ESIE13-02
Error Codes: Hydro-box
95
Part 4 – Troubleshooting
4
3
4
5
4
3.2
“89”
Water Heat Exchanger Frozen
User interface
display
89
Method of
malfunction
detection
The freeze-up protection control (operation halt) is activated during cooling operation according to the
temperature detected by the hydro-box heat exchanger thermistor.
Malfunction
decision conditions
Freeze-up protection:
When the hydro-box heat exchanger temperature is below 0°C during cooling operation.
Supposed causes
Detection error due to faulty hydro-box heat exchanger thermistor.
Detection error due to faulty hydro-box PCB.
Troubleshooting
See also "Check No.4 - Resistance Conversion Table (Ambient, Coil, Fin)" on page 153.
Caution
Be sure to turn off power switch before connecting or disconnecting connector, otherwise parts may
be damaged.
Check No. 04
Hydro-box heat exchanger
thermistor check
YES
Is it
conform to the thermistor
characteristic
chart?
NO
Replace the hydro-box PCB.
Replace the thermistor (replace the
hydro-box PCB).
