GE AB09SC2VHA, Руководство по обслуживанию

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OUTDOOR TECHNICAL OVERVIEW
ENGLISH
B-12
Operations
Base Pan Heater Control Logic
When the compressor starts in the heating mode, the
following conditions will apply:
Troubleshooting the Base Pan Heater Error:
Step 1:
Check the pan heater for an open circuit or shirt circuit.
Unplug the connector from main control PCB. Test the
resistance between the two pins of the pan heater connector.
It should be 0.28-0.379KΩ. If out of range, change the pan
heater. If normal go step 2.
Step 2:
Check the main control board pan heater output port . Unplug
the connector from main control PCB. Run the ODU with
manually forced heating (Set the display board SW 1-1 as
ON). Test the voltage between the two heater output pins, it
should be 208-230Vac.
Defrost Control
In the heating mode and along with the ambient sensor, the
defrost sensor monitors the temperature of the outdoor
coil to determine if defrost is needed. If the compressor has
been running for 10 minutes continuously and for 45 minutes
overall, the difference between the ambient sensor (Ta) and
the defrost sensor (Te) will be checked. The system will
initiate the defrost cycle if the following conditions can be met
for 5 continuous minutes:
Te ≤ C x Ta-A
Te: Defrost temperature sensor
Ta: Ambient temperature
C: 0.80 if Ta < 32°F/0°C, 0.60 if Ta ≥ 32°F/0°C
A: 8, moderate climate (factory setting). 6, severe climate
(alternate setting)
End Defrosting:
If the defrost sensor (Te) detects the temperature of the
outdoor coil is above 44°F(7°C) for 60 seconds or is above
54°F(12°C) for 30 seconds, the defrost cycle will terminate. If
these temperatures cannot be reached, the defrost cycle will
automatically terminate in 10 minutes.
Timed Defrost Option:
• When the outdoor ambient temperature sensor detects Ta
is less than 32°F(0°C)
• In heating mode, compressor runs continuously for 60
minutes or for 240 minutes in all
• When the above conditions are met, the system will defrost.
Defrosting frequency is 68 HZ, with a defrosting time of 8
minutes.
Outdoor Temperature Pan Heater
>37
o
F(3
o
C) OFF
28
o
F(-2
o
C) to 34
o
F(1
o
C) OFF 20min. ON 10min.
10
o
F(-12
o
C) to 25
o
F(-4
o
C) OFF 15min. ON 15min.
<10
o
F(-12
o
C) ON
Discharge Sensor Protection
If the discharge temperature is higher than normal, the compressor will slow down to lower the temperature.
Discharging
t
emp.
Td
Reduce FQY rapidly 2HZ/S
Reduce FQY rapidly 1HZ/S
Reduce FQY slowly 1HZ/10S
Remain FQY
Increase FQY slowly 1HZ/10S
118
℃
115
℃
112
℃
109
℃
105
℃
95
℃
Unitary:
Multi:
Dischar
gin
g
tem
p.
Td
Reduce FQY rapidly 1HZ/S
Reduce FQY slowly 1HZ/10S
Remain FQY
Increase FQY slowly 1HZ/10S
If keeping for 10s, the unit stops, 3 minutes later, the unit can
re-startup. If in 60 minutesthe unit occurs alarm for 3 times, the
failure can be eliminated.
Remain FQY
If the discharge temperature sensor reaches 243F for 10
seconds, the compressor will shut off. After the 3-minute
time delay, the compressor will restart. If this occurs
three times in a 60-minute period, the compressor will
lock out. Until the cause of the high temperature is
discovered, the compressor will not restart until the
power is interrupted then restored.
203
℉
( 95
℃
)
207
℉
( 97
℃
)
225
℉
( 107
℃
)
234
℉
( 112
℃
)
243
℉
( 117
℃
)