Trane PRGD series Installation, Operation And Maintenance Manual page 12

P P u u r r g g e e S S y y s s t t e e m m O O v v e e r r v v i i e e w w
the controller activates the pump-out cycle to
remove the accumulated non-condensables from
the purge tank. When enough non-condensables
have been removed and the purge compressor
suction temperature increases in response, the
controller terminates the pump-out cycle.
• S S a a t t u u r r a a t t e e d d c c o o n n d d e e n n s s e e r r t t e e m m p p e e r r a a t t u u r r e e s s e e n n s s o o r r . . This
sensor is mounted on the chiller. If the chiller is
running, the controller uses the value of this
temperature sensor to adjust the purge pump-out
initiate/terminate setpoints. It may be used to
prohibit pump-out if system conditions are too cool.
• S S a a t t u u r r a a t t e e d d e e v v a a p p o o r r a a t t o o r r t t e e m m p p e e r r a a t t u u r r e e s s e e n n s s o o r r . . This
sensor is mounted on the chiller. If the chiller is off,
the controller uses the value of this temperature
sensor to adjust the purge pump-out initiate/
terminate setpoints. It may be used to prohibit
pump-out if system conditions are too cool.
• C C a a r r b b o o n n t t a a n n k k t t e e m m p p e e r r a a t t u u r r e e s s e e n n s s o o r r . . This sensor is
mounted in the carbon tank of the purge system. It
provides feedback to the carbon regeneration
algorithm. The sensor and the controller function
much the same as a thermostat to control the
carbon tank heater.
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• L L i i q q u u i i d d l l e e v v e e l l s s e e n n s s o o r r . . This sensor resides in the
purge control panel. It monitors the status of the
normally closed float switch, which is mounted in
the bottom of the purge tank. If an adequate
amount of liquid fails to drain from the purge tank,
the float switch and sensor detect the condition and
prevent further purge operation.
• C C o o n n d d e e n n s s i i n n g g u u n n i i t t L L L L I I D D . . This LLID resides in the
purge control panel. It uses a high-capacity relay to
control the operation of the purge condensing unit.
• Q Q u u a a d d r r e e l l a a y y L L L L I I D D . . This LLID resides in the purge
control panel. It has four relay outputs that are used
to control the pump-out compressor, the carbon
tank heater, the regeneration solenoid valve, and an
alarm output.
• D D u u a a l l t t r r i i a a c c L L L L I I D D . . This LLID resides in the purge
control panel. It has two triac-type outputs that are
used to control the pump-out solenoid valve and
the exhaust solenoid valve. The purge system
draws its control power from the power supplies of
the chiller control panel.
PRGD-SVX01F-EN