Daikin R407C PLUS - Oil Return;Defrost Operation

Outline of Control (Outdoor Unit) < Symbols using in this manual > Si33-105
84 Function R407C PLUS Series Heat Recovery System
3.6 Oil Return/Defrost Operation
3.6.1 Oil Return Operation
Activates the oil return operation to collect refrigerant oil from the field pipes when the following
conditions are met.
[Start conditions]
1. When cumulative compressor operating time from power ON exceeds 2 hours
2. When cumulative compressor operating time from completion of previous return operation
exceeds 8 hours.
However, when the upper-limit frequency is limited to less than “A” Hz during the previous oil
return operation, the above time period of 8 hours is changed to 4 hours.
The oil return operation is activated every 1 hour during 3.6.5 “Cooling overload control”.
"
1)When defrost control operation for more than 4 minutes with inverter compressor frequency
of “A” Hz or higher, oil return time reset to 8 hours.
2) When condition 1. or 2. is satisfied during heating operation, the electric heaters of indoor
units are turned off 2 minutes prior in order to prepare for the oil return operation.
3) The oil return operation is not activated for 28 minutes after the completion of the previous
defrosting operation.
4) When Th7-Te<10 (30 seconds or more) during defrosting operation, oil return timer is reset.
5) The oil return operation is not activated during DSHi<20 and for 10 minutes after going out of
DSHi<20. (The oil return operation is activated after the cancellation of this condition.)
6) When the compressor operation sequence comes to the oil return operation during startup
control, the oil return operation is activated from the preparation after the completion of
startup control.
[Oil return operation]
!
The oil return operation is shown on following pages.
[Ending conditions]
!
The oil return operation ends after 4 minutes of operation. However, when the compressor
stop conditions are met during an oil return operation, the compressor stops after the
completion of the oil return operation.
When the compressor stops during an oil return preparation operation, the oil return
operation is activated at the next startup.
[Compressor frequency during oil return operation]
HP
Oil return operation
ABCDE
INV
STD1 STD2
INV
STD1 STD2
INV
STD1 STD2
INV INV
STD1
16HP 71Hz OFF — 52Hz OFF — 52Hz ON — 64Hz 41Hz ON —
18HP 71Hz OFF — 52Hz OFF — 71HZ ON — 64Hz 64Hz ON —
20HP 71Hz OFF — 52Hz OFF — 71Hz ON — 64Hz 64Hz ON —
24HP 52Hz ON OFF 41Hz ON OFF 52Hz ON ON 64Hz 41HZ ON ON
26HP 52Hz ON OFF 41Hz ON OFF 52Hz ON ON 64HZ 41Hz ON ON
28HP 52Hz ON OFF 41Hz ON OFF 52Hz ON ON 64HZ 41Hz ON ON
30HP 52Hz ON OFF 41Hz ON OFF 52Hz ON ON 64HZ 41Hz ON ON