Check Of Lev (Expansion Valve); Check Of Outdoor Thermistor - Mitsubishi Electric Mr.Slim MSH24WN Service Manual

When OPERATION INDICATOR lamp flashes 10-time. Heating/ Cooling doesn't operate.

Check of LEV (Expansion valve)

H
1 During pressing the OPERATION SELECT button
and the TOO COOL button on the remote controller,
press the RESET button.
2 First, release the RESET button.
(After 3 seconds, confirm all displays of the remote
controller.)
3 Then release the OPERATION SELECT button.
With remote controller set toward the indoor unit, press
the OPERATE/ STOP(ON/ OFF) button and confirm one
beep tone.
LEV operates in full-opening
direction.
Do you hear LEV "click,
click·······"?
Do you touch LEV and feel
it vibrate?
No
Is LEV coil properly fixed to
the body?
Yes
Does the resistance of LEV coil
have the characterictics?
No
Replace the
LEV coil.
When OPERATION INDICATOR lamp flashes 6-time. Thermistors in the outdoor unit are abnormal.

Check of outdoor thermistor

I
w Disconnect the connectors CN661 and/ or CN662 from the deicer P.C. board.
(Check the characteristics of each thermistor.)
Defrost thermistor(RT61)
Measure
resistance
between CN 661
1 and 2.
Discharge temperature
thermistor(RT62)
Measure
resistance
Turn OFF the
between CN 662
power supply.
1 and 2.
Ambient temperature
thermistor(RT63)
Measure
resistance
between CN 662
3 and 4.
Yes
Ok
No
Properly fix LEV coil to
the body.
Yes
Replace the
deicer P.C. board.
Does the resistancs
of thermistor have
the characteristics
on page 42?
No
Replace the
thermistor.
1 During pressing the OPERATION SELECT
button and the TOO COOL button on the
remote the controller, press the RESET button.
2 First, release the RESET button.
(After 3 seconds, confirm all displays of the
3 Then release the OPERATION SELECT button.
˚F
CLOCK
AMPM
AMPM
Characteristics of LEV coil
LEV (CN724)
WHT–RED
RED–ORN
YLW–BRN
BRN–BLU
NOTE : After check of LEV, do the undermentioned operations.
1. Turn OFF the power supply of the unit and turn ON again.
2. Press the RESET button on the remote controller.
Connect CN661 and
CN662.
Turn ON the power
Yes
supply and press
the EMERGENCY
OPERATION
switch.
W1. It is thought defective contact of the connector.
40
remote controller.)
Resistance
30.3 " ~ 37.0 "
Replace the deicer P.C.
board.
No
Does the unit operate
10 minutes or more?
Yes
Ok W1.