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4. Safety and Control Systems
Heat pumps are equipped with the following standard safety control systems:
4.1 Water Flow Switch
The water flow switch ensures that the heat pump does not work when the filter pump is
faulty (and the water is not circulating). This control system also stops the heat pump if the
water circulation is cut off or stopped.
4.2 Refrigerant Gas High-and-Low Pressure Protection
The high pressure protection system ensures the heat pump is not damaged in case of
over-pressurization of the gas. The low pressure protection emits a signal when refrigerant
is escaping from the conduits and the unit cannot function.
4.3 Overheating Protection on the Compressor
This protects the compressor from overheating.
4.4 Automatic Defrost Control
When the air is very humid and cold, ice can form on the evaporator. When this happens,
a thin layer of ice appears that will become bigger as the heat pump is running. When the
temperature of the evaporator gets too low, the automatic defrost control system will be
activated. This system 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.
4.5 Anti-frost Protection During Winter
This protection can only be activated if the heat pump is in STAND-BY mode.
4.5.1 First Anti-frost Protection
If the filter pump is controlled by the heat pump (regardless of the value for parameter 9),
when the water temperature is between 2 and 4°C and the air temperature is lower than
0°C, the filter pump will be automatically turned on to prevent the water from freezing in
the piping. This protection system will deactivate automatically when the temperature rises
again.
4.5.2 Second Anti-frost Protection
If the water temperature drops even more, that is, below 2°C (during long frost periods),
the heat pump will also start running to heat the water until its temperature reaches
3°C. When this minimum temperature is reached, the heat pump will stop, but anti-frost
protection will remain active until conditions change.
Summary of Contents for Power Smart SHP-100
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