Trane RAUJ-C20 Installation, Operation And Maintenance Manual page 48

I I n n s s t t a a l l l l a a t t i i o o n n M M e e c c h h a a n n i i c c a a l l
Liquid Line Moisture Indicator Sight Glass
To aid in troubleshooting, install a moisture indicator
sight glass in the liquid line near the evaporator,
downstream of the solenoid valve prior to any branch
takeoffs to the expansion valve. The sight glass should
not be used to determine adequate refrigerant charge.
Liquid temperature and discharge pressure
measurements are required to determine the proper
charge. Note that under some conditions, charging
until the sight glass is solid liquid will overcharge the
system and reduce compressor reliability. See
Compressor Start-up section for proper system
charging.
Liquid Line Solenoid Valves
N N O O T T I I C C E E
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 ! !
D D o o n n o o t t u u s s e e s s o o l l e e n n o o i i d d v v a a l l v v e e a a s s a a p p u u m m p p d d o o w w n n d d e e v v i i c c e e
a a s s i i t t 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 d d a a m m a a g g e e . .
Liquid line isolation solenoid valves (one per
refrigeration circuit) are required for refrigerant
Table 12. Expansion valve selection, any BPHE all Fin and Tube OD coils (0% bleed)
Min Tonnage
1.5
2
2.5
3.5
4.5
5.5
6.5
8.5
11
13
17
20.5
30.5
45.5
(a) Valve part numbers with "-ZGA" in place of "-GA", may be used interchangeably.
Table 13. Expansion valve selection, 20 to 60 ton MCHE (30% bleed)
Min Tonnage Max Tonnage
2 3
2.5 3.5
3.5 5
4.5 7
48
Max Tonnage
2
3
4
5.5
6.5
7.5
10.5
13.5
16.5
22
26
39
59
70
Manufacturer
Sporlan
Sporlan
Sporlan
Sporlan
migration control into evaporator during "Off" cycle
and should be connected as illustrated in applicable
field connection diagram.
Thermostatic Expansion Valve (TXV)
Trane recommends a balance-ported externally
equalized valve in order to maintain satisfactory
superheat control down to lower valve loading
conditions and to compensate for pressure drops
between the expansion valve and superheat control
point (evaporator refrigerant outlet). For fin and tube
evaporator applications, a 30% bleed port TXV is
required for 20 to 60 ton units and a 15% bleed port is
required for 80 to 120 ton units.
In order to get proper refrigerant distribution into the
coil, an expansion valve is required for each coil
distributor. See tables below for valve selection.
Selection (a)
BBIZE-1-1/2-GA
BBIZE-2-GA
BBIZE-3-GA
BBIZE-4-GA
BBIZE-5-GA
BBIZE-6-GA
BBIZE-8-GA
BBIZE-12-1/2-GA
BBIZE-15-GA
OZE-20-GA
OZE-25-GA
OZE-35-GA
OZE-50-GA
OZE-60-GA
Selection (a)
ERZE-1-1/2-ZGA (BP/15)
ERZE-2-ZGA (BP/30)
ERZE-3-ZGA (BP/30)
ERZE-4-ZGA (BP/30)
Alternate (a)
ERZE-1-1/2-GA
ERZE-2-GA
ERZE-3-GA
ERZE-4-GA
ERZE-5-GA
ERZE-6-GA
ERZE-8-GA
ERZE-12-1/2-GA
ERZE-15-GA
n/a
n/a
n/a
n/a
n/a
Trane Part
VAL10487
VAL10488
VAL10489
VAL10490
SS-SVX11K-EN