Pump Down (Refrigerant Collecting Operation); Compressor Preheating; Defrost Operation Control - Fujitsu AB*30LBAG series Service Instruction

5-15. PUMP DOWN ( Refrigerant collecting operation )
Perform the following procedures to collect the refrigerant when moving the indoor unit or the outdoor unit.
When the product is stopped:
1. Press the PUMP DOWN switch (SW2) on the outdoor unit.
(The LED on the outdoor unit circuit board flickers every 1second.)
2. The pump down operation (cooling operation) begins right away.
After operation starts, close the 3-way valve (liquid).
3. After 2-3minutes, operation stops. Close the 3-way valve (gas) within 1minute after operations stops.
4. The LED will go out 3minutes after it stops. Disconnect the power supply after confirming that the LED has gone out.
When the product is operating:
1. Press the PUMP DOWN switch (SW2) on the outdoor unit. The LED on the outdoor unit circuit board flickers
every 1second, and operation stops.
At this point, recovery has not been completed, so do not close the 2 and 3-way valves.
2. The pump down operation (cooling operation) begins after 3minutes.
Close the 3-way valve (liquid) after operation starts.
3. After 2-3minutes, operation stops. Close the 3-way valve (gas) within 1minute after operations stops.
4. The LED will go out 3minutes after it stops. Disconnect the power supply after confirming that the LED has gone out.

5-16. COMPRESSOR PREHEATING

When the outdoor heat exchanger temperature is lower than Operation temperature (Refer to Table 8) and the heating
operation has been stopped for 3 hours, power is applied to the compressor and the compressor is heated.
(By heating the compressor, warm air is quickly discharged when operation is started.)
When operation was started, and when the outdoor temperature rises to Release temperature or greater,
preheating is over.
(Table 8 : Preheating Operation / Release Temperature)
Before 24 hour
Operation Release
temperature temperature
3°C

5-17. DEFROST OPERATION CONTROL

1. CONDITION OF STARTING THE DEFROST OPERATION
The defrost operation starts when the outdoor heat exchanger temperature sensor detects
the temperature lower than the values shown in Table 9.
(Table 9 : Condition of starting Defrost Operation)
Compressor integrating
operation :Less than 45min.
AB*30LBAG
AB*36LBAG
AB*45LBAG
2. CONDITION OF THE DEFROST OPERATION COMPLETION
Defrost operation is released when the conditions become as shown in Table 10.
(Table 10 : Defrost Release Condition)
AB*30LBAG
AB*36LBAG
AB*45LBAG
After 24 hour
Operation
temperature
7°C 0°C
Less than 6 min. *1
Does not operate
Does not operate
*1. It means contiguous operation time.
*2. Compressor stop time: Below 20min.
Outdoor heat exchanger temperature sensor value is higher than 12°C or
Compressor operation time has passed 15 minutes.
Release
temperature
4°C
Compressor integrating
operation :45min and over
After 6 min. *1
or 10min. *2
or 10min. *2
°
-8 C *3
°
-10 C *4
°
-8 C *3
°
-10 C *4
Above 20min.
Release Condition
05-14
Outdoor temp. -
Outdoor heat exchanger
temp.
deg
12 C
*3. Outdoor temp. > -1°C
*4. Outdoor temp. < -1°C
Select 6min.
Select 10min.
Outdoor heat
exchanger temp.
°
-20 C
=