“A5” Freeze-Up Protection Control Or High Pressure Control - Daikin Altherma EKHBH Series Service Manual

ESIE06-03
"A5" Freeze-up Protection Control or High Pressure Control
2.3
A5
Error code
Method of
malfunction
detection
Malfunction
decision conditions
Supposed causes
Troubleshooting
See also "Check No.06" on page 3-53.
Caution Be sure to turn off power switch before connect or disconnect connector, or parts damage may be
occurred.
Part 3 – Troubleshooting
High pressure control (heat pump model only)
During heating operations, the temperature detected by the hydro-box heat exchanger thermistor
is used for the high pressure control (stop, outdoor fan stop, etc.)
The freeze-up protection control (operation halt) is activated during cooling operation according to
the temperature detected by the hydro-box heat exchanger thermistor.
High pressure control
During heating operations, the temperature detected by the hydro-box heat exchanger thermistor
is above 65°C
Freeze-up protection
When the hydro-box heat exchanger temperature is below 0°C during cooling operation.
Detection error due to faulty hydro-box heat exchanger thermistor.
Detection error due to faulty hydro-box PCB.
Check No. 06
Hydro-box heat exchanger
thermistor check
Does it
conform to the thermistor
characteristic
chart?
NO
YES
Error Codes: Hydro-box
Replace the hydro-box PCB.
Replace the thermistor (replace the
hydro-box PCB).
1
3
4
5
3–9