Giatsu GIA-CEN-10KOMP Manuel D'installation page 32

Outdoor unit (set)
4.8 Remove foreign materials in the pipeline.
1) The foreign materials, which enter the refrigerant pipe during installation, shall be cleaned with high pressure nitrogen.
2) Don't connect with the indoor unit upon cleaning.
3) Use the nitrogen instead of refrigerant or flammable toxic gases like oxygen.
4.9 Air tightness test
1) After the refrigerant pipe is installed and connected to the indoor unit, and before the connecting pipes between the indoor and outdoor
units are connected to the valves of the outdoor units, refill the nitrogen with the pressure of 40kgf/cm² (4.0MPa) from the gas side and
the fluid side simultaneously, mark the pressure value, and then perform 24-hour air tightness test.
2) If the pressure drops, recheck the leakage of all interfaces and then maintain the pressure for 24 hours.
3) Don't connect with the outdoor unit during maintaining the pressure.
4.10Vacuumizing
1) The vacuum pump has the vacuum degree of less than -0.1MPa and the air displacement of more than 40L/min.
2) It is unnecessary to vacuumize the outdoor unit. Don't open the check valves at the gas side and the liquid side of the outdoor unit.
3) Make sure the vacuum pump can drop up to -0.1MPa within 2 hours; if it fails to drop up to -0.1MPa after 3 hours, check moisture or air
leak.
4) The vacuum pump must have a check valve.
After dropping up to -0.1MPa, the vacuum pump keeps on running for 20-60 minutes.
!
NOTE
· Don't use tools and measuring apparatus using in different refrigerants or directly contacting the refrigerant.
· Don't exhaust air with refrigerant gas.
· If the vacuum degree cannot reach -0.1MPa, recheck its leakage. If not, keep the vacuum pump on for 1-2h.
30m
High pressure liquid pipe
Low pressure gas pipe
Oil return bend
Fig. 4-8 Position of Oil Return Bend at the Horizontal Direction
Connect the vacuum pump
Run the vacuum pump (above 2 hours)
Stop the vacuum pump
Remain vacuum (above 1h)
60m
Indoor unit (set)
1. Close the valve of the pressure gauge;
2. Disconnect the pressure gauge and the
vacuum pump;
3. Close the vacuum pump.
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