Mitsubishi Heavy Industries FDTCVA SERIES Technical Manual page 274

± Models FDCVA302~1002
Are the
characteristics of
YES
the outdoor heat exchanger
thermistor
normal?
NO
Replace the outdoor heat
exchanger thermistor.
Is the unit normal?
YES
Set temperature for protective control
Protective stop
Operable
51 65
Outdoor heat exchanger temp. (˚C)
± Display Conditions
The error occurs when the outdoor heat
exchanger temperature exceeds 65˚C 5
times within 60 minutes, or is kept 65˚C
or higher.
Is there cooling overload
operation?
Is high pressure control
normal?
Is there any gap between
actual temperature and
sensed temperature by
the microcomputer?
YES
The outdoor control PCB
is faulty. Replace it.
273
-
Check the unit side.
• Is there a short circuit in the outdoor unit?
• Is the installation space proper?
• Is it overcharged?
• Is the heat exchanger dirty or clogged?
When the following conditions are established, compressor speed is
reduced every minute down to the minimum speed at lowest.
Ambient temperature is 40˚C or higher
The outdoor heat exchanger temperature exceeds the set value
mentioned below.
Item
Minimum compressor speed (rps)
Outdoor heat exchanger temperature (˚C)
Outdoor unit heat exchanger
thermistor(Tho-R)
Resistance-temperature characteristics
15
10
5
0 20 40
Temperature (ºC)
-
Model
302 402~602 802, 1002
20 40
52~58 52~58
60 80 100
30
54~60