Trane Climate Changer TCFS Nstallation, Operation, And Maintenance page 46

Piping and Connections
Figure 54. Single-circuit condensing unit: evaporator coil with two distributors
Evaporator Coil with Horizontal-Split
Suction line
Evaporator Coil with Intertwined Circuiting
Suction line
46
(Standard) Circuiting
"Trim"
solenoid valve
Sight
Thermal
glass
expansion
valve (TXV)
"Pump-down"
solenoid valve
Distributor
Sight
glass
Solenoid
Thermal
expansion
valve (TXV)
Distributor
1. Pitch the liquid line slightly—1 inch/10 feet —so
the refrigerant drains toward the evaporator.
2. Provide one expansion valve per distributor.
3. Slightly pitch the outlet line from the suction
Liquid
header toward the suction riser— 1 inch/10 feet
line
in the direction of flow. Use the tube diameter
that matches the suction-header connection.
Use a double-elbow configuration to isolate the
TXV bulb from other suction headers.
4. This looks like a trap, but is actually due to the
Filter drier
requirement that the refrigerant gas leaving the
coil flows downward, past the lowest suction-
header outlet, before turning upward.
5. Use the "horizontal" tube diameter as specified
in the condensing unit application manual.
6. Use the tube diameter recommended for a
vertical rise as specified in the condensing unit
application manual. Assure the top of the riser is
Liquid
higher than the evaporator coil.
line
7. Pitch the suction line slightly—1 inch/10 feet —
so that the refrigerant drains toward the
evaporator.
8. Insulate the suction line.
Filter drier
valve
9. Only use a "trim" solenoid valve for constant-
volume, humidity-sensitive applications. For all
other applications, install a single solenoid valve
(the "pumpdown" solenoid valve) between the
liquid-line filter drier and the sight glass.
Note: Due to reduced coil volume in condensing
units with microchannel heat exchanger
condenser, do not use trim solenoid valves
for these units.
CLCH-SVX010A-EN