Fujitsu ASTG30KMTC - Auxiliary Heater Control by Outdoor Temp 1


Auxiliary heater control by outdoor temperature 1
This control selects heat pump or external heater according to the outdoor temperature. When out-
door temperature is high, the heating is performed by using heat pump only.
Operation Condition
Heater on Heater is on as shown in following diagram of heating temperature.
Heater off
• Heater is off as shown in following diagram of heating temperature.
•
Other than heating mode
• Error occurred
• Forced thermostat off
• Heat pump only zone
• Temperature of heater on (Thon): Adjustable by function number 62 (Operating temperature
switching of external heaters).
•
All control temperatures will shift by adjusting “Thon”.
• Outdoor temperature zone boundary A and B: Adjustable individually by function setting number
66 and 67.
• External heater output
Tr: Room temperature
Ts: Set temperature
Thon: Heater on temperature
Off
O
n
Tr-Ts ≥ 0.5°C
Tr-Ts
Tr-Ts (=Thon) ≤ -0.5°C
• Outdoor temperature zone
Heat pump only zone


(
Heat pump)
Combination zone


(Heat pump + Heater)
Heat pump prohibition zone


(Heater)
B: 6°C*
A: -20°C*
B + 2°C: 8°C
A + 2°C: -18°C
Outdoor temp.
*: Adjustable by function setting 66 and 67
3-4. Details of function - (05-28) - 3. External input and output (For indoor unit)
FIELD WORKING FIELD WORKING