HISEER AS10S/L, Operation Installation Maintenance Manual

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The pump PWM running control (Y3)
On cooling mode, when compressor is on, pump PWM runs as EV05 for 3 minutes, then runs
with
（ Inlet temperature-Outlet temperature ） =EV03 as target via PID control . when compressor
is off, pump PWM runs as EV06.
On heating mode, when compressor is on, pump PWM runs as EV05 for 3 minutes, then runs with
（ outlet temperature - Inlet temperature ） =EV04 as target via PID control ； when compressor is off,
pump PWM runs as EV06.
On DHW mode, pump PWM runs as EV05. After DHW temperature reaches preset temperature,
if the unit does not need to do cooling or heating, pump PWM is off.
pump PWM runs as EV05 on defrosting.
As other situation, when pump is on, PWM is EV06, PWM is off when pump is off.
Pump PWM will starts running for 3 minutes when pump is off for 24 hours to avoid seizure
Defrosting control
The unit is equipped with hot gas defrosting. When the conditions of defrosting starting are met,
the fan stops, the 4 way valve changes direction and the hot gas flows out to the finned coil heat
exchanger instead. After the condition of defrosting exit is met, the fan starts, the hot gas flows
into brazed plate heat exchanger and the unit returns to normal operation.
Defrosting starting conditions (all must be met)
Ambient temperature B3
＜ DF03
The unit running time after previous defrosting
＞
DF06
Ambient temp. B3 minus LPS B11 ＞ DF04, last DF05 time
LPS B11
≤DF12；
Defrosting exit condition ( any of the following condition is met)
HPS B12
≥ DF09 ,last 10 seconds.
Defrost time ≥ DF10
Temperature sensor B1, B2,B6 ,B11 or B12 trouble.
Service Guide