CG-SVX038A-EN
37
Maintenance
Because scroll compressors are a uniquely different
design from traditional reciprocating compressors, their
operating characteristics and requirements are a
departure from the reciprocating compressor technology.
Compressor Oil
The R-410A scroll compressor uses POE oil as required by
the manufacturer of the compressor. Refer to compressor
manufacturer for exact type and amount of oil in the
specific model in question.
Oil Level.
While the compressor is running, the oil level
may be below the sight glass
but still visible through the
sight glass
. The oil level should NEVER be above the sight
glass!
Oil Appearance.
If the oil is dark and smells burnt
, it was
overheated because of compressor operation at extremely
high condensing temperatures, a compressor mechanical
failure, or occurrence of a motor burnout.
If the oil is black
and contains metal flakes
, a mechanical failure has
occurred. This symptom is often accompanied by a high
amperage draw at the compressor motor.
Notes:
•
If a motor burnout is suspected, use an acid test kit to
check the condition of the oil. If a burnout has occurred,
test results will indicate an acid level exceeding
0.05 mg KOH/g.
•
The use of commercially available oil additives is not
recommended. Liability for any detrimental effects
that the use of non-approved products may have on
equipment performance or longevity must be
assumed by the equipment owner, equipment
servicer, or the oil additive manufacturer.
Scroll Compressor Functional Test
Since the scroll compressor does not use discharge or
suction valves, it is not necessary to perform a pump-
down capability test, i.e. a test where the liquid line valve
is closed and the compressor is pumped in a vacuum to
see if it will pump-down and hold. If fact, this kind of test
may actually damage the scroll compressor!
The proper procedure for checking scroll compressor
operation is outlined below:
1.
Verify that the compressor is receiving supply power of
the proper voltage.
2. With the compressor running, measure the suction
and discharge pressures/temperatures to determine
whether or not they fall within the compressor
operating map shown in figure below.
See
“Checking Operating Conditions,” p. 34
for normal
operating pressure ranges for the unit.
WARNING
Hazardous Service Procedures!
Failure to follow all precautions in this manual and on
the tags, stickers, and labels could result in death or
serious injury.
Technicians, in order to protect themselves from
potential electrical, mechanical, and chemical hazards,
MUST follow precautions in this manual and on the
tags, stickers, and labels, as well as the following
instructions: Unless specified otherwise, disconnect all
electrical power including remote disconnect and
discharge all energy storing devices such as capacitors
before servicing. Follow proper lockout/tagout
procedures to ensure the power can not be
inadvertently energized. When necessary to work with
live electrical components, have a qualified licensed
electrician or other individual who has been trained in
handling live electrical components perform these
tasks.
NOTICE:
Compressor Damage!
Do not pump the scroll compressor into a vacuum.
Scroll compressors can pull internal low vacuums when
the suction side is closed or restricted. This, in turn,
may cause the internal Fusite
®
terminal to arc, resulting
in compressor damage or failure. It may also trip the
circuit breakers, blow fuses, or trip the discharge
thermostat.
Summary of Contents for Cold Generator
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