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38MARB: Service Manual
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
21
DEFROST Mode
The air conditioning unit enters the
DEFROST
mode according to the
value of temperature of T3 and the value range of temperature change of
T3 plus the compressor running time (see Fig. 27).
During the
DEFROST
mode, the compressor keeps running however the
indoor and outdoor fan motors stop.
Forced DEFROSTING Mode:
1. Press and hold
AUTO/COOL
for 5s to enter the mode. The indoor fan
stops and the defrosting lamp illuminates. Use the remote control
to exit this mode and turn off the unit to stop the normal defrosting
mode.
2. To exit the
FORCED DEFROSTING
mode, press and hold
AUTO/
COOL
for 5s again.
Fig. 27 — Defrost Chart
Defrost Exit Conditions:
Any of the following conditions will cancel the
DEFROST
mode and change the unit to the normal
HEATING
mode:
NOTE:
T3 temperature refers to the sensor reading at the time when the
DEFROST
mode begins.
• T3 temperature rises above 59
F (15
C).
• T3 temperature remains above 46
F (8
C) for more than 80 seconds.
• The unit has been in the
DEFROST
mode for 10 minutes.
The indoor unit defrost lamp illuminates and the
logo appears.
Compressor run
Ɵ
me Temperature
Change
Condi
Ɵ
on 1
Total compressor running
Ɵ
me is 29 mins
T3-7
Ԩ
&
T30
-2.5
Ԩ
Condi
Ɵ
on 2
Total compressor running
Ɵ
me is 35 mins
T3 -5
Ԩ
&
T30
-3
Ԩ
Condi
Ɵ
on 3
Total compressor running
Ɵ
me is 40 mins
T3 -24
Ԩ
for 3 mins
Condi
Ɵ
on 4
Total compressor running
Ɵ
me is 120 mins
T3 -15
Ԩ
Condi
Ɵ
on 5
Total compressor running
Ɵ
me is 120 mins
T3 or T4
ч
-3
Ԩ