Protection Systems - AQUA FORTE ZWPA Serie Manuel D'installation Et D'utilisation

5.1 Protection systems

Water flow switch
Equipped w ith flow s w itch the heat pump w ill not w ork w hen the filter pump is not w orking (and the
water is not circulating). This system prevents the heat pump from heating only the water present in the
heat pump itself. The protection also stops the heat pump if water circulation is cut off or stopped.
Refrigerant gas high and low pressure protection
The high pressure protection makes sure the heat pump is not damaged in case of over pressurisation of
the gas. The low pressure protection emits a signal when refrigerant is escaping from the conduits and the
unit can not be kept running.
Overheating protection on the compressor
This protection protects the compressor from overheating.
Automatic defrost control
When the air is very humid and cold, ice can form on the evaporator. In that event, a thin layer of ice
appears that will grow increasingly bigger as long as the heat pump is running. When the temperature of
the evaporator has become too low, automatic defrost control will be activated, which will reverse the heat
pump cycle so that hot refrigerant gas is sent through the evaporator during a brief period of time to
defrost it.
Temperature difference between inflowing and outflowing water
During normal operation of the heat pump, the temperature difference between inflowing and outflowing
water will approximate 1 to 2℃.In the event that the pressure switch does not work and that the water
stops circulating, the temperature probe monitoring the outflowing water will always detect a rise in
temperature. As soon as the temperature difference between inflowing and outflowing water exceeds
13℃, the heat pump will be automatically turned off.
Low temperature cut-out
If, during cooling, the temperature of the outflowing water reaches 5℃ or drops below this temperature,
the heat pump will turn itself off until the water temperature reaches or exceeds 7℃ again.