Base Heater Operation ( For Aou36Rlxfzh ); Fresh Air Control ( For Au Type ); External Electrical Heater Control ( For Ar Type ) - Fujitsu ASU18RLF Service Instructions Manual

21. BASE HEATER OPERATION ( For AOU36RLXFZH )

The base heater is operated as shown in Fig. 18 .
( Fig. 18 : Base heater control )
When outdoor
temperature drops
OFF
36°F
(2°C)
ON
When the compressor stops, Base heater is OFF.
When the outdoor fan motor stops, Base heater is OFF.
In the cooling mode, Base heater is OFF.
In the defrost operation, Base heater maintains the same status as before the compressor stops.

22. FRESH AIR CONTROL ( For AU type )

The fan motor for Fresh Air is operated in synchronization with the indoor fan operation as shown in Fig. 19 .
( Fig. 19 : Fresh air control )
Operation
Fan motor
(Indoor unit)
Stop
Operation
Fan motor
(for Fresh Air)
Stop
*
It needs the external relay and power supply.

23. EXTERNAL ELECTRICAL HEATER CONTROL ( For AR type )

The External Electrical Heater is operated as below.
< Heater : O N condition >
When all of the following conditions are met, external elecrtical heater will operate according to Fig. 20 .
( Table 18 : External electrical heater control )
System type
Operation mode
Compressor
Indoor fan
< Heater : OFF condition >
1). When one of the ON conditions is not met.
2). When Defrost operation or Oil recovery operation starts
( Fig. 20 : External electrical heater control )
When the room
temperature drops
Ts -6°F(3°C)
Ts -22°F(12°C)
When outdoor
temperature rises
41°F
(5°C)
Heatpump
Heating
ON
ON (S-Lo is excluded)
When the room
temperature rises
Heater : OFF
Heater : ON
Heater : OFF
01-23
Ts : Setting temperature
Ts -2°F(1°C)
Ts -18°F(10°C)