Figure C
Fig.
7
-2
16
7.6 LINE INSULATION
Only refrigeration-grade copper piping (dehydrated and sealed) should be used.
Take extreme care to
Refrigerant piping should be as short as possible, with a minimum of elbows or bends, to avoid capacity
allow the strapping to directly contact the tubing. Use a closed cell insulation to separate the strapping
from the tubing. Do not kink or twist the tubing.
Refrigerant piping should not be installed in a cement slab, as this limits access to the refrigerant should
a leak be suspected.
Note: To ensure good oil return to the compressor, it is important to pitch the horizontal suction
line toward the compressor, approximately 1/2" for every 10' of line
.
keep the refrigerant tubing clean and dry prior to and during installation
. If there is any doubt on the
loss and increased operating costs.
cleaness of the piping, blow out th
e line with dry nitrogen to remove any chips or debris before connection
Refrigerant lines must be adequately supported. If metal strapping is used to secure the tubing, do not
are made. Always keep tubing sealed
until the connections are to be made.
.
In severe applications (hot, high humidity areas) greater thickness may be required. Apply the suction line
Suction line must be insulated in order to prevent condensation from forming on the piping and to reduce
insulation by sliding it on the sealed tubing before cutting and making connections
heat gain from the surrounding air. Generally 3/8" wall thickness of Armaflex or equivalent is satisfactory.
.
Refrigerant Line Sizing
unit size and the maximum refrigerant line length
.
such as kitchens, boiler rooms, hot attics or on the roof, then, they should be insulated as well.
Liquid lines do not necessarily need insulation, however, if they are run in high ambient spaces
Make sure to use proper size copper tubing for the liquid line to prevent liquid refrigerant flashing.
Keep the vapor line and liquid line seperated. To prevent an undesirable heat transfer and capacity
loss.
Check the following table (
Table 7-1
) for correct suction and liquid line sizes for any combination of the
Central Air Conditioner
Model: Cooling Only,
13
SEER
units
