Evp Evaporator Replacement; Water Loop; Scroll Compressor; Operational Sounds - Trane RAUJ-C20 Installation, Operation And Maintenance Manual

Normally when differential pressure reaches 5-10 psi,
the screen must be cleaned. To clean, open and flush
out until any sediment is removed.

EVP Evaporator Replacement

If the evaporator requires replacement, it is very
important that the new evaporator be replaced
correctly and with the correct refrigerant and water
piping connections. The refrigerant inlet/liquid
connection is at the bottom of the evaporator and the
refrigerant outlet/suction connection is at the top of the
evaporator and both are on the same side. Pay
particular attention to evaporators with dual circuits.
Avoid cross-circuiting when installing the new
evaporator. Proper brazing techniques for dissimilar
materials must be followed, see "Brazing Procedures"
section.

Water Loop

If the water loop is drained for an extended period, pipe
sections between the strainer and the heat exchanger
should be cleaned or replaced, to prevent rust buildup
from entering the chiller.

Scroll Compressor

Operational Sounds

The following discussion describes some of the
operational sounds of Trane R-410A scroll
compressors. These sounds do not affect the operation
or reliability of the compressor.
Shutdown
When a Scroll compressor shuts down, the gas within
the scroll expands and causes momentary reverse
rotation until the discharge check valve closes. This
results in a "flutter" type sound.
Low Ambient Start-Up
When the compressor starts up under low ambient
conditions, the initial flow rate of the compressor is low
due to the low condensing pressure. This causes a low
differential across the thermal expansion valve that
limits its capacity. Under these conditions, it is not
unusual to hear the compressor rattle until the suction
pressure climbs and the flow rate increases.
Failure Diagnosis and Replacement
The RAUJ product does not have microelectronics that
provide compressor failure diagnostic capability at the
unit level. CSHN compressors (used in 80 to 120 ton
RAUJ units) do include a module in each compressor
junction box that recognizes certain fault conditions.
Refer to Unit Description section of this manual for
protection features included with RAUJ units. For more
detailed information regarding compressor failure
diagnosis and replacement of scroll compressors, refer
to COM-SVN01*-EN.
SS-SVX11K-EN
The tables in Compressor Circuit Breakers section the
specific compressor electrical and the circuit breaker
trip information. A tripped circuit breaker does not
necessarily mean a compressor has failed, but if the
circuit breaker has not tripped the compressor is
probably good. Verify first that simpler problems don't
exist including: low pressure, high pressure, discharge
temperature, or power supply phasing and voltage
issues.
Refrigerant Evacuation and Charging
W W A A R R N N I I N N G G
R R - - 4 4 1 1 0 0 A A 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 e e r r
P P r r e e s s s s u u r r e e t t h h a a n n R R - - 2 2 2 2 ! !
F F a a i i l l u u r r e e t t o o u u s s e e p p r r o o p p e e r r e e q q u u i i p p m m e e n n t t o o r r c c o o m m p p o o n n e e n n t t s s a a s s
d d e e s s c c r r i i b b e e d d 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 e e q q u u i i p p m m e e n n t t f f a a i i l l i i n n g g
a a n n d d p p o o s s s s i i b b l l y y e e x x p p l l o o d d i i n n g g , , 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 , , 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 . .
T T h h e e u u n n i i t t s s d d e e s s c c r r i i b b e e d d i i n n t t h h i i s s m m a a n n u u a a l l u u s s e e R R - - 4 4 1 1 0 0 A A
r r e e f f r r i i g g e e r r a a n n t t w w h h i i c c h h o o p p e e r r a a t t e e s s a a t t h h i i g g h h e e r r p p r r e e s s s s u u r r e e s s
t t h h a a n n R R - - 2 2 2 2 . . U U s s e e O O N N L L Y Y R R - - 4 4 1 1 0 0 A A r r a a t t e e d d s s e e r r v v i i c c e e
e e q q u u i i p p m m e e n n t t o o r r c c o o m m p p o o n n e e n n t t s s w w i i t t h h t t h h e e s s e e u u n n i i t t s s . . F F o o r r
s s p p e e c c i i f f i i c c h h a a n n d d l l i i n n g g c c o o n n c c e e r r n n s s w w i i t t h h R R - - 4 4 1 1 0 0 A A , , p p l l e e a a s s e e
c c o o n n t t a a c c t t y y o o u u r r l l o o c c a a l l T T r r a a n n e e r r e e p p r r e e s s e e n n t t a a t t i i v v e e . .
W W A A R R N N I I N N G G
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 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 . .
The compressor manifold system was designed to
provide proper oil return to each compressor. The
refrigerant manifold must not be modified in any way.
Should a compressor replacement become necessary
and a suction line filter drier is to be installed, install it
at least the minimum distance upstream of the suction
manifold tee as shown in illustrations shown in Suction
Line Filter section. See SS-APG012-EN for
recommended suction filter selections.
N N O O T T I I C C E E
C C o o m m p p r r e e s s s s o o r r D D a a m m a a g g e e ! !
A A l l t t e e r r i i n n g g t t h h e e m m a a n n i i f f o o l l d d p p i i p p i i n n g g c c o o u u l l d d c c a a u u s s e e o o i i l l r r e e t t u u r r n n
p p r r o o b b l l e e m m s s a a n n d d c c o o m m p p r r e e s s s s o o r r f f a a i i l l u u r r e e . .
D D o o n n o o t t a a l l t t e e r r c c o o m m p p r r e e s s s s o o r r m m a a n n i i f f o o l l d d p p i i p p i i n n g g . .
M M a a i i n n t t e e n n a a n n c c e e
121