Oil Return Control - Daikin SkyAir RZR-TA Series Service Manual

SiUS281811E
3.2

Oil Return Control

In order to prevent the compressor from running out of oil, oil return control is conducted to recover
oil that has flowed out from the compressor to the system side.
3.2.1 Oil Return Control in Cooling
HTdi : Compressor discharge pipe temperature (Tdi) compensated with outdoor air temperature
Pe : Low pressure sensor detection value
Tc: High pressure equivalent saturation temperature
Te: Low pressure equivalent saturation temperature
Ts1: Suction pipe temperature detected by thermistor R3T
Starting conditions
Referring to the set conditions for the following items, start oil return control in cooling.
 Cumulative oil feed rate
 Timer setting (Make this setting so as to start the oil return control when the initial cumulative
Furthermore, the cumulative oil feed rate is computed from Tc, Te, and compressor loads
Electric Symbol
Outdoor unit
18/24
actuator
class
Compressor M1C
Outdoor fan M1F
Main electronic Y1E
expansion valve
Subcooling —
electronic
expansion valve
Four way valve Y1S
Hot gas bypass Y2S
valve
Ending conditions
Fan
Electronic expansion valve
Part 4 Functions and Control
operating time reaches two hours after power supply is turned ON and then every eight hours.)
Oil return preparation
30/36/42/48
control
class
M1C Take the current step as
the upper limit.
M1F Fan control (Normal
M2F cooling)
Y1E 480 pulse (Fully open)
Y3E SH control
Y1S OFF
— OFF
20 seconds
Indoor unit actuator
Thermostat ON unit
Non-operating unit
Thermostat OFF unit
Thermostat ON unit
Non-operating unit
Thermostat OFF unit

Oil return control

Minimum frequency
(→ Low pressure
protection control)
Fan control (Normal
cooling)
480 pulse (Fully open)
0 pulse
OFF
OFF
x 3 minutes
OR
x Ts1 – Te < 5qC (9qF)
Cooling oil return control
Remote controller setting
Remote controller setting
Normal opening
224 pulse
Normal opening with forced thermostat ON
Special Control
Control after oil return
Same as oil return
control.
Fan control (Normal
cooling)
480 pulse (Fully open)
0 pulse
OFF
OFF
x 3 minutes
x Pe < 0.6 MPa (87 psi)
OR
x HTdi > 110°C (230°F)
OFF
81