SYSTEM MAINTENANCE
GENERAL
On initial startup and periodically during operation, it will be
supports on each side of the unit adjacent to the compressors.
necessary to perform certain routine service checks. Among
The gauges are factory installed with a manual shutoff valve
these are checking the compressor oil level and taking
con-
on each gauge line. The valves should be closed at all times
densing,
suction and oil pressure readings. During operation,
except when gauge readings are being taken. On units
the oil level should be visible in the oil sightglass with the
ordered without gauges, Shrader fittings should be installed
compressor running. On units ordered with gauges,
conden-
in the plugged ports provided on the suction and discharge
sing, suction and oil pressures can be read from the vertical
King valves on each compressor circuit.
FAN SHAFT BEARINGS
The fan shaft bearings are of the permanently lubricated type. No lubrication is required.
ELECTRICAL TERMINALS
CAUTION:
Electric
shock hazard. Turn off
all
power before continuing with the follow.
ing service.
All power electrical terminals should be retightened every six months, as they tend
to loosen in service due to normal heating and cooling of the wire.
COMPRESSOR OIL LEVEL
Because of the large refrigerant charge required in an air
cool-
ed condensing unit, it is usually necessary to put additional
oil into the system. The oil level should be watched carefully
upon initial startup and for sometime thereafter.
At the present time, Suniso No.
3GS,
Calumet R015, and
Texaco WF32 oils are approved by
Copeland
for use in these
compressors. The oil level should be maintained at about
one-
third of the sightglass on the compressor body.
Oil may be added to the
Copeland
compressor through the
oil fill hole in the crankcase. To add oil, isolate the crankcase
and pour or pump in the necessary oil. If the system contains
no refrigerant, no special precautions are necessary other
than keeping the oil clean and dry.
If the system contains a refrigerant charge, close the
suc-
tion valve and reduce crankcase pressure to 1 to 2 psig. Stop
the compressor and close the discharge valve.
Add the required amount of oil. During the period the
com-
pressor is exposed to the atmosphere, the refrigerant will
generate a vapor pressure, retarding the entrance of
con-
taminants. Before resealing the compressor, purge the
crankcase by opening the suction valve slightly for 1 or 2
seconds. Close the oil port, open the compressor valves and
restore the system to operation.
CONDENSERS
Condensers are air cooled and constructed with
s/8”
O.D.
in-
ternally
finned copper tubes bonded in a staggered pattern
into slit aluminum fins. No maintenance is ordinarily required
except the occasional removal of dirt and debris from the
out-
side surface of the fins. McQuay recommends the use of
foaming coil cleaners available at air conditioning supply
outlets. Use caution when applying such cleaners as they may
contain potentially harmful chemicals. Care should be taken
not to damage the fins during cleaning. Periodic use of the
purge valve on the condenser will prevent the buildup of
non-condensables.
REFRIGERANT SIGHTGLASS
The refrigerant sightglasses should be observed period-
ically. (A monthly observation should be adequate.) A clear
or a restriction elsewhere in the system. On sightglasses
glass of liquid indicats that there is adequate refrigerant
ordered from McQuay as part of the “Liquid Line Accessory
charge in the system to insure proper feed through the
ex-
Kits” listed on page 8, an element inside the sightglass
in-
pansion
valve. Bubbling refrigerant in the sightglass indicates
dicates what moisture condition corresponds to a given ele-
that the system is short of refrigerant charge. Refrigerant gas
ment color. If the sightglass does not indicate a dry
condi-
tion after about 12 hours of operation, the unit should be
flashing in the sightglass could also indicate an excessive
pressure drop in the line, possibly due to a clogged filter-drier
pumped down and the filter-driers changed.
IM 269
/
Page 49
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