This section contains Direct Support Maintenance
instructions authorized by the Maintenance Allocation Chart (MAC),
Appendix B, and by the Source, Maintenance, and Recoverability (SMR)
coded items to support the water chiller.
When the refrigeration system must be opened for
any reason, carefully discharge the refrigerant
Avoid contact with liquid refrigerant.
Severe freezing of body tissues can take place
with extreme rapidity.
inhalation of refrigerant gas, and ventilate the
area in which it is released.
Refrigerant gas in
contact with flame or hot surfaces is converted
Phosgene is a highly toxic gas with
an odor similar to newly mown grass or hay.
The refrigerant system is illustrated by the refrigerant flow
It is a mechanical, vapor-cycle circuit made up of
evaporator, thermal expansion valve, compressor, condenser,
and the necessary valves and cutout devices for automatic
control during operation.
The thermal expansion valve releases high-pressure liquid
refrigerant into the evaporator at reduced pressure.
The liquid refrigerant begins to vaporize by absorbing heat
from the water passing through the tubing of the evaporator.
The heated vapor is pulled from the evaporator section by the
compressor, and forced into the condenser section under high
There it is cooled and condensed back into a
The heat released during condensation
The liquid refrigerant flows from the
sight glass into the filter-drier and
expansion valve to repeat the cycle.
is carried off by the
condenser through a
then to the thermal
If the temperature control switch (low temperature thermal
switch) becomes satisfied, the switch will open, grounding
the ignition system, and stopping the gasoline engine.