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11. If low oil level problems persist, add another 1.89 L
(
1
/
2
gal.) of oil. Continue adding oil in 1.89 L (
1
/
2
gal.)
increments until the problem is resolved. If it is necessary
to add more than 5.75 L (1.5 gallons) of oil to the system,
contact your Carrier representative.
Oil Filter Maintenance —
Each compressor has its
own internal oil filter and each circuit also has an in-line exter-
nal filter. The internal oil filter pressure drop should be checked
and filter changed (if necessary) after the initial 200 to
300 hours of compressor operation. Oil line pressure loss is
monitored by the control and reported for each compressor as
the oil filter pressure drop. This information can be found in the
Pressures mode of the Navigator for each circuit. The ‘PRC.A’
sub-mode contains oil filter pressure differentials for each
Circuit A compressor (items ‘FD.A1’ ‘FD.A2’). Similarly, the
PRC.B sub-mode contains oil filter pressure differentials for
each circuit B compressor (items FD.B1, FD.B2). This pres-
sure differential (discharge pressure minus oil pressure, both
from pressure transducer inputs) is typically 15 to 20 psi
(103 to 138 kPa) for a system with clean internal and external
filters. To determine the oil pressure drop due to the oil lines
and external filter only, connect a gage to the oil pressure bleed
port. Compare this value to the discharge pressure read at the
Navigator. If this value exceeds 10 psi (69 kPa), replace the
external filter. The difference between the gauge pressure and
compressor oil pressure read at the Navigator is the pressure
drop through the internal oil filter. Replace the internal oil filter
if the pressure drop is greater than 25 psi (173 kPa) for 30HXC
and 30 psi (207 kPa) for 30GXN,R and 30HXA chillers.
REPLACING THE EXTERNAL OIL FILTER
Fully front seat (close) the angle valve on the filter and the
ball valve at the compressor. Connect a charging hose to the oil
pressure bleed port and drain the oil trapped between service
valves. A quart (liter) of oil is typically what is removed during
this process. Remove the charging hose.
Unscrew the nut from the other side of the filter and remove
the old filter. Remove protective plastic caps from new filter
and install. Draw a vacuum at the bleed port. Remove charging
hose. Open angle valve enough to let oil flow. Check both
fittings for leaks and repair if necessary. Backseat angle valve
and open ball valve.
REPLACING THE INTERNAL OIL FILTER — Close the
service valves at the compressor and drain the oil using the
bleed port. If the oil pressure does not bleed off using this
method it will be necessary to remove the entire circuit charge.
Using a
3
/
4
-in. Allen wrench, remove the internal filter access
cover (see Fig. 30). Remove the old filter. Replacement filters
(one for each compressor) are factory supplied to cover the
first changeout. After that, filters are field supplied. Lightly oil
O-ring in the filter and install with filter open end first into the
housing. Replace access cover and retorque to 75 ft-lb
(101 N-m). Follow procedure in previous section for opening
angle valve and purging lines. Check for leaks and repair if
necessary.
Compressor Changeout Sequence —
Compres-
sor service requires metric tools and hardware. Change
compressors according to the following procedure:
1. Turn off all main and control circuit power supplying the
machine.
2. Close the discharge and liquid valve(s), suction valve
(if equipped), and cooler inlet line service valve (if
equipped), oil line shutoff valve, and minimum load
shutoff valve (if equipped) for circuit to be changed.
Disconnect the oil inlet line from the compressor. Discon-
nect oil filter with fitting at shutoff valve side and set
filter and compressor inlet line assembly aside.
3. Remove any remaining refrigerant in the compressor and
refrigerant lines using proper reclaiming techniques. All
of the refrigerant that is in the cooler must be removed if
there is no suction service valve installed on the cooler.
4. Remove junction box cover of compressor to be changed.
Check main power leads for marked numbers. If no
numbers are visible on leads, mark leads with appropriate
numbers to match those printed on the ends of the
terminal lugs.
This is extremely important as power
leads MUST be installed on the exact terminals from
which they were removed.
5. Disconnect main power leads from compressor terminal
lugs. Mark remaining control circuit wires (connected
together with wire nuts) for ease of reconnecting later.
The following color scheme applies (verify with label
diagram on panel):
Loader 1
2 Violet wires
Loader 2
2 Pink wires
Motor Cooling Solenoid 1 Blue wire, 1 Brown wire *
Oil Solenoid
1 Orange wire, 1 Brown wire*
High-Pressure Switch
2 Red wires
*One lead from the motor cooling and oil solenoids are con-
nected together with a single brown wire.
Compressor oil is pressurized. Use proper safety precau-
tions when relieving pressure.
IMPORTANT: Cooler and condenser pumps must be
energized. Fluid must be flowing through heat exchang-
ers whenever adding or removing charge.
Fig. 30 — Compressor Component Diagram