Mitsubishi Electric PURY-P72TYJMU-A Service Handbook page 214

[ IX Troubleshooting ]
1. Error Code
2500
Drain sensor submergence (Models with a drain sensor)
2. Error definition and error detection method
1) If an immersion of the drain sensor in the water is detected while the unit is in any mode other than the Cool/Dry mode and
when the drain pump goes from OFF to ON, this condition is considered preliminary water leakage. While this error is being
detected, humidifier output cannot be turned on.(Applicable to the units manufactured in or after October 1996)
2) If the immersion of the sensor in the water is detected four consecutive times at an hour interval, this is considered water leak-
age, and "2500" appears on the monitor.
3) Detection of water leakage is also performed while the unit is stopped.
4) Preliminary water leakage is cancelled when the following conditions are met:
One hour after the preliminary water leakage was detected, it is not detected that the drain pump goes from OFF to ON.
The operation mode is changed to Cool/Dry.
Liquid pipe temperature - inlet temperature
3. Cause, check method and remedy
(1) Drain water drainage problem
ŒClogged drain pump
ŒClogged drain piping
ŒBackflow of drain water from other units
(2) Adhesion of water drops to the drain sensor
ŒTrickling of water along the lead wire
ŒRippling of drain water caused by filter clogging
(3) Failure of the relay circuit for the solenoid valve
(4) Indoor unit control board failure
ŒDrain sensor circuit failure
HWE0913A
-10°C[ -18°F]
Cause Check method and remedy
Check for proper drainage.
1) Check for proper lead wire installation.
2) Check for clogged filter.
Replace the relay.
If the above item checks out OK, replace the indoor unit
control board.
- 205 - GB