Blocked Valve In Cooling Mode - Mitsubishi PUMY-P60NKMU Technical & Service Manual

Check code
1501
Abnormal points and detection methods
Abnormal if stop valve is blocked during cooling operation.
Abnormal when both of the follwing temperature condition is satisfi ed for
20 minutes or more during coling condition.
1. TH22j − TH21j ] −2 °C [28.4 °F]
2. TH23j − TH21j ] −2 °C[28.4 °F]
Note:
For indoor unit, the abnormality is detected if an operating unit satisfi es the
condition.
●Diagnosis of defectives
Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards.
Is the outdoor liquid/gas valve fully
Disconnect the outdoor LEV wiring to
check the resistance.
Is there a resistance detected?
OCH502C

Blocked valve in cooling mode

Diagnosis
open?
Yes
No
v
Yes
Causes and check points
Outdoor liquid/gas valve is blocked.
Mulfunction of outdoor LEV (LEV1)(blockage)
TH21: Indoor intake temperature thermistor
TH22: Indoor liquid pipe tmperature thermistor
TH23: Indoor gas pipe tmperature thermistor
LEV: Linear expansion valve
No
Open the outdoor liquid/gas valve fully.
Replace the outdoor LEV.
Replace the outdoor controller board.
47
Remedy