Unique CU Series, Service Manual And Spare Parts List

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7.9.2 Flaring and Connecting
•
Remove the protecting cap from the flare fitting.
•
Remove the protecting cap from the tubing and cut to the required length. Make sure
that the cut is perpendicular and clean, without burrs.
•
Slip the flare nut on the tubing and flare the tube end, using standard flaring tools.
•
Tighten the nut until resistance is met. Using a suitable wrench, tighten an additional
1/4 turn. Use the following specified torque, according to connection size. See
illustration in Fig.7-9.
•
The valves on the outdoor unit must remain closed until all four connections have
been made.
Fig. 7-9
7.9.3 Air Vacuum and Refrigerant Charge
When all the fittings are connected, air must be purged as follows:
•
Open the service port cap on the suction line valve (large valve).
•
Connect the vacuum pump to the service port via the pressure gauge and operate the
pump for 30 minutes.
•
Make sure that full vacuum is reached and disconnect the vacuum pump.
•
Open the liquid line valve (small valve) with an Allen-Wrench for the purpose.
•
Open the suction line valve (large valve) using an Allen-Wrench for the purpose.
•
The outdoor unit is supplied with sufficient refrigerant for 10 meters tubing. Add
refrigerant and oil according to the table, for each meter of tubing above 10 meters. If
the tubing is shorter than 10 meters, release gas from the system through the service
valve into a recycling device.
•
Close the service port caps on the suction line and the liquid valves.
•
Make sure that the valves are properly opened. Be careful not to open them more than
required, as this may damage the thread.
•
Replace the stem cap. Oil the cap beam and hand tighten the cap, until resistance is
met. Use a suitable wrench to tighten the cap by an additional 1/6 turn.
•
Check the system for refrigerant leaks using a leak detector.
Tubing Size 3/8" 1/2" 5/8" 3/4" 7/8"
Torque
Kgm
4 5 6 8 10