Fujitsu air conditioner troubleshooting

In the following situations stop operation immediately and get in touch with authorized service personnel.

The problem cannot be solved even when the troubleshooting checks have been performed.

The OPERATION indicator lamp (red) is flashing very fast (when receiver unit is connected).
The wired remote controller or simple remote controller indicate EE (when connected).
It has burning smell

Fujitsu ABT series

 SymptomProblem
NORMAL FUNCTIONDoesn't operate immediately:- If the unit is stopped and then immediately started again, the compressor will not operate for about 3 minutes, in order to prevent fuse blowouts.
- Whenever the power supply plug is disconnected and then reconnected to a power outlet, the protection circuit will operate for about 3 minutes, preventing unit operation during that period.
Noise is heard:- During operation and immediately after stopping the unit, the sound of water flowing in the air conditioner's piping may be heard. Also, noise may be particularly noticeable for about 2 to 3 minutes after starting operation (sound of coolant flowing).
- During operation, a slight squeaking sound may be heard. This is the result of minute expansion and contraction of the front cover due to temperature changes
- During Heating operation, a sizzling sound may be heard occasionally. This sound is produced by the Automatic Defrosting operation.
Smells:- Some smell may be emitted from the indoor unit. This smell is the result of room smells (furniture, tobacco, etc.) which have been taken into the air conditioner.
Mist or steam are emitted:- During Cooling or Dry operation, a thin mist may be seen emitted from the indoor unit. This results from the sudden Cooling of room air by the air emitted from the air conditioner, resulting in condensation and misting.
- During Heating operation, the outdoor unit's fan may stop, and steam may be seen rising from the unit. This is due to the Automatic Defrosting operation.
Airflow is weak or stops:- When Heating operation is started, fan speed is temporarily very low, to allow internal parts to warm up.
- During Heating operation, if the room temperature rises above the thermostat setting, the outdoor unit will stop, and the indoor unit will operate at very low fan speed. If you wish to warm the room further, set the thermostat to a higher setting.
- During Heating operation, the unit will temporarily stop operation (between 7 and 15 minutes) as the Automatic Defrosting mode operates. During the Automatic Defrosting operation, the OPERATION indicator lamp will flash
- The fan may operate at very low speed during Dry operation or when the unit is monitoring the room's temperature
- In case of Multi-type unit, if multiple units are operated in different operation modes as shown below, the units operated afterward will stop and "start" will be shown on the remote controller display of the stopped indoor units.
Heating mode and cooling mode (or dry mode)
Heating mode and fan mode
- During QUIET operation, the fan will operate at very low speed
- In the monitor AUTO operation, the fan will operate at very low speed.
Water is produced from the outdoor unit:- During Heating operation, water may be produced from the outdoor unit due to the Automatic Defrosting operation
The FILTER lamp blinks:- Clean the filter. Afterwards, turn the FILTER lamp off.
CHECK ONCE MOREDoesn't operate at all:- Has the circuit breaker been turned off?
- Has there been a power failure?
- Has a fuse blown out, or a circuit breaker been tripped?
- Is the timer operating?
Poor Cooling (or *Heating) performance:- Is the air filter dirty?
- Are the air conditioner's intake grille or outlet port blocked?
- Did you adjust the room temperature settings (thermostat) correctly?
- Is there a window or door open?
- In the case of Cooling operation, is a window allowing bright sunlight to enter? (Close the curtains.)
- In the case of Cooling operation, are there heating apparatus and computers inside the room, or are there too many people in the room?
- Is the unit set for QUIET operation?
The unit operates differently from the remote control unit's setting:- Are the remote control unit's batteries dead?
- Are the remote control unit's batteries loaded properly?
Signal is not received after replacing the batteries for the remote control unit:Are you using an air conditioner signal code other than signal code A?

Fujitsu air conditioner troubleshooting

SymptomProblem
Doesn't operate immediately:- If the unit is stopped and then immediately started again, the compressor will not operate for about 3 minutes, in order to prevent fuse blowouts.
- Whenever the electrical breaker is turned off then on again, the protection circuit will operate for about 3 minutes, preventing unit operation during that period
Airflow is weak or stops:- When Heating operation is started, indoor unit's fan may temporarily stop, to allow internal parts to warm up.
- During Heating operation, if the room temperature rises above the thermostat setting, the outdoor unit will stop, and the indoor unit's fan will stop. If you wish to warm the room further, set the thermostat for a higher setting.
- During oil recovery operation, the air flow may stop for approximately 10 minutes.
- During Heating operation, the unit will temporarily stop operation (between 4 and 15 minutes) as the Automatic Defrosting mode operates.
- The fan may operate at low speed during Dry operation or when the unit is monitoring the room's temperature.
- In the monitor AUTO operation, the fan will operate at low speed.
Flashing lamps: (limited to only when receiver unit is connected)The OPERATION indicator lamp (red) flashes: An oil recovery operation is being performed
The OPERATION indicator lamp (red) flashes: An automatic defrosting operation is being performed
The OPERATION indicator lamp (red) and TIMER indicator lamp (green) are flashing alternately: It has recovered from a power outage.
The OPERATION indicator lamp (red) and TIMER indicator lamp (green) are flashing simultaneously:
It is operating in trial operation mode.
Ask a manager as there may be maintenance being conducted.
The OPERATION indicator lamp (red) lights up and the TIMER indicator lamp (green) flashes: This is the standby state.
Noise is heard:- In the following conditions there are sounds of water flowing from the indoor unit and the operation sound becomes loud. These are the sounds of the flowing of refrigerant.
When operation starts
When oil recovery operation finishes
When automatic defrosting operation finishes
- During operation, a slight squeaking sound may be heard. This is the result of minute expansion and contraction of the panel due to temperature changes.
- During Heating operation, a sizzling sound may be heard occasionally. This sound is produced by the Automatic Defrosting operation.
Smells:Some smell may be emitted from the indoor unit. This smell is the result of room smells (furniture, tobacco, etc.) which have been taken into the air conditioner.
Fog comes out of the indoor unit:During Cooling operation, a thin mist may be seen emitted from the indoor unit.
This results from the sudden Cooling of room air by the air emitted from the air conditioner, resulting in condensation and misting.
Steam comes out of the indoor unit:During Heating operation, the outdoor unit's fan may stop, and steam may be seen rising from the unit. This is due to the Automatic Defrosting operation.
Water is produced from the outdoor unit:During Heating operation, water may be produced from the outdoor unit due to the Automatic Defrosting operation
Doesn't operate at all:- Has there been a power failure?
- Has a fuse blown out, or a circuit breaker been tripped?
- Is the main power switch set to the OFF position?
- Are you trying to engage in an operation different from the priority state?
- Is it in standby state?
The operation mode cannot be changed:Are you trying to change to an operation different from the priority conditions?
Poor Cooling (or Heating) performance:- Did you adjust the room temperature settings (thermostat) correctly?
- Is the air filter dirty?
- Are the air conditioner's inlet port or outlet port blocked?
- Is there a window or door open?
- In the case of Cooling operation, is a window allowing bright sunlight to enter? (Close the curtains.)
- In the case of Cooling operation, are there heating apparatus and computers inside the room, or are there too many people in the room?
- Is the fan speed set to low?

OPERATING TIPS

Microcomputer-controlled automatic defrosting

When using the Heating mode under conditions of low outdoor air temperature high humidity, frost may form on the outdoor unit, resulting in reduced operating performance. In order to prevent this kind of reduced performance, this unit is equipped with a Microcomputer-controlled automatic defrosting function. If frost forms, the air conditioner will temporarily stop, and the defrosting circuit will operate briefly (for about 4 to 15 minutes).

During Automatic Defrosting operation, the OPERATION indicator lamp (red) will flash (limited to only when receiver unit is connected)

Oil recovery operation

Periodically, the oil recovery operation is performed in order to return compressor oil to the outdoor unit.

During oil recovery operation, the OPERATION indicator lamp (red) will flash (for about 10 minutes) (limited to only when receiver unit is connected).

If the air conditioner is used under higher temperature conditioner than those listed, the built-in protection circuit may operate to prevent internal circuit damage. Also, during Cooling and Dry modes, if the unit is used under conditions of lower temperature than those listed above, the heat-exchanger may freeze, leading to water leakage and other damage.

G If the unit is used for long periods under high-humidity conditions, condensation may form on the surface of the indoor unit, and drip onto the floor or other objects underneath.

G Do not use this unit for any purposes other than the Cooling, Heating, Dehumidifying, and air-circulation of rooms in ordinary dwellings.

Cleaning the air filter

Remove dust with a vacuum cleaner or by washing. After washing, be sure to allow it to dry thoroughly in a shady place before reinstalling.