THERMEx THW100, Руководство по эксплуатации продукта

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Heat Pump Manual
32
CONTROL
Water Flow Control
The system has a flow switch that monitors the flow. If the flow is interrupted for any reason
the controller shuts the unit down.
After the unit has reached temperature the pump will continue to run for 30 seconds
– this is
to flush the condenser once it has cooled down
If the flow is interrupted the unit will shut down. PUMP FAIL will display on the controller.
However the software will check every minute to see if the flow has returned. If the flow
switch has made again then the software will begin the start-up sequence again.
Compressor Hold Time
The controller will wait 120 before starting compressors up after shut down to prevent too
many start-ups.
Alarm Acknowledge Delay
This delay is the time that the program waits before flagging an alarm. It can be useful to
remove nuisance alarms that come up occasionally.
Multiple Unit Control
One heat pump will need to be assigned a master heat pump and the others slave heat
units
– see the service section for instructions on doing this. The master heat pump will do all
the controlling and timing.
When the master heat pump starts it will be the only one running to maintain the temperature
in the storage tanks. If however the water temperature drops below set point minus hysteresis
it will start the second heat pump and then monitor the change in temperature in the tank. If
the tank temperature is rising slower than the rate of change in the settings, it will start
another unit. If it is still dropping it will start another unit. If it is rising quickly it will take no
action. If the temperature is rising very slowly then all three units will all cut out together at the
set point.
Fan Control
The fans run at full speed all the time. After unit has reached temperature the fans will
continue to run for 30 seconds to boil off an excess refrigerant in the evaporators and prevent
freeze ups.
De-Icing Control
The units are equipped with hot gas solenoid valves which bleed hot gas into the evaporator.
This is controlled off pressure and will keep the coils free of ice at all times to ensure that the
unit runs at maximum efficiency at all time.
The controller monitors pressure and if the low pressure set point is triggered it open the
valve. The valve will stay open until either the pressure rises back above the low pressure set
point plus the LP pressure hysteresis OR the vales stays open to it time out which is 10 times
the compressor rest time
– default 20 minutes.
As soon as the valves closed when the pressures have returned to normal the software will
wait 5 seconds and start sampling the pressures again