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11.3.2.3 Connecting the piping to outdoor multi
Decide piping length and then cut by using pipe cutter. Remove burrs from cut edge.
Make flare after inserting the flare nut (locate at valve) onto the copper pipe.
Align center of piping to valve and then tighten with torque wrench to the specified torque as stated in the table.
11.3.2.4 Gas Leak Checking
Pressure test to system to 400 PSIG with dry nitrogen, in stages. Thoroughly leak check the system.
If the pressure holds, release the nitrogen and proceed to section 11.3.3.
11.3.3 Evacuation of the equipment
WHEN INSTALLING AN AIR CONDITIONER, BE SURE TO EVACUATE THE AIR INSIDE THE INDOOR UNIT AND
PIPES in the following procedures.
1. Connect a charging hose with a push pin to the Low side of a charging set and the service port of the 3-way
valve.
2. Connect the micron gauge between vacuum pump and service port of outdoor units.
3. Turn on the power switch of the vacuum pump and make sure that connect digital micron gauge and to pull
down to a value of 500 microns.
4. To make sure micron gauge a value 500 microns and close the low side valve of the charging set and turn off
the vacuum pump.
5. Disconnect the vacuum pump house from the service port of the 3-way valve.
6. Tighten the service port caps of the 3-way valve at a torque of 13.3 Ibf.ft with a torque wrench.
7. Remove the valve caps of both of the 2-way valve and 3-way valve. Position both of the valves to “Open”
using a hexagonal wrench (5/32").