PIPING INSTALLATION 
Outdoor Unit Pipe Connections
16
1. Remove service valve cover (if provided) to access
the service valves and refrigerant ports.
2.  Carefully bend and adjust length of refrigerant pipes
to meet outdoor unit service valve connections
with proper tools to avoid kinks.
3.  Add a small amount of refrigerant oil to both ends
of the flare fittings.
4. Starting with either refrigerant pipe, carefully 
center the pipe to the indoor unit connection 
port then hand tighten the flare nut.
5.  Repeat procedure with remaining pipe.
6. 
Tighten both flare nuts using a standard wrench 
and a torque wrench as shown.
7. Carefully tighten flare nuts to correct torque level referring to the Torque Table below.
Pipe Diameter Nut Size
Tightening Torque 
inch (mm) inch (mm) ft-lbs N-m
1/4 (6.35)  1/4 (17)  10 to 13  14 to 18 
3/8 (9.5)  3/8 (22)  25 to 30  34 to 42
1/2 (12.7)  1/2 (25)  36 to 45  49 to 61
5/8 (15.9)  5/8 (29)  50 to 60  68 to 82 
Copper 
piping
Oil applied 
(to reduce friction 
with the flare nut)
Flare nut
Oil applied 
(improves seal 
air-tightness)
Over tightening may damage flare connections and cause leaks.
CAUTION