IO-123084-GAW-063017
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©2017 AirMark
Clean coil fins with degreasing agent or mild
detergent and rinse fins clean prior to installation.
All connection joints should be burr-free and clean.
Not removing burrs and cleaning may increase
chances of a leak. It is recommended to use a
pipe cutter to remove the spun closed end of the
suction line.
To avoid damage to grommets (where present),
remove these prior to brazing by sliding over the
lines. Use a quenching cloth or allow the lines to
cool before reinstalling the grommets.
CAUTION
Some Airmark coils may include a
Schrader valve on the suction manifold. Ensure
that the Schrader valve and valve core (where
present) are protected from heat during brazing
and installation to prevent leakage.
Metering Device
Airmark coils are available with two kinds of
metering devices a) flowrator or b) TXV.
Instructions below are separated in sections
according to the metering device. Ensure that the
applicable section is thoroughly read and
understood.
Flowrator Coils:
PISTON
DISTRIBUTOR
TAIL PIECE
13/16" NUT
TEFLON O-RING
Fig.3. Flowrator assy components
CAUTION
Use Piston sizes recommended
by the outdoor unit manufacturer whenever
possible. The piston should be sized according to
the capacity of the outdoor unit.
WARNING
Failure to install the proper piston
can lead to poor system performance and possible
compressor damage.
During some installations a piston change may be
required. If so the installer
MUST
change the
piston. As stated earlier, use piston sizes
recommended by the outdoor unit manufacturer. If
a sizing chart is not available, use Table 1 below
to size the required piston. The size of the piston
is stamped on the piston body.
Table.1. Piston Size Chart
Instruction for piston change
1) Turn the 13/16 nut once to release any
residual pressure in the coil.
2) After ensuring that the coil is free of any
residual pressure, disassemble the
flowrator body completely using two
wrenches. Distortion of the feeder tubes
SHOULD be avoided.
3) The wrench used to clasp the nut should
be turned in a counter-clockwise direction
to unscrew the nut.
4) Slide the 13/16 nut over the line set and
separate the two halves of the flowrator.
CAUTION
Pay close attention to the Teflon
O-ring. Be sure to replace the O-ring to attain a
proper seal. (The Teflon O-ring is located between
the two halves of the flowrator)
5) Pull the piston out using a small wire or
pick. Verify the piston size (size is typically
stamped on the body of the piston). If a
different piston size is required by the
outdoor unit manufacturer replace the
piston using the small wire provided with
the piston kit.
Outdoor
Capacity
Orifice
Size–R22
Orifice
Size-R410A
12,000
0.041
N/A
18,000
0.055
0.049
24,000
0.059
0.055
30,000
0.068
0.059
36,000
0.074
0.068
42,000
0.080
0.074
48,000
0.084
0.080
60,000
0.092
0.089
