Fujitsu General AOHG45KRTA, Service Manual, Page: 65 / 154

2-23. E: 99. 4-way valve error (Outdoor unit)
Indicator
Wired remote
controller
Error code E: 99
Detective actuator
Indoor unit main PCB When the indoor heat exchanger temperature is
compared with the room temperature, and either
following condition is detected continuously two times,
the compressor stops.
Indoor heat exchanger temp. - Room temp. > 10 °C
(Cooling or Dry operation)
Indoor heat exchanger temp. - Room temp. < -10 °C
(Heating operation)
If the same operation is repeated 5 times, the
compressor stops permanently.
Heat exchanger temperature
thermistor
Room temperature thermistor
4-way valve
Forecast of cause
Air filter clogged
Connector connection failure
Thermistor failure
Coil failure
4-way valve failure
Main PCB failure
Check point 1. Check air filter condition
Check air filter dirty.
→ If the air filter dirty, clean up the air filter.
↓
Check point 2. Check connection of connector
• Check if connector is removed.
• Check erroneous connection.
• Check if thermistor cable is open.
→ Upon correcting the removed connector or mis-wiring, reset the power.
↓
Check point 3. Check each thermistor
• Isn’t it fallen off the holder?
• Is there a cable pinched?
Check characteristics of room thermistor and indoor unit heat exchanger thermistor.
For the thermistor resistance value, refer to
"Thermistor resistance values" on page 03-52.
→ If defective, replace the thermistor.
↓
2-23. E: 99. 4-way valve error (Outdoor unit)
- (03-29) -
2. Troubleshooting with error code
TROUBLESHOOTING TROUBLESHOOTING