Mitsubishi Electric MSZ-G09SV-E1 Service Manual page 30

(3) Warm air control.
When the following any condition of 1 (a. ~ d.) and the condition of 2 are satisfied at the same time, warm air control
works.
1 a.) when the operation mode has been changed to HEAT mode
b.) when cold air prevention has been released
c.) when defrosting has been finished
d.) when the compressor starts in HEAT mode
2 When the temperature of indoor coil thermistor RT12 is less than 37°C.
When warm air control works, the fan speed changes as follows to blow out warm air gradually.
Gradation of fan speed in initial
The upper limit of the fan speed in MANUAL is the set speed.
The upper limit of the fan speed in AUTO is the speed decided by indoor fan speed control.
When the temperature of RT12 has been 37°C or more, or when the set speed has been changed, this control is
released and the fan speed is the set speed.
(4) Flow soft control
When the thermostat (compressor) is off, the indoor fan operates as follows.
Compressor
OFF
ON
2. High pressure protection
In HEAT mode the indoor coil thermistor detects the temperature at the indoor heat exchanger and controls the compressor
operational frequency to prevent the condensing pressure from increasing excessively.
3. Overload starting
When the room temperature thermistor reads 18°C or above, the compressor runs with its maximum frequency regulated for
3 minutes after the start-up.
4. Defrosting
(1) Starting conditions of defrosting
When the following three conditions, a), b), and c), are satisfied, the defrosting starts.
a) The defrost thermistor reads -3°C or below.
b) The cumulative operation time of the compressor has reached any of the set values: 35, 40, 45, 50, 55, 60, 65, 70,
75, 80, 85, 90, 95, 100, 105 minutes.
c) More than 5 minutes have passed since the start-up of the compressor.
w Set value of compressor operation time(hereinafter referred to as defrost interval)
The first defrost interval is 32 minutes long, and the second 35 minutes long.The third and subsequent intervals are
set to be longer, and less frequent, depending on defrosting time.
The third and subsequent defrost intervals follow any of the three patterns ... 5 or 10 minutes longer, the same, or 5 or
10 minutes shorter compared with the previous defrost interval ... with the longest 115 minutes and the shortest 30
minutes.
(2) Releasing conditions of defrosting
Defrosting is released when any of the following condition is satisfied:
a) The defrost thermistor reads 13°C or above.
b) Defrosting time has exceeded 10 minutes.
c) Some other modes than HEAT mode is set during defrosting.
<Time condition>
less than 2 minutes
2 minutes to 4 minutes
more than 4 minutes
Fan
Very Low
Set speed
<Indoor fan speed>
Low
Med.
High
NOTE : When the thermostat(compressor) turns on, the fan will operate
at set speed. But until cold air prevention and warm air control
is released, the fan speed follow them.
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