exchange area, its ends are soldered to the tube so that they do not unwind. The tube with the wound wire is carefully inserted into the larger diameter tube. It must be installed between the compressor and the evaporator. The improvement is minor, but it significantly improves efficiency. True, at certain conditions unsafe: warm freon can get into the compressor, which will lead to its failure.

The second option to increase efficiency, safer and no less effective, is to build in an additional heat exchanger for heating water or glycol.

What to look for if you decide to make a heat pump with your own hands. There are a few things that can only be learned through experience:

• • The starting currents of this particular installation were very decent. There were not always enough network resources to start the installation. Therefore, if you make a serious installation, it is better to take a three-phase compressor, and, accordingly, bring a three-phase input. Yes, it is not cheap, but for a stable start of a single-phase compressor, an electronic stabilizer of decent power is required, which cannot be called cheap either.
  • A heat pump on a finished radiator system will not normal temperature in room. They are designed for a different temperature of coolants, which these installations, especially home-made ones, are extremely rarely able to give. Therefore, either upgrade the system (by adding at least the same number of radiator sections), or install water floors.
  • If there are three rings of water in the well, this does not mean that it has a large debit. You need to know how much water he is able to give with its constant selection.

Results

Undoubtedly, the cost of a heat pump from an air conditioner is several times lower than ready-made factory options, even those made in China. But there are a lot of nuances here: you need to take care of the source and amount of heat supplied, correctly calculate the length of heat exchangers (coils), install automation, provide guaranteed power, etc. But if you are able to solve these problems, then it is undoubtedly beneficial. Let me give you advice: in the first year it is very desirable to have backup heating, and it is better to carry out tests and trial run in the summer so that there is time to finalize the unit before the start of the heating season.

Unlike these devices alternative energy, as solar battery and wind generator, heat pump is less known. And in vain. The most common "soil-water" scheme works stably and does not depend on the weather or climatic features. And you can make it yourself.

A bit of theory

It is easiest to use the natural heat of the earth to heat your home if there are geothermal waters in the region (as they do in Iceland). But such conditions are very rare.

And at the same time, thermal energy is everywhere - you just need to extract it and make it work. This is what a heat pump is for. What does it do:

• takes energy from low-temperature natural sources;
• accumulates it, that is, raises the temperature to high values;
• gives it to the coolant of the heating system.

Basically, it is used standard scheme compressor refrigerator, but "vice versa". Natural coolant circulates in the primary circuit. It is closed to a heat exchanger that acts as an evaporator for the second circuit.

1 - earth; 2 - brine circulation; 3 - circulation pump; 4 - evaporator; 5 - compressor; 6 - capacitor; 7 - heating system; 8 - refrigerant; 9 - throttle

The second circuit is the heat pump itself, inside of which there is freon. The heat pump cycle consists of the following steps:

1. In the evaporator, freon is heated to the boiling point. It depends on the type of freon and the pressure in this part of the system (usually up to 5 atmospheres).
2. In a gaseous state, freon enters the compressor and is compressed to 25 atmospheres, while its temperature rises (the greater the compression, the higher the temperature). This is the phase of heat accumulation - from a large volume with a low temperature, a transition to a small volume with a high temperature.
3. The pressurized gas enters the condenser, in which heat is transferred to the heat carrier of the heating system.
4. After cooling, freon enters the throttle (aka flow regulator or expansion valve). In it, the pressure drops, freon condenses and returns to the evaporator as a liquid.

Where is the best place to "take away" heat

In principle, there are three environments from which heat can be “taken away”:

1. Air. At normal pressure, all types of freons boil at negative temperatures(e.g. R22 approx. -25 °C, R404 and R502 approx. -30 °C). But for circulation in the system, it is necessary to create excess pressure already in the first phase - evaporation. The same 4 atmospheres in the evaporator requires that the outdoor air temperature be at least 0 °C for R22 and -5 °C for R404 and R502. In our regions, this type of heat pump can be used for heating in the off-season and for hot water in the warm season.

2. Water. This is a more stable source of heat, provided that the reservoir does not freeze to the bottom in winter. But the house should not just be located next to a lake or river, but be on the first line.

3. Earth. The most stable source of thermal energy. You can use two schemes - horizontal and vertical. Horizontal seems easier themes that does not require drilling. But you have to do a lot earthworks for digging a system of trenches to a depth below the level of soil freezing (for middle latitudes, it ranges from 1 meter in the west of the European part of the country and up to 1.6-1.8 closer to the Urals, in Siberia the situation is “even worse.” The vertical scheme is more universal and effective, but requires drilling to a considerable depth, although several shallow wells can be used instead of one deep well.

circuit diagram

The heat pump circuit itself is simple: evaporator - compressor - condenser - throttle - evaporator.

The “heart” of the circuit is the compressor. You can buy a new one, but it's cheaper to find a used one. Naturally, we are not talking about low-power compressors. domestic refrigerators, but about models installed in split systems. It is necessary to focus not on the power consumption, but on the power in heating mode (which is 5-20% higher than in cooling mode).

The compressor model is selected according to the ratio of 1 kW per 10 square meters. meters of heated area.

Attention! Power can be indicated not only in kW, but also in BTU (English unit of measure for thermal energy, adopted for climate technology). Recalculation is easy to do - divide the value in BTU by 3.4.

When calculating the parameters of the heat pump, including heat exchangers, use software, intended for modeling, calculations and optimization of cooling systems, for example, CoolPack

Already at the stage of calculations (more precisely, when setting the "introductory"), you can optimize the system by choosing the optimal thermal conditions.

The use of a heat pump is effective for low-temperature heating systems, for example, for underfloor heating with a temperature not exceeding 35-40 °C. By the way, the same temperature is recommended for medical requirements for the DHW system.

For each type of freon there is optimal temperatures"input" and "output", more precisely, boiling and condensation, but the difference in all of them is no more than 45-50 ° C.

It would seem that increasing the temperature at the outlet of the heat pump will have a positive effect, but this is not so. The temperature difference will also increase, which will lead to a decrease in COP (coefficient of conversion, or efficiency of a heat engine). In addition, this will require the use of a more powerful compressor and additional expense electricity.

The ideal COP cannot be achieved (losses in the compressor, power consumption, heat losses during transportation within the system, etc.), so real values usually lie between 3 and 5.

There is another way to increase efficiency - the use of a bivalent heating scheme.

In reality, the operation of the heating system at full capacity is needed only for 15-20% of the entire season. During this time, additional heating devices(e.g. ceramic heater or convector). Reducing the design heat output by up to 80% will save on the compressor, reduce the depth of the well or the length of the pipes horizontal layout, reduce energy consumption for servicing the heat pump itself.

The design of a horizontal or vertical ground heat exchanger depends on the given nominal power of the heat pump and the COP. On average, 20 W are removed from each meter of the "horizon" (with a pipe laying step of at least 0.7 m), and from the "vertical" - 50 W. But specific values ​​​​depend on the type of rock and its moisture content. Groundwater has the best values.

Interesting! There are other ground heat exchangers - "spiral" or "basket". In fact, this is a vertical probe from a pipe in the form of a spiral, which allows to reduce the depth of drilling.

After determining the length of the horizontal loop or the depth of the vertical probe, the dimensions of the evaporator and condenser are calculated.

Manufacturing of the evaporator and condenser

You can buy ready-made heat exchangers for both the evaporator (under low pressure) and the condenser (with pressure up to 25 bar). But it's cheaper to make them from copper tube for air conditioners (which is designed specifically to work with refrigerants at high pressure) and improvised containers.

Important! Plumbing copper pipe is not as "clean" and flexible. It is worse to solder and roll during installation.

The surface area of ​​the heat exchanger is calculated, which is directly proportional to the heat release power and inversely proportional to the temperature difference of the heat carriers at the inlet and outlet of each connected circuit (ground and heating systems).

Knowing the pipe diameter and surface area, determine the length of each coil for the evaporator and condenser.

It is better to make a container for a condenser from stainless steel (the temperature of the incoming freon vapor can be quite high):

• take a tank suitable capacity(to fit a spiral of copper tube);
• place a coil in it (inlet at the top, outlet at the bottom);
• bring out the ends of the copper tube for connection to the compressor and expansion valve (by soldering or flange);
• make adapters in the tank for connecting pipes of the heating system;
• seal the lid.

The evaporator runs on more than low temperatures, so you can take a cheaper one for it plastic container, into which adapters are cut for connection to the ground circuit. It also differs from the condenser in the location of the heat exchanger coil - the inlet (the liquid phase of freon from the expansion valve) is from below, the outlet to the compressor is from above.

Circuit mounting

After the manufacture of heat exchangers, the gas-hydraulic circuit is assembled:

• install the compressor, condenser and evaporator in place;
• soldered or flanged copper pipes;
• connect the evaporator to the ground circuit pump;
• connect the condenser to the heating system.

1 - circulation pump of the soil circuit; 2 - evaporator; 3 - exit of the soil circuit; 4 - thermostatic valve; 5 - compressor; 6 - to the heating system; 7 - capacitor; 8 - heating system return

The electrical circuit (compressor, ground loop pump, emergency automation) must be connected via a dedicated circuit, which must withstand fairly high starting currents.

Be sure to use the automatic protection, as well as emergency turn-off from the temperature switch: at the water outlet from the condenser (in case of overheating) and the outlet of the brine from the evaporator (in case of subcooling).