3
To avoid possible explosion, use only returnable (not
disposable) service cylinders when removing refrigerant
from a system.
•
Ensure the cylinder is free of damage which could lead to
a leak or explosion.
•
Ensure the hydrostatic test date does not exceed 5 years.
•
Ensure the pressure rating meets or exceeds 400 PSIG.
When in doubt, do not use cylinder.
Refrigerant Lines
The compressor POE oil for R-410A units is extremely
susceptible to moisture absorption and could cause
compressor failure. Do not leave system open to atmos-
phere any longer than necessary for installation.
CAUTION
Use only refrigerant grade (dehydrated and sealed) copper tub-
ing to connect the condensing unit with the indoor evaporator.
After cutting the tubing, install plugs to keep refrigerant tubing
clean and dry prior to and during installation. Tubing should
always be cut square keeping ends round and free from burrs.
Clean the tubing to prevent contamination.
Do NOT let refrigerant lines come in direct contact with plumb-
ing, ductwork, floor joists, wall studs, floors, and walls. When
running refrigerant lines through a foundation or wall, openings
should allow for sound and vibration absorbing material to be
placed or installed between tubing and foundation. Any gap
between foundation or wall and refrigerant lines should be filled
with a pliable silicon-based caulk, RTV or a vibration damping
material. Avoid suspending refrigerant tubing from joists and
studs with rigid wire or straps that would come in contact with
the tubing. Use an insulated or suspension type hanger. Keep
both lines separate and always insulate the suction line.
These sizes are recommended for line lengths of 79 feet or
less to obtain optimum performance. For alternate line siz-
ing options or runs of more than 79 feet, refer to TP-107
Long Line Set Application R-410A, or contact your distribu-
tor for assistance.
Cond
Unit
Tons
Suct
Liq
Suct
Liq
Suct
Liq
1 1/2
5/8
1/4
3/4
3/8
3/4
3/8
2
5/8
1/4
3/4
3/8
3/4
3/8
2 1/2
5/8
1/4
3/4
3/8
7/8
3/8
3
3/4
3/8
7/8
3/8
1 1/8
3/8
3 1/2
7/8
3/8
1 1/8
3/8
1 1/8
3/8
4
7/8
3/8
1 1/8
3/8
1 1/8
3/8
5
7/8
3/8
1 1/8
3/8
1 1/8
3/8
Line Diameter (In. OD)
RECOMMENDED INTERCONNECTING TUBING (Ft)
0-24
25-49
50-79*
* Lines greater than 79 feet in length or vertical elevation changes more
than 50 feet
refer to the TP-107 R-410A Long Line Set Application
Guidelines or contact your distributor for assistance.
Insulation is necessary to prevent condensation from forming
and dropping from the suction line. Armflex (or satisfactory
equivalent) with 3/8
”
min. wall thickness is recommended. In
severe conditions (hot, high humidity areas) 1/2
”
insulation may
be required. Insulation must be installed in a manner which
protects tubing from damage and contamination.
Existing Line Sets
Where possible, drain as much residual compressor oil from
existing systems, lines, and traps; pay close attention to low
areas where oil may collect. Use of an approved flushing agent
is recommended followed by a nitrogen purge to remove any
remaining flushing agent from the lines or indoor coil. Replace-
ment of indoor coil is recommended.
NOTE:
If using existing indoor coil and changing refrigerant
types, ensure the indoor coil and metering device are compat-
ible with the type of refrigerant being used. If new indoor coil is
required check spec sheet or AHRI for approved coil. If system
is being replaced due to compressor electrical failure, assume
acid is in system. Refer to Service Procedure S-115 Compres-
sor Burnout in service manual for clean-up procedure.
Burying Refrigerant Lines
If burying refrigerant lines can not be avoided, use the following
checklist.
1. Insulate liquid and suction lines separately.
2. Enclose all underground portions of the refrigerant lines
in waterproof material (conduit or pipe) sealing the ends
where tubing enters/exits the enclosure.
3. If the lines must pass under or through a concrete slab,
ensure lines are adequately protected and sealed.