Heating Low Outdoor Temperature Protective Control - Mitsubishi Heavy Industries SRK20ZJX-S Service Manual

B or D.
3) Reset conditions:
Upper A
Lower B
OFF
11(8)
Outdoor air temperature(
Note(1) Value in ( ) are for the model SCM40, 45.

(7) Heating low outdoor temperature protective control

(a) Operating conditions:
(b) Detail of operation:
(c) Reset conditions:
(8) Freezing cycle system protective control
(a) Starting condition: This control starts when the following conditions are met.
1) When it has elapsed 30 minutes after the compressor was changed from OFF to ON in the cooling operation mode for
more than 5 minutes.
2) When the compressor command speed has met the following conditions.
3) When the indoor air temperature of running indoor unit (Th1) and the indoor heat exchanger temperature (Th2) have
met the following condition even on one unit.
Compressor
Unit
command speed
1 40 (60) rps
2
50 (70) rps
3
60 (80) rps
4 70 rps
Note (1) Value in ( ) are for the model 40 – 50.
(b) Contents of control
1) Stop the compressor and delay the start, and then restarts.
2) Compressor stops by the abnormal stop when the compressor stop has occurred 3 times in one hour.
(9) Crankcase heater
(a) Operating conditions (When all the conditions below are satisfied)
After the operation mode is changed to stop and the compressor command speed becomes 0 rps continuously for 30 minutes.
When the temperature detected by the outdoor air temperature (Th2) is 10°C or lower after the compressor stops.
Upper C
Lower D
13(10) 16 17
º )
-8 -6 4
Outdoor air temperature(°C)
Indoor air temperature
(Th1, ℃ )
10 < = Th1 < = 40
B or D
B or D
h 8
Item
Model
SCM40, 45
SCM50
SCM60, 71, 80
h
Lower limit 40 rps (model 50:45 rps)
Lower limit 35 rps
Normal operation
6
6
Indoor air temperature (Th1) and indoor
heat exchanger temperature (Th2)
Th1 - 4 < Th2
Th1 - 3 < Th2
Th1 - 2 < Th2
36
- -
when the thermo becomes OFF, the speed is
'10 • SCM-SM-094
(model 60 ~ 80:11 ).
A B C
90 35 75
90 35 75
90 30 75
4
Duration
5 minute
Unit: rps
D
40
40
40