Daikin R-410A Service Manual page 55

SiBE39-402A
3.2.2 Oil Return Operation in Heating Operation
[Conditions to start]
The heating oil-returning operation is started referring following conditions.
! Integrated amount of displaced oil
! Timer
Outdoor Unit Actuator
Compressor
Outdoor unit fan
Four way valve
Main electronic expansion valve
(EV1)
Subcooling electronic expansion
valve (EV2)
Hot gas bypass valve (SVP)
Receiver gas discharging valve
(SVG)
Ending conditions
* From the preparing oil-returning operation to the oil-returning operation, and from the oil-
returning operation to the operation after oil-returning, the compressor stops for 1 minute to
reduce noise on changing of the four way valve.
Fan
Electronic expansion valve
Function
(After the power is turned on, integrated operating-time is 2 hours and subsequently every 8
hours.)
In addition, integrated amount of displaced oil is derived from Tc, Te, and the compressor
load.
Oil return preparation
operation
Upper limit control
STEP8
ON
SH control
0 pls
OFF
ON
130 sec.
Indoor unit actuator
Thermostat ON unit
Stopping unit
Thermostat OFF unit
Thermostat ON unit
Stopping unit
Thermostat OFF unit
Oil return operation
124 Hz
OFF
OFF
1400 pls
0 pls
ON
ON
• 6 min.
or
• Ts - Te<5
Heating oil return operation
Special Control
Post-oil-return operation
2-step increase from
52 Hz to
(Pc - Pe>0.4 MPa) time
STEP8
ON
200~400 pls
0 pls
ON
OFF
• 160 sec.
or
• Pc - Pe>0.4MPa
OFF
OFF
OFF
500 pls
500 pls
500 pls
45