Hisense Group KFR-3208GW Appendix Installation, Fig.A, knob of the manifold valve must, Fig.B

Appendix: Installation

5.Air purging

Air and moisture remaining in the refrigerant system have undesirable effects as indicated below. Therefore, they must be purged completely.

pressure in the system rises

operating current rises

cooling efficiency drops

moisture in the air may freeze and block capillary tubing

water may lead to corrosion of parts in the refrigerant system

Air Purging with a Vacuum Pump (for Test Run)

Indoor unit

Outdoor unit Pressure

gauge

Lo Hi Manifold valve

(1)Check that each tube (both narrow and wide tubes between the indoor and outdoor units have been properly connected and all wiring for the test run has been completed. Note that both narrow and wide tube service valves on the outdoor unit are kept closed at this stage.

(2)Using an adjustable wrench or box wrench, remove the valve caps from the service valve on both narrow and wide tubes.

(3)Connect a vacuum pump and a manifold valve (with pressure gauges) to the service port on the wide tube service valve.(Fig.A)

Be sure to use a manifold valve for air purging. If it is not available, use a stop valve for this purpose. The ¡°Hi¡±

90 (1/4 turn)

Vacuum pump

Fig.A

Narrow tube

Hex wrench

Wide tube

knob of the manifold valve must

CAUTION always be kept closed.

(4)With the ¡°Lo¡±knob of the manifold valve open, run the vacuum pump. The operation time for the vacuum pump varies with tubing length and the capacity of the pump. The following table shows the amount of time for evacuation:

Table

Required time for evacuation when capacity

of 100 liter/h vacuum pump is used

If tubing length is less than 10 m	If tubing length is more than 10 m
10 min. or more	15 min. or more

NOTE

The required time in the above table is calculated based on the assumption that the ideal (or target) vacuum condition is around 10 mmHg abs.

(5) With the vacuum pump still running, close the Lo knob of the manifold valve. Then stop the vacuum pump.

(6)With the accessory hex wrench, turn the valve stem on the narrow tube service valve counterclockwise by 90 degrees (1/4 turn) for 10 seconds, and then turn the stem clockwise to close it again. (Fig.B)

Be sure to completely insert the hex wrench before attempting to turn the

valve.

CAUTION

23

Valve cap

Vacuum hose to manifold valve

Fig.B

(7)Leak test all joints at the tubing (both indoor and outdoors) with liquid soap. Bubbles indicate a leak. Be sure to wipe off the soap with a clean cloth.

(8)With the hex wrench, turn the wide tube service valve stem counter-clockwise to fully open the valve.

(9)Turn the narrow tube service valve stem counter-clockwise to fully open the valve.

(10)Loosen the vacuum hose connected to the wide tube service port slightly to release the pressure. Then, remove the hose.

(11)Replace the bonnet and flare nut on the wide tube service port and fasten the flare nut securely with an adjustable wrench or box wrench. Next, mount the valve cap and tighten it with a torque wrench (the cap needs to be tightened with the torque of 200kg-cm). This process is very important to prevent gas from leaking from the system.

(12)Test run the air conditioner.

(13)While the air conditioner is running, apply liquid soap to check for any gas leaks around the service valves or caps.

(14)If there is no leakage, stop the air conditioner. (15)Wipe off the soap on the tubing.

This completes air purging with a vacuum pump and the air conditioner is ready for actual operation.

6.Please contact the technical service for further information.