Pressure Equalization Prior To Startup - Daikin SkyAir RZR-P Series Service Manual

Special Control
3.7

Pressure Equalization Prior to Startup

Ta: Outdoor air temperature
Pc: High-pressure sensor detection value
Pe: Low-pressure sensor detection value
Before activating the compressor, the activation load is lightened by equalization across the
compressor. In addition, inverters turn ON electricity and capacitors are charged.
Parts Name Symbol
Compressor

(INV.)
Outdoor unit

fan
Four-way
20S1
valve
Electronic
expansion EV1
valve (Main)
Solenoid valve
SVP
(Hot gas)
Solenoid valve
(Receiver gas SVG
discharging)
Ending conditions
Function and Control
Electric Symbol
RZR18/24/32P RZR36/42P
RZQ18/24/30P RZQ36/42P
M1C M1C
M1F
M1F
M2F
Y1S Y1S
Y1E Y1E
Y2S Y2S

Y3S
Operation
OFF
Cooling: OFF
Heating: Ta > 78.8°F; STEP 8,
Ta 78.8°F; OFF
Keep former condition.
0 pls
ON
OFF
 3 minutes
OR
 Pc – Pe < 29 psi
SiUS281117
Remarks







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