Feature at some common heat pump refrigerants , R134a has a boiling point of -26.3 ° C and R410A has a boiling point of -48.5 ° C . Clearly at those temperatures it is very easy to extract thermal energy - even at very low outdoor temperatures , which clients often also don ’ t understand .
Heat naturally flows from a higher to a lower temperature as the laws of thermodynamics primarily teaches us . Heat pumps ‘ pump ’ this heat in a particular direction , using a relatively small amount of energy . Heat pumps can also transfer heat from natural sources in the surroundings , such as the air , ground , or water , or from man-made heat sources such as industrial or domestic waste heat from a building or an industrial application and vice versa for cooling .
A heat pump in even more simple terms transports heat . This is the defining characteristic of all these device types . They function in the same way as a compression refrigeration system , except that the focus is not on the evaporator side ( cooling ), but on the condenser side where the heating effect is created . The essential principle remains the same : evaporation of refrigerant in the evaporator , increase of pressure and hence temperature in the compressor , dissipation of the gained heat by liquefying the refrigerant in the condenser , and subsequent expansion of the refrigerant through the throttle / expansion valve . The refrigerants used are also hardly any different from those used in an ordinary refrigeration plant . The preferred refrigerants for heat pump applications are typically R407C , R410A and R134a .
" A critical aspect of the heat pumps is of course how energy efficient they are "
No matter what mode a heat pump is functioning in , overall , this operation becomes energetically attractive if the total energy output becomes greater than the energy used to drive the heat pump , and economically attractive if the total lifecycle cost ( including installation , maintenance , and operating costs ) is lower than that of competing devices .
The most common heat source for a heat pump is air , although water is also used in many applications . During the past decade , ground or geothermal resources have received increasing attention as a heat source , particularly in residential , commercial , and institutional applications overseas , where district heating and cooling engineering is the norm .
On a commercial scale all the basic characteristics of a heat pump are similar to those in the residential or domestic sector ,
Siemens Danfoss
A commercial heat pump / chiller installation .
Industrial processes provide excellent conditions for waste heat recovery that can be used as an energy source for a heat pump .
however commercial and industrial use today is seeing far more source energy derived from waste heat , excess hot water , steam , or humid air and can include various heat exchanger configurations as well .
Heat pumps can be classified into four main categories depending on their operational function :
• Heating-only heat pumps for space heating and / or water heating applications
• Heating and cooling heat pumps for both space heating and cooling applications
• Integrated heat pump systems for space heating and cooling , water heating , and sometimes exhaust air heat recovery
• Heat pump water heaters for water heating
A critical aspect of the heat pumps is of course how energy efficient they are as this technology has become essential to the modern heating and cooling requirements of the residential and commercial spaces and are further typically
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