Operation Of Heat Pumps; Operating Principle; Description Of Operation - hajdu HPT300 Installation, Operating And Maintenance Manual

HPT 300 • HPT 300C

3. OPERATION OF HEAT PUMPS

At first sight, the HPT300(C) heat pump water heater is similar to traditional electric hot
water tanks. During its normal operating cycle, the HPT300(C) connected to household
pipeline and electrical power system does not use as much electric power for the direct
heating of water as traditional electric hot water tanks, but rather, it uses energy in a
more reasonable and efficient way, reaching the same result with an energy use of less
than 70%, as compared to the traditional electric hot water tank.
Heat pump is named after the fact that it is capable to transfer heat from a heat source
of lower temperature to a heat source of higher temperature, i.e. it reverses natu-
ral flow of heat, which goes the higher temperature source to the lower temperature
one, as we already know. The application of the heat pump brings the benefit that it
is able to transfer more energy (in form of heat) than the energy it takes for its opera-
tion (in form of electric power). This way, heat pump is able to extract energy from heat
sources existing in its environment without "expenditure", depending on the type and
availability of the heat sources.
The HPT300(C) heat pump water heater extracts heat from stuffy internal air to be re-
freshed, thus it increases the efficiency of water heating. It is possible to select from
several different configurations for the use of environmental air, which enables various
applications of the appliance adjusted to the different operating conditions.
The HPT300(C) heat pump water heater has been planned and manufactured to speci-
fications relating to the energy performance of buildings. The appliance eables a more
rational energy use and results in operational cost savings. As opposed to other alter-
native systems used to produce sanitary hot water, heat extraction from free energy
sources definitely reduces the environmental effects of emissions into the atmosphere.
Based on the facts mentioned above, the "energetic capacity" of heat pumps is based
on heat transfer through heat extraction from a free source (in this case, the environ-
mental air) with lower temperature than the material to be heated (in this case, the
water in the tank of the water heater). Electricity is required for the operation of the
compressor (that causes the change of physical state of the cooling fluid in the cooling
circuit), and thus, the transfer of heat energy. The cooling fluid passes along a closed
hydraulic circuit, where the fluid changes into liquid or gaseous physical state, subject
to its temperature and pressure. The main components of the hydraulic circuit (Figure
3.2.-1) are as follows:
1 – compressor that enables the completion of the cycle by increasing the pressure
and the temperature of the cooling fluid (which is of gaseous physical state in this
cycle).
20

3.1. Operating principle

3.2. Description of operation