LG TCM 18 Service Manual page 16

9. Deice Control
• While in heating mode operation in order to protect the evaporator pipe of the outdoor unit from freezing, reversed to
cooling cycle to defrost the evaporator pipe of the outdoor unit.
• Defrost control is available 45 min. later since heating mode operation started, and it will not prolong over 10 min.
• Defrost control is carried out according to the following priority order while in heating mode operation.
1st priority : Defrost control is carried out according to the indoor pipe temp 60 min. later since heating mode opera-
tion started.
2nd priority : The temp differences between the indoor pipe temp and the intake air temp 25 min. later(∆T1) and 45
min. later (∆T2) since heating mode operation started are measured, then defrost control is carried out
according to the dirrerence (∆T=∆T1-∆T2)
3rd priority : Defrost control is carried out according to the temp difference (E=TE1-TE2) between the indoor pipe
temperatures of 25 min later(TE1) and 45 min later (TE2) after heating mode operation started.
• When the indoor pipe temp is 41°C or above, defrost control is not carried out even if the condition is one of the
defrost conditions above.
• While in defrost control, the compressor is on and the indoor fan, the outdoor fan, and the 4 way valve are off.
10. Soft Dry Operation
• During Soft Dry Operation, the compressor ON temperature is the setting temperature plus 1°C, the compressor
OFF temperature is the setting temperature minus 0.5°C.
• When the room temperature rises over the compressor ON temperature, the operation mode is switched to the
cooling mode.
• When the room temperature falls between the compressor ON temperature and OFF temperature, the operation
mode is switched to the Soft Dry Operation.
In this temperature range, 10min. Dry Operation, 7min operation OFF. During 10min Dry operation, if the room
temperature falls below compressor OFF temperature, Compressor OFF.
• In micom dehumidify mode, control of fan speed is as following.
Intake Air temp.
Setting temp. +1.0˚C
(Compressor ON)
Setting temp.
Setting temp. -0.5˚C
(Compressor OFF)
COMPRESSOR
OUTDOOR FAN
INDOOR FAN
2min.58sec. 10min.
Cooling
ON OFF ON
ON OFF ON
Selected
Fan
7min. 10min.
Within 7min. Cooling
OFF ON OFF
OFF ON OFF
Low Fan
–16–
2min.58sec.
ON OFF ON
ON OFF ON
Selected
Low Fan
Fan
OFF
OFF