Figure 14. Type UF evaporator coil with four distributors
suction line
suction line
Notes:
1. Pitch the liquid line 1 inch per 10 feet (1 cm per 3 m) so that the liquid refrigerant drains toward the indoor coil. Use
the liquid-line size recommended in
2.
Provide one expansion valve (TXV) per distributor.
TWA heat pumps only: Provide one check valve for each expansion valve.
3.
Pitch the gas line leaving the coil so that it slopes away from the coil by 1 inch per 10 feet (1 cm per 3 m).
4. Use the DETINT to prevent oil and refrigerant migration when the unit is off. The DETINT also serves to isolate the
TXV bulb from suction-header conditions. See
5.
For all coil branch circuits in the gas line, use a tube diameter that is one size smaller than the gas-line size
recommended in
6. For vertical risers, use the tube diameter recommended in the Component selection tables, found in
or
Table 3, p.
26. Ensure that the top of the riser is at least 1 foot (30 cm) above the lowest point.
7. Pitch the gas line 1 inch per 10 feet (1 cm per 3 m) toward the indoor coil.
8.
Insulate the gas line.
SS-APG008H-EN
thermal expansion
valves (TXV)
distributor
thermal expansion
valves (TXV)
distributor
Table 2, p.
Table 2, p. 25
or
Table 3, p.
Evaporator Coil
with Horizontal-Split
(Standard) Circuiting
liquid
line
sight
glass
filter drier
Evaporator Coil with
Intertwined Circuiting
liquid
line
sight
glass
filter drier
25, or
Table 3, p.
26.
"Line Sizing, Routing, and Component Selection," p.
26.
Refrigerant Piping Examples
9.
Table 2, p.
25,
23