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 TM 55-1905-219-14-9
4-35.4. WATER REGULATING VALVE - AIR CONDITIONING - MAINTENANCE INSTRUCTIONS.
LOCATION
ITEM
ACTION
REMARKS
a.
The water regulating valve automatically controls the sea water flow through the condenser to
maintain a relatively constant condensing pressure and temperature. The water regulating valve is actuated by
the refrigerant head pressure in the condenser and must be adjusted so as to maintain the required condensing
pressure and to shut off water flow when the compressor is stopped. The water regulating valve is located in
the condenser water outlet line.
b.
Adjust the condenser water regulating valve to maintain a discharge pressure of 90 to 125 psig
(620.6 to 861.9 kPa).
c.
With the system under normal operation, feel the liquid lines up to the expansion valves. If the
expansion valves are hissing loudly or the liquid lines is cold where it leaves the solenoid valve or strainer,
there is inadequate subcooling or restricted liquid refrigerant flow. Check head pressure and adjust the water
regulating valve as required. If the valve setting is correct, check for obstructions in the liquid line (such as a
clogged strainer). Clean or repair obstructed parts.
d.
Refrigerant head pressure from condenser is applied to bellows assembly. When refrigerant
head pressure increases, the bellows plate is compressed forcing the bellow push rod upward, moving the
valve seat in the opening direction and allowing increased water flow through condenser. As the valve unseats,
pressure is exerted upward through valve disc, valve disc holder, guide post and valve center assembly screw
to compress range spring.
e.
Increase water flow through condenser reduces head pressure. When head pressure
decreases, the range spring expands moving the valve seat in the closing direction and reducing water flow.
NOTE
If compressor operates in high ambient temperatures, gas
pressure may at times remain high enough to cause valve to
partly open when compressor is idle. In such a case, raise
opening of valve just enough to cause valve to close during
compressor stand-by periods.
f.
It is not necessary to disconnect the valve to perform service or repair.
4-964
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