Mitsubishi Electric City Multi CMB-WP108V-G, Service Manual

Page: 210 / 301

[
IX
Troubleshooting ]
- 201 - HWE1113B GB
2. Phenomena
Although heating operation starts with the normal remote controller display, the capacity is not enough.
(1) Cause, check method and remedy
Cause Check method and remedy
1. Compressor frequency does not rise sufficiently.
Œ
Faulty detection of pressure sensor.
Œ
Protection works and compressor frequency does
not rise due to high discharge temperature
Œ
Protection works and compressor frequency does
not rise due to high pressure.
(1) Check pressure difference between the detected
pressure by the pressure sensor and the actual
pressure with self-diagnosis LED.
-> If the accurate pressure is not detected, check
the pressure sensor.(Refer to the page on Trouble-
shooting of Pressure Sensor)(page 207)
Note: Higher inlet pressure by the high pressure sensor
than the actual pressure causes insufficient capac-
ity.
SW1 setting
(2) Check the difference between the condensing tem-
perature (Tc) and the target condensing tempera-
ture (Tcm) with self-diagnosis LED.
Note: Higher Tc than Tcm causes insufficient capacity.
SW1 setting
Note: Protection works and compressor frequency does
not rise even at lower Tc than Tcm due to high dis-
charge temperature and high pressure.
At high discharge temperature:
Refer to 1102.(page 134)
At high pressure:
Refer to 1302.(page 136)
Hig h pressure sensor
Low pressure sensor
O
N
S W1
1 2 3 4 5 6 7 8 9
1
0
O
FF
O
N
S W1
1 2 3 4 5 6 7 8 9
1
0
O
FF
Condensing temperature T c
Target c ondensing temperature T c m
O
N
S W1
1 2 3 4 5 6 7 8 9
1
0
O
FF
O
N
S W1
1 2 3 4 5 6 7 8 9
1
0
O
FF