Mitsubishi Electric CITY MULTI PEFY-P20VMAL Technical & Service Manual page 22

[ VII Troubleshooting ]
Symptom
Valve closure fail-
ure (leaky valve)
Misconnections of
connectors or con-
tact failure
(4) Drain-up mechanism
Measure the resistance between the terminals with a tester.
(coil temperature 20°C)
1
3
(5) Drain float switch (CN4F)
Disconnect the connector, and measure the resistance between terminals with a tester.
(A)
1
2
3
4
Position of the moving part
Up
Down
HWE0812B
To check the LEV on the indoor unit, check the indoor unit liquid pipe temperature
that appears on the operation monitor on the outdoor unit's multi control board while
operating the indoor unit in question in the FAN mode and the other indoor units in
the cooling mode.
(A) Termistor (TH21)
(A)
LEV
Normally, the LEV is fully closed while the unit is in the FAN mode. If the valve is
leaky, liquid pipe thermistor reading will be lower than normal. If it is significantly
lower than the inlet temperature on the remote controller, valve closure failure is
suspected. If the amount of leakage is insignificant, replacement of LEV is unnec-
essary unless it is causing a problem.
Perform a visual check for disconnected connectors.
Perform a visual check of lead wire color.
Normal
340 Ω
(A)
(B)
(B)
(C)
(C)
(A)
Normal
Short
Open
Checking Criteria
Abnormal
Open or short
Moving part
Switch
Magnet
Abnormal
(any position but short)
(any position but open)
- 17 -
Remedy
Replace the LEV
if the amount of
leakage is great.
Disconnect the
connectors on
the control board
and perform a
continuity test.
GB