Calorex Pro-Pac 140, Owners & Installation Manual

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COLD LIQUID
REFRIGERANT
3
4
COOL GAS
AMBIENT
AIR
1
2
COMPRESSOR
EVAPORATOR
HIGH PRESSURE SIDE
CONDENSED
REFRIGERANT
WATER IN
HOT GAS
WATER OUT
HEAT
EXCHANGER
LOW PRESSURE SIDE
EXPANSION
VALVE
COLD LIQUID
REFRIGERANT
THE HEAT PUMP CYCLE
Coefficient of Performance
The efficiency of a heat pump is usually called its ‘Coefficient of
Performance’ – (C.O.P.) which is simply a ratio of heat output to energy
input, both being expressed in kW. Thus a heat pump absorbing 1 kW
of electricity, collecting 4 kW of energy from the air, and delivering
5 kW of heat to the pool water is said to have a C.O.P. of 5:1.
Naturally, this ratio will vary according to the temperature of the water
and the ambient air.
1. THE EVAPORATOR collects the heat from the
outside ambient air, pre-heated by the sun. In the
Calorex swimming pool heat pumps, high volumes of
outside air are drawn into the unit by the fan expelled
through the evaporator fins. The evaporator has liquid
refrigerant passing through it which is at a considerably
lower temperature than the ambient air. Therefore
the air gives up its heat to the refrigerant which then
vaporizes. This preheated vapour now travels to –
2. THE COMPRESSOR where it is compressed and
upgraded to a much higher temperature. The hot
vapour now enters –
3. THE CONDENSER where it is surrounded by the
pool water. The heat is given up to the cooler pool
water and the now cold refrigerant returns to its former
liquid state but still under high pressure from the
compressor.
This pressure is released by passing the liquid through –
4. THE EXPANSION DEVICE and from there, now at normal
pressure, it is returned to the evaporator and the cycle starts
again.
Note that during the cooling cycle this process is reversed
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SD566250 ISSUE 35