Mitsubishi Electric PUMY-P112VKM1 Service Manual page 68

Check code
2502
Abnormal points and detection methods
Drain pump (DP)
1Judge whether the sensor is in the water or in the air by turning the float
switch ON/OFF.
In the water: Detected that the float switch is ON for 15 seconds.
In the air: Detected that the float switch is OFF for 15 seconds.
2When the float switch remains to be turned ON for 3 minutes after
detected to be in the water, the drain pump is judged to be abnormal
and <2502> will be displayed.
Note:
It takes 3 minutes and 15 seconds to detect abnormality including the
time to judge to be in the water.
3The unit continue to detect abnormality while turned off.
4When the conditions below 1, 2 and forced outdoor unit stop condition
are met
1. Detected that
[liquid pipe temperature−room temperature] [ [ −10:] for 30 minutes
constantly.
2. Float switch detects to be in the water for 15 minutes constantly.
Note:
Before Forced outdoor unit stop condition is met, the unit always detects
1–3 above.
5The indoor unit detecting 4 above stops due to detecting abnormality
the outdoor unit in same refrigerant system compressor is inhibited to
operate). The unit which stops due to detecting abnormality displays
<2502>.
6Detection timing of forced outdoor unit stop
Constantly detected during unit operation and stop
7Releasing of forced outdoor unit stop
Reset power supply of both abnormal indoor unit and its outdoor unit in
same refrigerant system. Forced outdoor unit stop cannot be released by
remote controller OFF.
Note:
Above-mentioned 1–3 and 4–7 are detected independently.
●Diagnosis of defectives
Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards
Start cooling operation.
Does the drain pump work?
No
Continue to the next page
OCH576
Drain overflow protection
Diagnosis
Yes
Is the drain level unusually high?
No
<Float switch models>
Causes and check points
1 Malfunction of drain pump
2 Defective drain
Clogged drain pump
Clogged drain pipe
3 Defective moving part of float switch
Foreign matter on the moving
part of float switch (ex. sludge, etc.)
4 Defective float switch
5 Defective indoor controller board
Defective driving circuit of drain pump
Defective input circuit of float switch
6 Both of above mentioned 1 to 5 and the indoor linear
expansion valve full-closed failure (leakage)
happens synchronistically.
Note:
Address/Attribute displayed on the remote controller
shows the indoor unit which is the cause of trouble.
Check the drain discharge system for:
· Dirty drain pan (needs to be cleaned)
Yes
· Clogged drain pump
· Clogged or reverse connection of drain pipe
68
Chart 1 of 2
Remedy