Function - Calorex PPT8 Installation Manual

Installation Manual
PPT8/12/16/22L/LY

1.2 Function

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
vaporises.This preheated vapour now travels to -
AMBIENT
AIR
4. THE EXPANSION DEVICE and from there,
now at normal pressure, it is returned to the
evaporator and the cycle starts again.
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.
This ratio will vary according to the temperature of the water and the ambient air.
Calorex Heat Pumps Ltd. · The Causeway, Maldon, Essex CM9 4XD, UK · Tel: +44 (0)1621 857 171
The Calorex Swimming pool heat pump provides thermodynamic heating by
means of a vapour compression cycle, (similar to that employed in a
conventional refrigerator), in addition to acting as an active solar collector.
THE HEAT PUMP CYCLE
COMPRESSOR
2
COOL GAS
1
EVAPORATOR
COOL LIQUID
REFRIGERANT
EXPANSION
VALVE
LOW PRESSURE SIDE
Page 5
2. THE COMPRESSOR where
it is compressed and upgraded
to a much higher temperature.
The hot vapour now enters -
HOT GAS
3
HEAT
EXCHANGER
CONDENSED
REFRIGERANT
4
HIGH PRESSURE SIDE
3. THE CONDENSER where it is surrounded by
the pool water. The heat is given up to the cooler
pool water and the now cooler refrigerant returns
to its former liquid state but still under high
pressure from the compressor.
This pressure is released by passing the liquid
through -
POOL
WATER OUT
POOL
WATER IN
R