Special Operation - Fujitsu AUXB04GALH Service Manual

2-5 SPECIAL OPERATION

2-5-1 Oil Recovery Operation
Purpose of the operation
The amount of refrigerant lubricant oil which has been transported to the indoor units
and the connection pipe with the refrigerant will become large as the operation time of compressor increases.
It is necessary to recover the oil back into the outdoor unit for a certain time interval
in order to prevent compressors from damaging due to lack of lubrication oil.
1. Oil Recovery in Cooling operation
<
Start condition >
Compressor accumulated operation time since last cooling oil recovery operation exceeds 3 hours (first time : 1hour)
< End condition >
30 seconds have elapsed since the start and "suction temperature - low pressure saturation temperature
have elapsed since the start.
< Operation >
COMPRESSOR: The rotation speed varies depending on the operation state.
EEV Opening (Indoor/Outdoor unit): Controlled pulse (as normal operation mode).
FAN speed (Indoor/Outdoor unit)
2. Oil Recovery in Cooling start-up operation
<
Start condition >
LP < 0.13Mpa
< End condition >
HP- LP 0.7Mpa and LP
< Operation >
COMPRESSOR: The rotation speed varies depending on the operation state.
EEV Opening (Indoor/Outdoor unit): Controlled pulse (as normal operation mode).
FAN speed (Indoor/Outdoor unit)
3. Oil Recovery in Heating operation
< Start condition >
Compressor accumulated operation time since the last heating oil recovery exceeds 8 hours (first time : 1hour)
< End condition >
After 4 minutes have elapsed
< Operation >
COMPRESSOR: The rotation speed varies depending on the operation state.
EEV Opening (Indoor/Outdoor unit) : Controlled pulse (as normal operation mode)
FAN speed (Indoor/Outdoor unit)
Others
During the oil recovery operation,
and appears on the simple remote controller.
The operation indicators (LED) of the indoor units flash slowly.
: Controlled fan speed (as normal operation mode).
0.18Mpa or LP 0.52Mpa or 15 minutes have elapsed since the start.
: Controlled fan speed (as normal operation mode).
: Controlled fan speed (as normal operation mode)
appears on the display of wired and central remote controller,
02-08
5deg" or 6 minutes