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Refrigerant Lines Connection, Evacuating and Charging
Refrigerant Lines Preparation &
Connection
The refrigerant lines should be kept sealed until ready to be
connected. Follow the following steps to insure a quality leak
proof installation:
Step 1. Refrigerant Line Connection
Carefully bend and cut the tubing to prepare for flaring. Use a
flaring tool designed for R410a, following the recommended
manufacturer’s procedure. Tighten the flare nut to the
indicated torque by using a spanner wrench and a toque
wrench. Connect the indoor unit first, then the outdoor unit.
Use the 3/8” to 1/2” flare adapter if needed.
Note:
Over tightening flare nuts may damage flare connections and
may cause leaks.
Tubing Size
Torque (foot-pounds) Torque (inch-pounds)
1/4”
10-13
124-159
3/8”
25-31
301-372
1/2”
36-45
434-540
5/8”
50-60
602-726
Step 2. System Leak Check
Refrigerant lines should be pressurized prior to evacuating
system to check for leaks.
Use only dry nitrogen with a pressure regulator for
pressurizing unit. Pressurize with 150 psi of dry nitrogen.
Apply soap and water to check whether the joints are leaky. A
leak detector may also be used for a leakage test.
Hint:
You may want to perform leak testing and evacuation before
wiring to save time, electrical connections can be completed
while your vacuum pump is running.
Step 3. System Evacuation
Note: The outdoor unit contains a refrigerant charge, leave
liquid and gas valves closed.
1. After no leaks have been detected, connect a vacuum
pump to the outdoor unit.
2. Connect appropriate hoses to manifold gauge, vacuum
pump and unit refrigeration connections.
3.
Evacuate the system until the micron gauge reads no
higher than 350 microns.
4. Close valve to vacuum pump; if pressure does not rise
above 500 microns after one minute, the evacuation
should be complete.
5.
If it does rise, check for leaks and/or evacuate longer.
6.
For refrigerant lines longer than 25 feet, refer to
installation instructions chart included with the unit
installation manual for additional charge.
