Oil Return Operation - Daikin ERQ Service Manual

ESIE09-05
3.2

Oil Return Operation

In order to prevent the compressor from running out of oil, the oil return operation is conducted to recover oil flown out
from the compressor to the system side.
3.2.1 Oil Return Operation in Cooling Operation
[Start conditions]
Referring to the set conditions for the following items, start the oil return operation in cooling.
• Cumulative oil feed rate
• Timer setting (Make this setting so as to start the oil return operation when the initial cumulative operating time
reaches two hours after power supply is turned ON and then every eight hours.)
Furthermore, the cumulative oil feed rate is computed from Tc, Te, and compressor loads.
Outdoor unit 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
Fan
Function
Oil return preparation
operation
Take the current step as the
upper limit.
Fan control (Normal cooling) Fan control (Normal cooling) Fan control (Normal cooling)
OFF
480 pls
SH control
OFF
20 sec.
AHU actuator
Thermostat ON unit
Stopping unit

Oil return operation

52 Hz Full load
(→ Low pressure constant
control)
OFF
480 pls
0 pls
OFF
• 3 min.
or
• Ts - Te<5° C
Cooling oil return operation
: http://splitoff.ru/tehn-doc.html
Special Control
Post-oil-return operation
"
Same as the oil return
"
operation mode.
OFF
480 pls
0 pls
OFF
• 3 min.
• Pe<0.6MPa
• HTdi>110° C
ON
OFF
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