Service manual

2-13
2.5.3 Defrosting mode
Start defrosting
Is terminating
condition OK?
●Defrost lamp (red) ON
●Pump down
Defrosting range
Defrosting lamp (red) OFF
Return to frozen, chilled or partial
frozen operation
Evaporator fan On after delay of 60 seconds
●Compressor ON
●Evaporator fan OFF
●Condenser fan ON/OFF
●
Defrosting solenoid valve ON
●
Hot gas solenoid valve ON
No
Yes
Yes
Component name Pump down Defrosting
Compressor CC ON ON
Evaporator fan. High speed EFH
ON/OFF※3 OFF
Evaporator fan. Low speed EFL
Condenser fan CF
ON/OFF※1 ON/OFF※1
Liquid solenoid valve LSV OFF OFF
Economizer solenoid valve ESV ON/OFF※4 OFF
Injection solenoid valve ISV
OFF (ON※5) ON/OFF※2
Hot-gas solenoid valve HSV OFF ON
Defrost solenoid valve DSV OFF ON
Discharge gas by-pass solenoid valve BSV OFF OFF
Reheat solenoid valve RSV OFF OFF(ON ※ 6)
Suction modulating valve SMV 100% 100%
Electronic expansion valve EV 10 to 100% 5%
Operation of magnetic contactor and solenoid valve
Note) ※1: Pressure control
※2: Charging control
※3: Frozen mode ... EFL ON, Chilled mode ... EFH ON
※4: Economizer control
※5: Discharge gas temperature control
※6: EOS>15˚C
Magnetic
contactor
Solenoid valve