McQuay seasoncon ALP-067A, Установка и техническое обслуживание

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Liquid Line Solenoid Valve
The liquid line solenoid valves,
which are responsible for automatic
pumpdown during normal unit operation,
maintenance.
do not normally require any
They may, however, require replacement of the solenoid
coil or of the entire valve assembly.
The solenoid coil may be removed from the valve body without opening
the refrigerant piping by moving pumpdown switches (PSl & PS2) to
the
pumpdown" position. The coil can then be removed from the
valve body by simply removing a nut or snap ring located at the top
of the coil. The coil can then be slipped off its mounting stud for
replacement. Be sure to replace the coil on its mounting stud before
returning pumpdown switches (PSl & PS2) to the "auto. pumpdown" po-
sition.
To replace the entire solenoid valve,
the unit must be pumped down
by use of the manual liquid line shutoff valve.
Thermostatic Expansion Valve
The expansion valve is responsible for allowing the proper amount of
refrigerant to enter the evaporator regardless of cooling load. It
does this by maintaining a constant superheat.
(Superheat is the
difference between refrigerant temperature as it leaves the evapor-
ator and the saturation temperature corresponding to the evaporator
pressure.) Typically,
15F.
superheat should run in the range of 10F to
On valves purchased through McQuay
the superheat setting can
be adjusted by removing a cap at the bottom of the valve to expose
the adjustment screw. Turn the screw clockwise (when viewed from the
adjustment screw end) to increase the superheat setting and counter-
clockwise to reduce superheat. Allow time for system rebalance af-
ter each superheat adjustment.
I N L E T
POWER ELEMENT
(CONTAINS DIAPHRAGM)
O U T L E T
SPRING
ADJUSTMENT SCREW
CAP
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