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Service
After all checks are made and it has been determined
that compressor servicing is necessary then proceed per
the following instructions to remove and replace the
necessary parts. Checks should be made during this pro-
cedure such as observing wear patterns, all clearances,
evidence of unusual material foreign to the compres-
sor, etc.
PREPARATION FOR SERVICE
Read the general introductory information and specific
service instructions for intended task. Be sure you un-
derstand all the above items thoroughly, if you need
assistance, call the local YORK office. As mentioned
before, have an as-built print, proper tools, and parts
on hand.
Always follow tag out/lockout procedures to prevent
unexpected operation.
Be sure you know the exact type of
refrigerant and oil in the system you
are working on. Be sure proper re-
placement stocks are available.
To ensure compliance with the Clean Air Act and still
provide efficient refrigerants, manufacturers are fre-
quently bringing out new products. These rather ex-
otic compounds and blends are similar in performance
to the older series of refrigerants, but they are not con-
sidered to be "drop in" replacements.
Newly developed HFC and HCFC refrigerant com-
pounds and blends, together with some synthetic oils,
are not compatible with most of the older types. In addi-
tion, elastomers and gasket materials used prior to 1992
that were recommended for specific refrigerants and ap-
plications may not be suited to the new products.
Be sure you know the exact type of refrigerant and oil
that is in the system on which you are working, storage
containers are available and suitable, and proper re-
placement stocks are available if required.
As of November 1994, the EPA requires certification
of all personnel engaged in service of air conditioning
and refrigeration systems. A set of specific guidelines
has been issued by the EPA and failure to comply with
these standards may result in penalties in the form of
fines per day to the service technician or service com-
pany. The EPA standards are revised frequently and it
is the responsibility of the service technician and his/
34
her organization to be aware of current regulations and
to comply with them.
Be careful that the system is not sub-
jected to a freeze condition during the
transferring of refrigerant.
Be sure that rigging provided is rated for the Series M
compressor components. For example; a 55" two-stage
top half weighs more than three tons. Consult Table 2
and Table 3 for approximate component weights.
Use gantries with chain falls or overhead cranes if pos-
sible. Mobile cranes and fork trucks are subject to abrupt
movements. If cranes or fork trucks must be used, uti-
lize them with chain falls for delicate positioning.
Use extreme caution when rigging the total compres-
sor weight off the top half casing lugs. Attachment rig-
ging may be steel cable, chain, or approved straps. Be
sure of the rigging working strength and pay attention
to lifting angles which may derate this devices.
When lifting the casing top half, it is recommended to
rig from a center point to the four casing lugs. Secure
the four lines from the casing hooks at the center point
with a large shackle to prevent the lines from running
through the hook and allowing the casing to abruptly
shift. Use one or more come-a-longs rigged off of the
lifting hook to level the top half if needed.
Depending upon the compressor location, local
weather or job hazards, the compressor may be relo-
cated into a maintenance shop. Compressor realign-
ment is not difficult nor time consuming. You may
actually save time as well as having better conditions
for a successful overhaul.
Have sufficient guide pins on hand. You need four bul-
let-nose pins for the top half and at least three pins for
the PRV housing and sump. The suction and bearing
support and shaft seal cover are heavy and requires at
least two guide pins. The oil pump housing requires at
least two pins. An alternate source is all-thread studs
used to bolt up high pressure flanges. Be aware of the
thread pitch so the housings are not damaged by cross
threading. The overall length and positioning will vary
with the oil piping and control locations. When remov-
ing or installing the sump, it may be necessary to screw
a short stud into one of the bottom bolt holes at the rear
of the sump and slip a piece of pipe over it to get lever-
FORM 220.11-NM2 (602)
4
YORK INTERNATIONAL
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