External Electrical Heater Control; Electronic Expansion Valve Control - Fujitsu ACUH09LUAS1 Service Manual

7-6. External electrical heater control

The external electrical heater is operated as below.
Ts -5.4°F
(Ts -3°C)
Ts -21.6°F
(Ts -12°C)
NOTES:
• →hen the compressor stop, external electric heater is off.
• It operates only in heating mode and when the indoor fan operates. (However, S-LO→ is exclud-
ed.)

7-7. 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
Cooling/dry mode
Heating mode
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).
7-6. External electrical heater control
Heater : Off
Heater : On
Heater : Off
When the room
temperature drops
When the room
temperature rises
Ts -1.8°F
(Ts -1°C)
Ts -18.0°F
(Ts -10°C)
Between 52 and 480 pulses
- (04-27) -
Ts: Setting temperature
Pulse range
7. Various control