Operates But Does Not Heat - Mitsubishi Heavy Industries FDT200VSAWPVH Service Manual

Error code
None
Remote control:
1. Applicable model
All models
2. Error detection method
3. Condition of error displayed
4. Presumable cause
• Faulty 4-way valve operation
• Poor compression of
compressor
• Faulty body of EEVH, EEVC
• Faulty coil of EEVH, EEVC
• Faulty body of SV1
• Faulty coil of SV1
• Faulty temperature sensor
(Tho-D, Tho-H, Thi-R1, Thi-R2)
• Faulty pressure sensor PSL
• Insufficient amount of
refrigerant
Note:
LED Green Red
Keeps flashing Stays OFF
Indoor
Keeps flashing Stays OFF
Outdoor
5. Troubleshooting
Diagnosis
・ Is there any fouling,
clogging on indoor and outdoor heat exchanger?
・ Is there any short-circuit of outdoor and indoor unit air?
・ Is the filter in indoor unit
clogged?
NO
Is the difference
between the indoor return air temperature and
the remote control set temperature
small?
NO
Is the compressor
operating?
YES
Is the
compressor rotation
speed low?
YES
Is silent mode activated?
NO
Is there
any problem with
the sensor installation
(Tho-D, Tho-H, Thi-R1, Thi-R2, PSL)?
Is the connector (Tho-D, Tho-H, Thi-R1, Thi-R2, PSL)
disconnected or half-inserted?
Is the sensor insulation (for Tho-D,
Tho-H) insufficient?
NO
Is the detection
temperature and pressure of the sensors
(Tho-D, Tho-H, Thi-R1, Thi-R2, PSL) normal?
(By comparison between actual measured
value and Mente PC or
7-segment data)
YES
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Content

Operates but does not heat (1/2)

NO
" "
WAIT
message is displayed (for 3 seconds) when
performing cooling, dehumidifying and heating
operations from the remote
control.
-
'21 • PAC-SM-383
Countermeasure
Correct abnormal condition.
YES
Change the remote control set
YES
temperature.
Compressor refrigerant oil
protection control at starting
is activated. For the contents
of control, refer to the
compressor start control of
the microcomputer control
functions.
YES
Compressor may be stopped
by the error detection control.
For the contents of control, refer
to anomalous stop control by
controlling compressor rotation
speed of microcomputor control
NO
functions.
Inspect the followings.
NO
• Minor clogging of filter
• Minor clogging of heat
exchanger
• Minor short-circuit
• Minor shortage of
refrigerant amount
• Poor compression of
compressor
Cancel silent mode.
YES
Correct to the proper
YES
condition.
Chenge the sensor
NO