Page 4
XP14 SERIES
STEP 2 -- REFRIGERANT PIPING
IMPORTANT !
If this unit is being matched with an approved line
set or indoor unit coil that was previously charged
with mineral oil, or if it is being matched with a coil
which was manufactured before January of 1999,
the coil and line set must be flushed prior to instal
lation. Take care to empty all existing traps. Polyol
ester (POE) oils are used in Lennox units charged
with HFC-410A refrigerant. Residual mineral oil can
act as an insulator, preventing proper heat transfer.
It can also clog the expansion device and reduce
system performance and capacity.
Failure to properly flush the system per this in
struction and the detailed Installation and Service
Procedures manual will void the warranty.
F
lush the existing line set per the following instruc
tions. For more information, refer to the Installation
and Service Procedures manual available on Dave
Net.
CAUTION -
DO NOT attempt to flush and re-use
existing line sets or indoor coil when the system con
tains
contaminants (i.e., compressor burn out).
If a new line set is being installed, size the piping per table 1.
TABLE 1
REFRIGERANT LINE SET — INCHES (MM)
Model
Valve Field Con
nections
Recommended Line Set
Liquid
Line
Vapor
Line
Liquid
Line
Vapor
Line
L15 Line Sets
-018
3/8 in.
(10 mm)
3/4 in.
(19 mm)
3/8 in.
(10 mm)
3/4 in.
(19 mm)
L15-41
15 ft. - 50 ft.
(4.6 m - 15 m)
-024
-030
-036
3/8 in.
(10 mm)
7/8 in.
(22 mm)
3/8 in.
(10 mm)
7/8 in.
(22 mm)
L15-65
15 ft. - 50 ft.
(4.6 m - 15 m)
-042
-048
-060
3/8 in.
(10 mm)
7/8 in.
(22 mm)
3/8 in.
(10 mm)
7/8 in.
(29 mm)
Field-Fabricated
NOTE -
Some applications may require a field-provided 7/8” to 1-1/8”
adapter
NOTE -
When installing refrigerant lines longer than 50
feet, refer to the Refrigerant Piping Design and Fabrica
tion Guidelines manual available on DaveNet (Corp.
9351-L9), or contact the Technical Support Department
Product Application group for assistance.
NOTE -
For new or replacement line set installation, refer
to Service and Application Note - Corp. 9112-L4 (C-91-4).
WARNING
When using a high pressure gas such as
nitrogen to pressurize a refrigeration or
air conditioning system, use a regulator
that can control the pressure down to 1 or
2 psig (6.9 to 13.8 kPa).
WARNING
Refrigerant can be harmful if it is inhaled. Refrigerant
must be used and recovered responsibly.
Failure to follow this warning may result in personal
injury or death.
WARNING
Fire, Explosion and Personal Safety Haz
ard. Failure to follow this warning could
result in damage, personal injury or
death.
Never use oxygen to pressurize or purge
refrigeration lines. Oxygen, when ex
posed to a spark or open flame, can
cause fire and/or an explosion, that could
result in property damage, personal injury
or death.
WARNING
Polyol ester (POE) oils used with HFC-410A
refrigerant absorb moisture very quickly. It is very
important that the refrigerant system be kept closed
as much as possible. DO NOT remove line set caps
or service valve stub caps until you are ready to
make connections.
IMPORTANT !
Some scroll compressors have an internal vacuum
protector that will unload scrolls when suction
pressure goes below 20 psig. A hissing sound will
be heard when the compressor is running un
loaded. Protector will reset when low pressure in
system is raised above 40 psig. DO NOT REPLACE
COMPRESSOR.
