[ VIII Troubleshooting ]
- 137 -
HWE1708A GB
2501
1. Error Code
Water pump fault
2. Error definition and error detection method
When clogged water circuit or water leaks from the water circuit is detected, the water pump is stopped for protection.
When the following statuses are detected, the pump will be stopped.
The revolutions of the water pump exceeds the specific range.
Pump discharge port: TH34, TH35 > 53ºC [127ºF]
3. Cause, check method and remedy
If a sudden water leak occurs, replace the water pressure protection valves because they may be the cause.
2501
Cause Check method and remedy
(1) Water circuit is clogged. 1) Check for tightened water flow rate control valves or field-
installed valves.
(2) Water leaks from the water circuit 2) Check the pump for proper sound.
If there is air in the circuit, it makes a noise.
(3) Air infiltration through the air vent valve 3) Check that any air vent valves are not installed in the water
circuit on the suction side water pump.
If an air vent valve is installed in the water circuit on the suc-
tion side water pump, it will cause the air infiltration.
(4) Broken or semi-broken thermistor wire 4) Check for a broken thermistor wire.
(5) Thermistor failure 5) Check the resistance of the thermistor.
0°C [32°F] : 6.0kΩ
10°C [50°F] : 3.9kΩ
20°C [68°F]: 2.6kΩ
30°C [86°F] : 1.8kΩ
40°C [104°F] : 1.3kΩ
(6) Semi-broken pump wire 6) Check for semi-broken pump wires.
0000002394.book 137 ページ 2023年9月7日 木曜日 午後4時2分