Pump-Down Residual Operation - Daikin ALTHERMA HT ERSQ 011 AA Service Manual

Special Control

3.3 Pump-down Residual Operation

When activating compressor, if the liquid refrigerant remains in the heat-exchanger, the liquid enters into
the compressor and dilutes oil therein resulting in decrease of lubricity.
Therefore, the pump-down residual operation is performed to collect the refrigerant in the heat-exchanger
when the compressor is down.
3.3.1 Pump-down Residual Operation in Heating Operation [R-410A]
Actuator
Compressor
Outdoor unit fan
Four way valve
Main electronic expansion valve (EV1)
Subcooling electronic expansion valve
(EV3)
Hot gas bypass valve (SVP)
Ending conditions
60

Pump-down residual operation

124 Hz Full load
STEP7
ON
0 pls
0 pls
OFF
4 sec.
ESIE09-08A
Function