Trane CVGF1000, Инструкция по установке, эксплуатации и обслуживанию

Страница: 123 / 128

Pump. Place oil pump in manual mode. Check the oil pressure gauge readings and
calculate the differential oil pressure by subtracting the oil sump pressure reading
from the discharge oil pressure reading.
I f t h e d i f f e r e n t i a l
pressure is between 18 to 22 psid (124¬151 kPa), the oil pressure regulating valve
should not be adjusted. If the oil pressure switch is not closed at pressures above
12 psid (82kPa), the switch is defective and should be replaced. If the switch is
closed the unit will not start due to a low oil pressure diagnostic. If the differential
oil pressure cannot be achieved, the oil pump may be running backwards.
3. To reverse the oil pump motor rotation, two leads must be swapped on the oil
pump motor contactor. Be sure to remove all power from the unit before doing
any
electrical wiring changes.
Note: Be sure to perform the Bump Start test to determine proper compressor ro-
tation before operating the chiller.
If the differential oil pressure measured is below 12 psid (82 kPa), the oil filter may
be plugging or the regulator may need adjustment.
4. Then check the pressure drop across the oil filter, connect a gauge to the service
valve before the oil filter and another gauge to the service valve after the oil filter.
Subtract the pressure reading taken from after the oil filter from the gauge before
the oil filter to obtain the pressure drop. If the pressure drop is excessive (more
than 8 psid (54 kPa)), shut the oil pump off and replace the oil filter per the proce-
dure outlined previously.
5. When the oil filter change is completed, check the differential oil pressure and if it
is below 18 psid (124 kPa), adjust the oil pressure regulator to obtain a reading of
between 18 to 22 psid (124¬151 kPa). If the pressure drop across the filter is not
excessive, but the oil differential pressure is below 18 psid, adjust the oil pressure
regulating valve to obtain 18 to 22 psid (124-151 kPa) oil pressure. To increase
pressure, remove the oil pressure regulator cap and screw the regulator stem in
a clockwise direction. Be sure to replace the cap and tighten when adjustment is
complete.
6. Remove the pressure gauges when all diagnostic work is complete. Be sure and
replace and secure any valve caps which were removed.
CVGF Oil Pump
The oil pump for the CVGF is a positive displacement, direct drive pump, three phase
motor. The motor must be phased correctly to provide positive differential oil pressure.
This pump and motor is located within the oil sump and can not be serviced without
recovering the refrigerant and removing the oil from the machine.
Refrigerant Charge
If a low refrigerant charge is suspected, first determine the cause of lost refriger-
ant. Once the problem is repaired follow the procedures below for evacuating and
charging the unit.
WARNING
CVGF-SVX03B-EN
123
Periodic Maintenance