4. Braze the liquid line to the evaporator liquid connection. Nitrogen should be flowing
through the evaporator coil.
5. Slide the plastic cap away from the suction connection at the indoor coil. Braze the
suction line to the evaporator suction connection. Refer to the Table 1 for proper
suction line sizing.
6. Protect the suction valve with a wet rag and braze the suction line connection to the
outdoor unit. The nitrogen flow should be exiting the system from the suction service
port connection. After this connection has cooled, remove the nitrogen source from
the liquid fitting service port.
7. Replace the Schrader core in the liquid and suction valves.
8. Leak test all refrigerant piping connections including the service port flare caps to be
sure they are leak tight.
DO NOT OVER TIGHTEN (between 40 and 60 inch -lbs.
maximum).
9. Evacuate the suction line, evaporator, and the liquid line, to 350 microns or less.
Table 1: Recommended Liquid and Suction Tube Diameters (ln.)
MODEL
SIZE
LIQUID
SUCTION
Tube Diameter
Tube Diameter
24
3/8
3/4
36
3/8
3/4
48
3/8
60
3/8
7/8
12
7/8
10. Replace cap on service ports. Do not remove the flare caps from the service ports
except when necessary for servicing the system.
11. Release the refrigerant charge into the system. Open both the liquid and suction
valves by removing the plunger cap and with an hex wrench back out counter
-clockwise until valve stem just touches the chamfered retaining wall.
12. Replace plunger cap finger tight, then tighten an additional 1/12 turn (1/2 hex flat).
Cap must be replaced to prevent leaks.
WARNING
Never attempt to repair any brazed connections while the system is under pres-
sure. Personal injury could result.
See "System Charge" section for checking and recording system charge.
4.0 INTERCONNECTING TUBING
4.1 SUCTION AND LIQUID LINES
Keep all lines sealed until connection is made.
Make connections at the indoor coil first.
Refer to Li ne Size Information in Ta bles 2 and 3 for correct size and multipliers to be
used to determine capacity for various suction line diameters and lengths of run. The
losses due to the lines being exposed to outdoor conditions are not included.
The factory refrigerant charge in the outdoor unit is sufficient for 15 feet of standard
size interconnecting liquid line. Calculate actual charge required with installed liquid
line size and length as below.
5/16” ± .4 oz. per foot
3/8” ± .6 oz . per foot
1/2” ± 1.2 oz . per foot
