Accorroni CHIP MONO DC INVERTER 2500W Mode D'emploi page 40

Air purging
Air and moisture in the refrigerant system have undesirable effects as indicated below:
● Pressure in the system rises.
Indoor unit
● Operating current rises.
● Cooling or heating efficiency drops.
Outdoor unit
● Moisture in the refrigerant circuit may freeze and block capillary tubing.
● Water may lead to corrosion of parts in the refrigeration system.
Therefore, the indoor unit and tubing between the indoor and outdoor unit must be
leak tested and evacuated to remove any non-condensable and moisture from the
system. Manifold gauge
Air purging with vacuum pump
Pressure
gauge
● Preparation
Check that each tube (both liquid and gas side tubes) between the indoor and
Charge hose
outdoor units have been properly connected and all wiring for the test run has been
completed. Remove the service valve caps from both the gas and the liquid side on
Nitrogen gas cylinder
the outdoor unit.
(in vertical position)
Note that both the liquid and the gas side service valves on the outdoor unit are kept
closed at this stage.
● Pipe length and refrigerant amount:
Indoor unit
● When relocate the unit to another place, perform evacuation using vacuum pump.
Make sure the refrigerant added into the air conditioner is liquid form in any case.
Outdoor unit
Caution in handling the packed valve
● Open the valve stem until it hits against the stopper. Do not try to open it further.
● Securely tighten the valve stem cap with a spanner or the like.
● Valve stem cap tightening torque (See Tightening torque table in previous page).
When Using the Vacuum Pump
Manifold gauge
(For method of using a manifold valve, refer to its operation manual.)
Pressure
1. Completely tighten the flare nuts, A, B, C, D, connect the manifold valve charge
gauge
hose to a charge port of the low-pressure valve on the gas pipe side.
Close
Open
2. Connect the charge hose connection to the vacuum pump.
3. Fully open the handle Lo of the manifold valve.
4. Operate the vacuum pump to evacuate. After starting evacuation, slightly loose
Vacuum pump
the flare nut of the Lo valve on the gas pipe side and check that the air is entering
(Operation noise of the vacuum pump changes and a compound meter indicates 0
instead of minus)
5. After the evacuation is complete, fully close the handle Lo of the manifold valve and
stop the operation of the vacuum pump. Make evacuation for 15 minutes or more and
check that the compound meter indicates -76cmHg (1x105Pa).
6. Turn the stem of the packed valve B about 45° counter clockwise for 6-7 seconds
after the gas coming out, and then tighten the flare nut again. Make sure the pressure
display in the pressure indicator is a little higher than the atmosphere pressure.
7. Remove the charge hose from the Low pressure charge hose.
8. Fully open the packed valve stems B and A.
9. Securely tighten the cap of the packed valve.
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