Refrigerant Piping; Line Insulation - Haier HR18D2VAR Service Manual

8.5 REFRIGERANT PIPING

Properly sized and installed refrigerant piping is very important for the efficient operation of the air
conditioning system.
Note the following guidelines
1. The total run, both vertical and horizontal, should be less than 50 feet or line size correction may
be necessary.
2. If the vertical separation exceeds 10 feet use the next larger liquid line size .
Only refrigeration-grade copper piping (dehydrated and sealed) should be used. Take extreme care to
keep the refrigerant tubing clean and dry prior to and during installation. If there is any doubt on the
cleaness of the piping, blow out the line with dry nitrogen to remove any chips or debris before connection
are made. Always keep tubing sealed until the connections are to be made.
Refrigerant piping should be as short as possible, with a minimum of elbows or bends, to avoid capacity
loss and increased operating costs.
Refrigerant lines must be adequately supported. If metal strapping is used to secure the tubing, do not
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 .

8.6 Line Insulation

Suction line must be insulated in order to prevent condensation from forming on the piping and to reduce
heat gain from the surrounding air. Generally 3/8" wall thickness of Armaflex or equivalent is satisfactory.
In severe applications (hot, high humidity areas) greater thickness may be required. Apply the suction line
insulation by sliding it on the sealed tubing before cutting and making connections
17
Central Air Conditioning
:
Figure A
Figure C
Fig. 8-2
Model: Heat Pump, HR13-D2
WHEN INDOOR UNIT IS 4 FEET OR
MORE BELOW OUTDOOR UNIT, A
SUCTION LINE OIL TRAP IS REQUIRED.
PROVDE ADDITIONAL TRAPS FOR
EVERY 20 FEET OF LIFT.
Figure B
.