Fujitsu AOTG30KMTC, Service Manual, Page: 154 / 199

7-8. Compressor preheating
By preheating the compressor, warm airflow is quickly discharged when the operation is started.
• Triggering condition 1
– Outdoor temperature ≤ 20°C
When outdoor temperature reaches following degrees, compressor preheating stops.
30 model 25°C
34 model 26°C
– 30 minutes after compressor stopped
• Triggering condition 2
0°C
Off
On
Tn
Tn
2°C
Tn: Outdoor unit heat exchanger temp.
7-9. Electronic expansion valve control
The most proper opening of the electronic expansion valve is calculated and controlled under the
present operating condition based on the table below.
Operation mode Pulse range
Cooling/dry mode Between 32 and 480 pulses
Heating mode Between 45 and 480 pulses
NOTE: At the time of supplying the power to the outdoor unit, the initialization of the electronic ex-
pansion valve is operated (528 pulses are input to the closing direction).
7-10. Prevention to restart for 3 minutes (3 minutes st)
Compressor won’t enter operation status for 140 seconds after compressor is stopped, even if any
operation is given.
7-8. Compressor preheating
- (04-22) -
7. Various control
CONTROL AND FUNCTIONS CONTROL AND FUNCTIONS