Outline Of Heating Operation - Mitsubishi Heavy Industries SRK20ZSX-W Service Manual

1.3 Outdoor units

1.3.1 Outline of heating operation

(1) Summary
(a) Capacity control
(i) Indoor unit SRK ** ZSX models only
Model
Capacity
(ii) Indoor unit except SRK ** ZSX models
Model
Capacity
Capacity control is within the range shown above. If demand capacity of the indoor units exceeds the maximum capac-
ity of the outdoor unit, the demand capacity will be proportionally distributed.
(b) Outdoor compressor speed control
Indoor compressor command total speed value
0 rps
A rps or less
More than A rps, but B rps or less
More than B rps
Values of A, B
Item
A
B
(2) Operation of major functional components in heating mode
Operation
Functional
components
Command speed
Fixed
Indoor
unit fan
Automatic
Outdoor unit fan
Electronic
expansion valve
Compressor
SCM71ZS-W SCM80ZS-W
1.1 9.4 kW 1.1 9.8 kW
SCM71ZS-W SCM80ZS-W
1.1 9.1 kW 1.1 9.6 kW
Decision speed
0 rps
A rps
A rps to B rps
B rps
Model
SCM71ZS-W SCM80ZS-W
20 rps
120 rps
Thermostat OFF
Heating
(All indoor units)
Multi-operation rpm calculated based
on the rpm required for each indoor unit (All indoor units)
According to mode switching
According to command speed
According to outdoor unit speed
According to decision
According to stop mode
speed
ON
Thermostat OFF
(Some of indoor units)
0
0
(Thermostat off units)
According to mode switching
Hot keep
According to command speed
Hot keep
OFF According to outdoor unit speed
According to heating stop unit control
(Thermostat off units)
OFF ON
67
- -
'19 • SCM-SM-276
Fan, stop, abnormal stop Failure
(Some of indoor units) (Outdoor unit)
0
(Fan, stop, abnormal stop units) (All units)
Hot keep
Hot keep
According to heating stop unit control
According to stop mode
(Fan, stop, abnormal stop units)
ON
0
OFF
OFF