Hitachi RAS-(4-12)HNP(1)(E) - Prevention Control for Excessively High Discharge Gas Temperature

5 Control System
157
SMGB0087 rev.0 - 12/2013
5
5.5.3 Prevention control for excessively high discharge gas temperature
Heating operation
IU
air outlet
temperature
≥ 65ºC
Yes
CMC: OFF
No
< 65ºC
Compressor:
OFF
3
min
progress
≥ 65ºC
IU
air outlet
temperature
< 65ºC
No
set
temp is
lower than air intake
temp
CMC: ON
Compressor:
ON
Yes
IU
air outlet
temperature
≥ 60ºC
Yes
Power ti YH2: OFF
No
< 60ºC
CMC:
ON
< 35ºC
IU
air outlet
temperature
≥ 35ºC
No
IU
demand
frequency > 90 Hz
Power to YH2: ON
Yes
Power to EHW:
OFF
(for unit with EHW)
Power to
EHW: ON
(for unit with EHW)
Heater control for indoor unitThermo-ON/OFF control for indoor unit
IU: Indoor unit