HISEER AS10S/L, Operation Installation Maintenance Manual

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9
Buffer Tank
A buffer tank is recommended to ensure a trouble free heat pump operation. A suitable
buffer tank can avoid excessive heat pump cycling (switching on and off).
The buffer tank provides a hydraulic separation from the volume flow in the heat
pump and heating circuits. The volume flow in the heat pump circuit remains constant,
even if the heating circuit volume flow is reduced by thermostatic valves.
If the total of the systems water volume is less than 12L/KW then a buffer tank should
be added to reduce the compressor from ON/OFF cycling. This will prolong the
compressor life span.
When a buffer tank is installed, the heating system will absorb energy from the buffer
tank first. To save energy consumption ,install the indoor pump P1 that is switched on
only when compressor is on. This is by changing EV01 indoor pump mode to “work
by regulation”.
Inlet water temp sensor should be taken out of the unit and put into buffer tank’s
sensor pocket. The Inlet water temp sensor is located on inlet water pipe. The Inlet
water temperature sensor B1 in the buffer tank will control the tank temperature by
starting and stopping the compressor and pump together as required.
If Inlet water temp sensor has not been changed to buffer tank’s sensor pocket when
EV01 has been changed to “work by regulation”, when the unit reaches its set
temperature ,the compressor will stop, pump P1 will also stop accordingly due to
EV01 being set to “work by regulation”. When this occurs ,there is no water
circulation between the heat pump and buffer tank. Inlet water temp will keep its
stopped temperature ,not the buffer tank water temperature. Inlet water temp sensor
B1 then can not switch on compressor and pump P1 even when buffer tank water is
getting cold. Changing the Inlet water temp sensor into the buffer tank will avoid this
problem.
Buffer Tank