• Why is a heat pump need­ed? When should you choose a heat pump? Advan­tages

  • How a heat pump works

  • Ener­gy source. Require­ments

    • well

    • earth con­tour

    • water

    • warm air

  • Peak elec­tri­cal heat­ing. Why do you need

  • Air con­di­tion­ing, pas­sive and active. Prin­ci­ple

  • Heat­ing sys­tem — heat pump and under­floor heat­ing

Why is a heat pump need­ed? When should you choose a heat pump? Advan­tages

heat pump, principle of operation A heat pump is a mod­ern source of ener­gy used for the oper­a­tion of air con­di­tion­ing sys­tems, heat­ing, hot water sup­ply. Unlike oth­er heat gen­er­a­tors (gas, diesel, elec­tric), the heat pump “pumps out” the ener­gy accu­mu­lat­ed dur­ing the warm sea­son from the envi­ron­ment — soil, rock, water.

What are the ben­e­fits of using a heat pump? First of all, it is an increase in the lev­el of com­fort. By choos­ing a heat pump over an oil-fired sys­tem, you will reduce your home­’s fire haz­ard, get rid of the chim­ney, diesel smell, and the need to remem­ber to order deliv­ery on time.

If you would like to install a sys­tem that runs on elec­tric­i­ty, but there is not enough con­nect­ed elec­tri­cal pow­er at home for this, a heat pump can solve this prob­lem — a quar­ter of the pow­er need­ed for a tra­di­tion­al heat­ing sys­tem is enough to use it. As an exam­ple, you can see a Swedish-made Ther­mia heat pump on the dis­trib­u­tor’s web­site.

Thus, the use of a heat pump also saves ener­gy and mon­ey. In Rus­sia today, the cost of heat pro­duc­tion depends sig­nif­i­cant­ly on the type of fuel: elec­tric­i­ty is the most expen­sive, fol­lowed by diesel fuel and gas. But ener­gy prices are con­stant­ly chang­ing, and the dif­fer­ence between them is shrink­ing. At the same time, the dif­fer­ence in the cost of installing a heat pump with a ground heat exchang­er and a diesel-fueled boil­er house with a fuel econ­o­my, a chim­ney, an auto­mat­ic con­trol sys­tem will pay off in 3–5 years.

Popular Models


Daikin
Heat pump with elec­tric dri­ve Viess­mann 300 BW 104

Daikin
Mit­subishi Elec­tric invert­er heat pump MSZ-FD35VA/MUZ-FD35VABH

Daikin
Heat pump Fhp 9

Heat pumps elec­tric: all mod­els

How a heat pump works

The source of heat can be rock, earth, water, air.

The coolant heats up by sev­er­al degrees, pass­ing through an exter­nal cir­cuit laid in the ground or a reser­voir. Inside the heat pump, the heat­ing medi­um pass­es through a heat exchang­er (evap­o­ra­tor) and releas­es the col­lect­ed heat to the inter­nal cir­cuit of the heat pump. The inter­nal cir­cuit of the heat pump is filled with a refrig­er­ant hav­ing a low boil­ing point, which, pass­ing through the evap­o­ra­tor, turns from a liq­uid state into a gaseous state at a tem­per­a­ture of ‑5°C and low pres­sure. From the evap­o­ra­tor, the gaseous refrig­er­ant enters the com­pres­sor, where it is com­pressed to high pres­sure and high tem­per­a­ture. Then the hot gas enters the sec­ond heat exchang­er — the con­denser, where heat exchange takes place between the hot gas and the heat car­ri­er from the return pipe of the house heat­ing sys­tem. The refrig­er­ant, giv­ing off heat to the heat­ing sys­tem, cools and turns into a liq­uid, and the heat car­ri­er of the heat­ing sys­tem enters the heat­ing devices. After pass­ing through the con­denser, the liq­uid refrig­er­ant can be fur­ther cooled and the heat­ing sys­tem direct water tem­per­a­ture increased by means of an option­al sub­cool­er. The refrig­er­ant pres­sure, how­ev­er, is still high. When the refrig­er­ant pass­es through the pres­sure reduc­ing valve, the pres­sure decreas­es, the refrig­er­ant enters the evap­o­ra­tor, and the cycle repeats again.

heat pump device

Necessary requirements for the energy source

The source of ener­gy can be soil, rock, lake, in gen­er­al, any source of heat with a tem­per­a­ture of 1 degree Cel­sius and above, avail­able in win­ter. It can be a riv­er, the sea, the exit of warm air from a ven­ti­la­tion sys­tem or any indus­tri­al equip­ment.

The exter­nal cir­cuit, which col­lects the heat of the envi­ron­ment, is a poly­eth­yl­ene pipeline laid in the ground or in water. The heat car­ri­er is a 30% solu­tion of eth­yl­ene gly­col (or eth­yl alco­hol).

well Well

When using rock as a heat source, the pipeline is low­ered into the well. It is pos­si­ble to drill sev­er­al shal­low wells — this may be cheap­er than one deep one. The main thing is to get the total esti­mat­ed depth.

For pre­lim­i­nary cal­cu­la­tions, the fol­low­ing ratio is used — 50–60 W of ther­mal ener­gy per 1 meter of the well. That is, to install a heat pump with a capac­i­ty of 10 kW, a well with a depth of 170 meters is required.

earth con­tour

earth contour When lay­ing the con­tour in the ground, it is desir­able to use a site with moist soil, best of all with close ground­wa­ter. The use of dry soil is also pos­si­ble, but this leads to an increase in the length of the con­tour. The pipeline should be buried to a depth of approx­i­mate­ly 1 m, the dis­tance between adja­cent pipelines should be approx­i­mate­ly 0.8–1.0 m.

The spe­cif­ic ther­mal pow­er of the pipeline laid in the ground is 20–30 W/m. Those. to install a heat pump with a capac­i­ty of 10 kW, 350–450 m of the ther­mal cir­cuit is enough, for which a plot of 20 x 20 sq. m.

Spe­cial soil prepa­ra­tion is not required; the pipeline does not have an effect on plants if cal­cu­lat­ed cor­rect­ly.

Water


water The near­est body of water is an ide­al source of heat for a heat pump. When using lake or riv­er water as a source of heat, the cir­cuit is laid on the bot­tom. This option is ide­al from every point of view — “high” ambi­ent tem­per­a­ture (water tem­per­a­ture in the reser­voir is always pos­i­tive in win­ter), short exter­nal cir­cuit, high ener­gy con­ver­sion effi­cien­cy of the heat pump.

There is approx­i­mate­ly 30 W of ther­mal pow­er per 1 meter of pipeline. Thus, to install a heat pump with a capac­i­ty of 10 kW, it is nec­es­sary to lay a 300-meter long cir­cuit in the lake.

In order for the pipeline not to float, it is nec­es­sary to install about 5 kg of car­go per 1 lin­ear meter of the pipeline.

Warm air

warm air There is also a spe­cial mod­el of a heat pump with an air heat exchang­er for obtain­ing ther­mal ener­gy from the air, for exam­ple, from the exhaust of a ven­ti­la­tion sys­tem. It can be used in man­u­fac­tur­ing plants that pro­duce large amounts of warm air (bak­ery, ceram­ics, etc.).

Such a mod­el is also use­ful for a coun­try house — for the oper­a­tion of the hot water sup­ply sys­tem in the sum­mer.

Why do you need peak elec­tric heat­ing

Elec­tric heaters are installed in almost all mod­els of heat pumps. This is due to the fact that when choos­ing heat­ing equip­ment, the cal­cu­la­tion of the rat­ed pow­er when choos­ing heat­ing equip­ment is done tak­ing into account the cov­er­age of the heat load on the cold­est days, for exam­ple, for St. Peters­burg, the min­i­mum design tem­per­a­ture is ‑26 ° C.

But this tem­per­a­ture lasts only a few days a year, which means that the poten­tial of the heat pump will prac­ti­cal­ly not be used. It is eco­nom­i­cal­ly more prof­itable to pur­chase a heat pump of less pow­er, and on the cold­est days to use elec­tric heat­ing.

The com­bi­na­tion of two heat sources — gen­er­at­ing cheap ener­gy, but expen­sive (heat pump), and cheap, but gen­er­at­ing expen­sive ener­gy (elec­tric heater) can reduce the cost of cap­i­tal expen­di­tures and increase the pay­back peri­od of the heat pump instal­la­tion.

To select the pow­er ratio of the heat pump / elec­tric heater, a spe­cial inte­grat­ed graph is used, which is uni­ver­sal for all regions of Rus­sia.

The prin­ci­ple of con­di­tion­ing (active and pas­sive)

In win­ter, the heat pump trans­fers heat from the envi­ron­ment, which is then used in the heat­ing sys­tem. In sum­mer, on the con­trary, the “cold” from the well (7–9°C) is trans­ferred to the premis­es of the house. The prin­ci­ple of oper­a­tion of the sys­tem is approx­i­mate­ly the same, only fan coil units are used instead of radi­a­tors. With pas­sive cool­ing, the coolant sim­ply cir­cu­lates between the fan coil units and the well, i.e. cold from the well direct­ly enters the air con­di­tion­ing sys­tem — the com­pres­sor does not work). If pas­sive cool­ing is not suf­fi­cient, the heat pump com­pres­sor is switched on, which addi­tion­al­ly cools the heat­ing medi­um.

Water heat­ed floor and heat pump

The heat pump and the under­floor heat­ing sys­tem seem to be spe­cial­ly designed for each oth­er. The tech­ni­cal fea­tures of the heat pump are such that the tem­per­a­ture sup­plied to the heat­ing sys­tem is usu­al­ly not high­er than 55°C, and the return water tem­per­a­ture should not be high­er than 50°C. When using tra­di­tion­al radi­a­tors, care­ful cal­cu­la­tion of heat­ing devices is nec­es­sary. For a warm floor, this tem­per­a­ture is quite enough.

By installing a heat pump in an under­floor heat­ing sys­tem, ener­gy will not only be eco­nom­i­cal­ly pro­duced, but also eco­nom­i­cal­ly dis­trib­uted. A heat pump saves up to 80% of ener­gy com­pared to using tra­di­tion­al heat sources, and a warm floor saves 10–15% of ener­gy com­pared to radi­a­tor heat­ing sys­tems.

Popular Models


Daikin
Gas absorp­tion boil­er Robur

Gas heat pumps: all mod­els

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