Hitachi RAC-25YH4, Service Manual, Page: 49 / 121

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Reversing valve (cooling “on” mode)
NOTE (9)
Notes:
(1) Condition for entering into Cool Dashed mode. When fan set to “Hi” or “Auto mode” and temperature difference between indoor temperature and set temperature has a
corresponding compressor rpm (calculated value in Table 2) larger than CMAX.
(2) Cool Dashed will release when i) a maximum 25 minutes is lapsed and ii) room temperature is lower than set temperature –3
°
C (thermo off) and iii) when room temperature
has achieved setting temperature –1
°
C then maximum Cool Dashed time will be revised to 20 minutes. And iv) indoor fan is set to Lo and Med fan mode and v) change operation
mode.
(3) During Cool Dashed operation, thermo off temperature is set temperature (with shift value) –3
°
C. After thermo off, operation continue in Fuzzy control mode.
(4) Compressor minimum “ON” time and “OFF” time is 3 minutes.
(5) During normal cooling mode, compressor maximum rpm CMAX will maintain for 60 minutes if indoor temperature is lower than CLMXTP. No time constrain if indoor temperature
is higher than CLMXTP.
(6)
(7) When fan is set to “Med”, compressor rpm will be limited to CJKMAX.
(8) When fan is set to “Lo”, compressor rpm will be limited to CBEMAX.
(9) During Cool Dashed, when room temperature reaches set temperature –1
°
C compressor rpm is actual rpm x DWNRATEC.
Temperature
Calculated
difference
compressor rpm
1.66°C
2500 min
–1
2.00°C
3000 min
–1
2.33°C
3500 min –1
2.66°C
4000 min
–1
CLMXTP
2min. 30sec. 2min. 30sec.
(with shift value)
Table 2 Compressor rpm
Item Temperature
Room
temperature
Outdoor
temperature
30°C
32°C
32°C
33°C
Thermo judgment (ON)
Thermo judgment (OFF)
Thermo judgment (ON)
Thermo judgment (OFF)
Table 1 Thermo judgment
button
When fan speed setting on remote control is “Hi” or “Auto” mode, and both room and outdoor temperatures (data based on out door unit) meet temperature judgment
(Off) shown in the table 1, the compressor rpm will be limited to CKYMAX.
RAS_25_35_AW_047-054_A3 2003.12.31, 10:57 AM 47