Schreiber Chillers 300AC-MRI - Manual (Page 25)

SERVICE BULLETIN
HERMETIC COMPRESSOR ELECTRICAL TERMINAL VENTING
CAN BE DANGEROUS
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When the insulating material, which supports a hermetic compressor electrical terminal,
suddenly disintegrates due to physical abuse or as a result of an electrical short
between the terminal and the compressor housing, the terminal may be expelled,
venting the vaporous and liquid contents of the compressor housing and system.
If the hermetic compressor terminal PROTECTIVE COVER is not properly in place with
its weatherproofing gasket (if required) and bale strap fastening device secured, there is
a remote possibility if a terminal vents, that the vaporous and liquid discharge can be
ignited, spouting flames several feet, causing potentially severe or fatal injury to anyone
in its path.
The discharge from a venting terminal can be ignited external to the compressor if the
terminal PROTECTIVE COVER is not properly in place and if the discharge impinges
on a sufficient heat source such as, but not limited to, an open flame, electric heater, or
an electrical spark.
Ignition of the discharge can also occur at the venting terminal or inside the motor-
compressor enclosure, if there is sufficient contaminant air present in the system and an
electrical arc occurs as the terminal vents.
Ignition cannot occur at the venting terminal without the presence of contaminant air,
and cannot occur externally from the venting terminal without the presence of an
external ignition source.
It is, therefore, essential that any air in a refrigeration, air conditioning, or heat pump
system be completely removed when the system is manufactured - when the system is
installed - and whenever the system is field processed as a result of field service. Field
service includes, but is not limited to, leak repairs or compressor replacement.
Eliminating air within the system prevents ignition at, or in, the hermetic compressor if a
terminal should vent, thereby reducing the hazard potential.
To reduce the possibility of external ignition, all open flame, electrical power, and other
heat sources should be extinguished or turned off prior to servicing a system.
Before using a soldering or welding torch to remove or repair tubing, make sure all the
system refrigerant charge has safely been released.
A venting terminal presents no danger to servicing personnel or anyone else in the
vicinity if the compressor terminal PROTECTIVE COVER is properly in place as shown
on Tecumseh Products Company drawings and diagrams using the parts as shown on
Tecumseh Products Company bills of material.
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