Install The Connecting Pipe - Lennox COMFORT Installation Manual

7. INSTALL THE CONNECTING PIPE

(1) Maximum pipe length
Model
(12-18)/(24-48)
(2) Piping sizes
Model
12-18
24/30
36-48
CAUTIONS
• Do not let air, dust, or other impurities fall in the pipe system during the time of installation.
• The connecting pipe should not be installed until the indoor and outdoor units have been fixed already.
• Keep the connecting pipe dry, and do not let moisture in during installation.
The Procedure of Connecting Pipes
1. Measure the necessary length of the connecting pipe, and make it by the following way.
(Refer to "Connect The Pipes" for details)
1) Connect the indoor unit at first, then the outdoor unit.
• Bend the tubing in proper way. Do not harm to them.
CAUTION
• Daub the surfaces of the flare pipe and the joint nuts with frozen oil, and wrench it for 3~4 rounds
with hands before fasten the flare nuts. (Refer to chart 19)
• Be sure to use two wrenches simultaneously when you connect or disconnect the pipes.
2) The stop value of the outdoor unit should be closed absolutely (as original state). Every time you
connect it, first loosen the nuts at the part of stop value, then connect the flare pipe immediately (in
5 minutes). If the nuts have been loosened for a long time, dusts and other impurities may enter the
pipe system and may cause malfunction later. So please expel the air out of the pipe with refrigerant
before connection.
3) Expel the air (refer to the "Expel The Air") after connecting the refrigerant pipe with the indoor unit.
Then fasten the nuts at the repair-points.
Notices For Bendable Pipe
• The bending angle should not exceed 90.
• Bending position is preferably in the middle of the bendable pipe. The larger the bending radius the
better it is.
• Do not bend the pipe more than three times.
Max. Length
25/30m
Liquid (mm/inch)
6.35 (1/4)
9.52 (3/8)
12.7 (1/2)
13
Max. Elevation
15/20m
Gas (mm/inch)
12.7 (1/2)
16.0 (5/8)
19.0 (3/4)