Defrost Control - LG Single A Svc Manual

7. Defrost Control

7.1 Function
:These are about the control of compressor, fan of outdoor unit, reversing valve, LEV.
7.2 Starting to the defrosting operation
A) Defrost operation will be start when all the conditions below are matched simultaneously
Accumulation time of operation and the period after completion of defrost = 35min (Outdoor air temperature –3˚C)
B) Outdoor piping temperature is below than –6 (Option)˚C for starting defrosting operation.
7.3 Completion of defrost operation
Send signal of defrost completion in case of meeting one of the condition as below.
1. Defrosting time £æ 7 minutes
2. Piping temperature maintain 10 seconds (Option ) in condition of more than 15˚C (Option).
7.4 Defrosting Control Algorithm
Control
Inverter Comp.
Control
Outdoor LEV
ON
Reversing Valve
Indoor Fan
ON
Outdoor Fan
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Only for training and service purposes
Satisfy
Defrost
Defrost
Start
Start
Condition
1 2 3
350 Pulse
Defrost signal of
indoor unit on/
Starting maximum defrosting
time count
Satisfy
Defrost
End
Condition
4 5 6
(Option)
80 Hz
(Option)
Indoor defrost signal OFF
OFF
OFF
OFF
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Part 3 Control logic
Heating
Start
(Defrost flag clear)
7 8 9
ON
Hot
start
ON/OFF
LGE Internal Use Only
10
Baseline