Mitsubishi KXZ Series - Page 185

(1) Operation of major functional components under each operation mode
Operation mode
Functional components
Cooling/Dehumidifying Heating
Compressor
ON
Compressor
OFF
All stop by
remote control
Compressor
ON
Compressor
OFF
All stop by
remote control
Magnetic contactor for
compressor (52C1)
ON OFF ON OFF
Crankcase heater (CH1) ON/OFF*1 ON/OFF*1 ON ON/OFF*1 ON/OFF*1 ON
Compressor (CM1)
Cooling low
pressure control
Stop Stop
Heating high
pressure control
Stop Stop
Fan motor (FMo1)
Normal control Stop Stop Normal control Stop Stop
4-way valve (20S) OFF OFF OFF ON ON ONOFF*2
Electronic expansion
valve for sub-cooling coil
(EEVSC)
Normal control Fully closed Fully closed Fully closed Fully closed Fully closed
Electronic expansion
valve for heating (EEVH)
Fully open Fully open Fully open
Normal
control
Fully closed Fully closed
Notes (1) Above list shows the conditions at steady state under each operation mode.
(2) *1 According to discharge superheat
(3) *2 It turns OFF after retaining ON condition for a certain minutes
(2) Compressor control
Compressor rotation speed at cooling (dehumidifying) and heating operations are as follows.
Unit: rps
Item
Model
Cooling (Dehumidifying) operation Heating operation
FDC121KXZE1-W 40 - 77 20 - 110
FDC140KXZE1-W 40 - 100 20 - 110
FDC155KXZE1-W 40 - 106 20 - 110
(3) Outdoor fan control
(a) Control contents of fan tap and fan speed
Outdoor fan tap
Fan speed
Cooling Heating
FMo1 [min
-1
] FMo1 [min
-1
]
0th speed 0 0
1st speed 200 130
2nd speed 300 300
3rd speed 350 350
4th speed 500 500
5th speed 600 600
6th speed 740 740
7th speed 820 820
8th speed 870 870
9th speed – 950
(b) Fan control during cooling
During cooling and dehumidifying, fan speed is controlled in accordance with the high pressure (sensed by
PSH) and the outdoor air temperature (sensed by Tho-A).
(i) Initial fan speeds are as follows.
Initial outdoor fan speed at cooling
Model 15°C < Outdoor air temperature < 20°C 20°C ≦ Outdoor air temperature
All models 3rd speed 5th speed
Outdoor air temperature ≤ 15°C
1st speed
(ii) During normal operation, the speed is changed in accordance with the high pressure value.
(A) Normal control
ON/OFF ON/OFF
(c) Fan control during heating
During heating, fan speed is controlled in accordance with the low pressure (sensed by PSL).
(i) Initial fan speeds are as follows.
• Outdoor fan initial speed during heating
Model Speed
All models 6th speed
(ii) During normal operation, the speed is changed in accordance with the low pressure value.
(4)Defrost operation
• Temperature condition of defrost operation
(a) Starting conditions
Defrost
the following conditions.
(i) When 33 minutes of cumulative compressor operation time has passed since heating operation started.
(ii) When 33 minutes of cumulative compressor operation time has passed since defrost operation ended.
(iii) When 8 minutes has passed since the compressor turned ON from OFF status.
(iv) When 8minutes has passed since one outdoor fan turned ON from OFF status.
(v) After all abo
①
When the outdoor heat exchanger temperature (sensed by Tho-R) and the ambient air temperature (sensed by
Tho-A) dropped below the defrost operation start temperature in Fig. 1 for 30 seconds continuously
②
When the suction pressure saturated temperature calculated by the low pressure (sensed by PSL) and the ambient
air temperature (sensed by Tho-A) dropped below the
defrost operation start temperature in Fig. 2 for 30 seconds
continuously
TR: Heat exchanger temperature (°C)
TA: Ambient air temperature (°C)
TA: Ambient air temperature (°C)
Fig. 1
Cold region
Standard
(Factory setting)
Defrost operation start zone
-2
-6
-15
-19
-21
-25
-20 -15 6
Without J15
Cold region specification
With J15
SST: Suction pressure saturated temperature (°C)
Fig. 2
Cold region
Standard
(Factory setting)
Defrost operation start zone
-6
-10
-19
-23
-25
-29
-20 -15 6
Without J15
Cold region specification
With J15
(b) Ending conditions
Defrost operation stops when a
(i) When 12 minutes has passed since defrost operation started
(ii) When the outdoor heat exchanger temperature (sensed by Tho-R) is detected 12°C or higher continuously for 10
seconds
(iii) When it has detected the high pressure (HP) ≥ 3.0MPa
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'20 • KX-T-373