Preliminary Expansion Valve; Adjustment - Trane RAUJ-C20 Installation, Operation And Maintenance Manual

Preliminary Expansion Valve

Adjustment

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 ! !
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 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
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 o o r r r r e e d d u u c c e e d d c c o o m m p p r r e e s s s s o o r r l l i i f f e e . .
I I n n c c r r e e a a s s e e t t h h e e r r m m a a l l e e x x p p a a n n s s i i o o n n v v a a l l v v e e s s u u p p e e r r h h e e a a t t
s s e e t t t t i i n n g g s s b b e e f f o o r r e e s s t t a a r r t t i i n n g g c c o o m m p p r r e e s s s s o o r r s s t t o o m m i i n n i i m m i i z z e e
c c o o m m p p r r e e s s s s o o r r o o p p e e r r a a t t i i o o n n w w i i t t h h l l o o w w o o i i l l v v i i s s c c o o s s i i t t y y . .
No bleed thermal expansion valves are set by
manufacturers to control between 12-14.4°F superheat
Table 30. Thermal expansion valve manufacturer settings - no bleed — Sporlan
Standard off the shelf nominal valve settings (90 PSIG air test setting)
Superheat,
Valve
BBIZE-1-GA
BBIZE-1-1/2-GA
BBIZE-2-GA
BBIZE-3-GA
BBIZE-4-GA
BBIZE-5-GA
BBIZE-6-GA
BBIZE-8-GA
BBIZE-12.5-GA
BBIZE-15-GA
OZE-20-GA
OZE-25-GA
OZE-35-GA
OZE-50-GA
OZE-60-GA
Table 31. Thermal expansion valve manufacturer settings - no bleed — Emerson
Standard off the shelf nominal valve settings
Valve Nom Tons
1-1/2 to 7
C
TF 12 to 20
SS-SVX11K-EN
CW turns
°F available
4.5
12
7.5
Super-
CW turns
heat, °F
available
6
13
5
leaving the evaporator at nominal design conditions.
Thermal expansion valves with bleeds are set to their
highest superheat setting. Actual superheat depends
on many factors (valve vs. system relative sizing,
operating conditions, system load step, system charge,
piping, and condenser fan control). The thermal
expansion valves must be adjusted as part of the unit
start-up procedure. Do not adjust valves beyond
manufacturer's available nominal adjustment range.
N N o o t t e e : : In tables below, valve part numbers with "-ZGA"
in place of "-GA", may be used interchangeably.
"ERZE-" part number valves are an acceptable
alternate to "BBIZE" valves.
Superheat
CCW turns change per
available turn
2.4°F
4.5
3.4°F
1.8°F
Superheat
CCW turns change per
available
6
5
Field adjust
for 18°F (DX Field adjust for
evap coil) 15°F (EVP only)
2.5 CW
.25 CW
3.25 CW
Field adjust
for 18°F (DX
evap coil)
turn
4 1.25 CW
2 2.5 CW
S S t t a a r r t t - - U U p p
—
.25 CW
1.75 CW
Field adjust
for 15°F
(EVP only)
1.0 CW
107