Troubleshooting; Diagnostics; Carbon Regeneration Temperature - Trane PRGD series Installation, Operation And Maintenance Manual

Troubleshooting

Use this section to assist you in diagnosing operational
problems with the purge system.
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R R e e f f r r i i g g e e r r a a n n t t u u n n d d e e r r H H i i g g h h P P r r e e s s s s u u r r e e ! !
F F a a i i l l u u r r e e t t o o f f o o l l l l o o w w i i n n s s t t r r u u c c t t i i o o n n s s b b e e l l o o w w c c o o u u l l d d r r e e s s u u l l t t i i n n
a a n n e e x x p p l l o o s s i i o o n n w w h h i i c c h h c c o o u u l l d d r r e e s s u u l l t t i i n n d d e e a a t t h h o o r r
s s e e r r i i o o u u s s i i n n j j u u r r y y o o r r e e q q u u i i p p m m e e n n t t d d a a m m a a g g e e . .
S S y y s s t t e e m m c c o o n n t t a a i i n n s s o o i i l l a a n n d d r r e e f f r r i i g g e e r r a a n n t t u u n n d d e e r r h h i i g g h h
p p r r e e s s s s u u r r e e . . R R e e c c o o v v e e r r r r e e f f r r i i g g e e r r a a n n t t t t o o r r e e l l i i e e v v e e p p r r e e s s s s u u r r e e
b b e e f f o o r r e e o o p p e e n n i i n n g g t t h h e e s s y y s s t t e e m m . . S S e e e e u u n n i i t t n n a a m m e e p p l l a a t t e e f f o o r r
r r e e f f r r i i g g e e r r a a n n t t t t y y p p e e . . D D o o n n o o t t u u s s e e n n o o n n - - a a p p p p r r o o v v e e d d
r r e e f f r r i i g g e e r r a a n n t t s s , , r r e e f f r r i i g g e e r r a a n n t t s s u u b b s s t t i i t t u u t t e e s s , , o o r r r r e e f f r r i i g g e e r r a a n n t t
a a d d d d i i t t i i v v e e s s . .
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H H a a z z a a r r d d o o u u s s V V o o l l t t a a g g e e ! !
F F a a i i l l u u r r e e t t o o d d i i s s c c o o n n n n e e c c t t p p o o w w e e r r b b e e f f o o r r e e s s e e r r v v i i c c i i n n g g c c o o u u l l d d
r r e e s s u u l l t t i i n n d d e e a a t t h h o o r r s s e e r r i i o o u u s s i i n n j j u u r r y y . .
D D i i s s c c o o n n n n e e c c t t a a l l l l e e l l e e c c t t r r i i c c p p o o w w e e r r , , i i n n c c l l u u d d i i n n g g r r e e m m o o t t e e
d d i i s s c c o o n n n n e e c c t t s s b b e e f f o o r r e e s s e e r r v v i i c c i i n n g g . . F F o o l l l l o o w w p p r r o o p p e e r r
l l o o c c k k o o u u t t / / t t a a g g o o u u t t p p r r o o c c e e d d u u r r e e s s t t o o e e n n s s u u r r e e t t h h e e p p o o w w e e r r
c c a a n n n n o o t t b b e e i i n n a a d d v v e e r r t t e e n n t t l l y y e e n n e e r r g g i i z z e e d d . . V V e e r r i i f f y y t t h h a a t t n n o o
p p o o w w e e r r i i s s p p r r e e s s e e n n t t w w i i t t h h a a v v o o l l t t m m e e t t e e r r . .
Table 2. Troubleshooting a purge system
Diagnostic or Problem
Purge Cprsr Suction Temp Sensor
(latching diagnostic)
Purge Liquid Temp Sensor
(latching diagnostic)
Purge Carbon Tank Temp Sensor
(latching diagnostic)
Purge Liquid Level Too High (non-
latching diagnostic)
Purge Liquid Level Too High
Continuously (latching diagnostic)
Purge Carbon Regen Temp Too
Low (non-latching diagnostic)

Carbon Regeneration Temperature

Setpoint Not Satisfied (non-
latching diagnostic)
28
Cause
Bad Sensor or LLID.
Bad Sensor or LLID.
Bad Sensor or LLID.
High liquid level in purge tank or
bad level switch. The level switch
was open for at least 20 minutes.
High liquid level in purge tank or
bad level switch. The level switch
was open for more than
20 minutes, or the liquid level/
refrigeration circuit restart cycle
has occurred more than four times
in 4 hours.
The carbon tank temperature did
not increase more than 25°F
(-3.9°C) in the first 2 hours after
energizing the carbon tank heater.
The carbon tank temperature
sensor did not reach the minimum
regeneration temperature setpoint
within 4 hours after energizing the
heater.
H H o o t t S S u u r r f f a a c c e e ! !
F F a a i i l l u u r r e e t t o o f f o o l l l l o o w w i i n n s s t t r r u u c c t t i i o o n n s s b b e e l l o o w w c c o o u u l l d d r r e e s s u u l l t t i i n n
s s e e v v e e r r e e b b u u r r n n s s . .
S S u u r r f f a a c c e e t t e e m m p p e e r r a a t t u u r r e e s s m m a a y y e e x x c c e e e e d d 3 3 0 0 0 0 ° ° F F ( ( 1 1 5 5 0 0 ° ° C C ) ) . .
T T o o a a v v o o i i d d p p o o s s s s i i b b l l e e s s k k i i n n b b u u r r n n s s , , s s t t a a y y c c l l e e a a r r o o f f t t h h e e s s e e
s s u u r r f f a a c c e e s s . . I I f f p p o o s s s s i i b b l l e e , , a a l l l l o o w w s s u u r r f f a a c c e e s s t t o o c c o o o o l l b b e e f f o o r r e e
s s e e r r v v i i c c i i n n g g . . I I f f s s e e r r v v i i c c i i n n g g i i s s n n e e c c e e s s s s a a r r y y w w h h i i l l e e s s u u r r f f a a c c e e
t t e e m m p p e e r r a a t t u u r r e e s s a a r r e e s s t t i i l l l l e e l l e e v v a a t t e e d d , , y y o o u u M M U U S S T T p p u u t t o o n n
a a l l l l P P e e r r s s o o n n a a l l P P r r o o t t e e c c t t i i v v e e E E q q u u i i p p m m e e n n t t ( ( P P P P E E ) ) . .

Diagnostics

The chiller controller generates diagnostics to alert the
operator to abnormal conditions. There are two kinds
of diagnostics:
• Non-latching diagnostics: Operation continues.
Alarms resolve themselves and the alarm
disappears. They are informational only.
• Latching diagnostics: Operation stops until the
condition is corrected and the diagnostic has been
manually reset from the Tracer® AdaptiView™
display or from the Tracer® TU service tool.
The following table describes the causes of diagnostics
and operating problems that can occur with purge
systems, and suggests solutions to resolving them.
Solution
The purge refrigerant compressor suction temperature sensor has failed.
The connection has been broken or a short has occurred in the wiring, or
the LLID is not programmed or functioning correctly. Replace or repair as
required.
The purge liquid temp sensor has failed. The connection has been broken
or a short has occurred in the wiring, or the LLID is not programmed or
functioning correctly. Replace as required.
The purge carbon tank temp sensor has failed. The connection has been
broken or a short has occurred in the wiring, or the LLID is not
programmed or functioning correctly. Replace as required.
Check for restrictions in the in the vapor pick-up line and in the liquid
return line. Ensure the vapor line is sloped correctly and has no liquid
traps. Change filter drier if required. Ensure the line shutoff valves are
open.
Check for restrictions in the in the vapor pick-up line and in the liquid
return line. Ensure the vapor line is sloped correctly and has no liquid
traps. Change filter drier if required. Ensure the line shutoff valves are
open.
This diagnostic is intended to identify a failed heater or sensor. Check
carbon tank heater and heater wiring. Check the carbon tank
temperature sensor and its wiring. Check the carbon tank insulation and
the surrounding ambient temperature. Check the purge unit controls and
settings.
This is intended to identify a failing insulation system. Check carbon tank
insulation for integrity. Check ambient conditions. Check heater
operation.
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PRGD-SVX01F-EN