Be sure to use a vacuum pump with a backflow protection function, so that oil inside the pump does not flow back into the air conditioner tubes when the pump stops.
(If the oil inside the vacuum pump enters the air conditioner that adopts the R410A, it may cause problems in the refrigeration cycle).
(1) Connect the crank valve charge hose to the service port on the gas side of the valve.
(2) Connect the charging hose to the vacuum pump port.
(3) Fully open the crank on the low pressure side of the valve.
(4) Operate the vacuum pump to initiate evacuation.
Perform the evacuation for about 35 minutes if the total length of the pipe is 70 meters. (25 minutes to 50 meters) (assuming a pump capacity of 27 liters per minute.) Then confirm that the compound pressure gauge reading is 101kPa (- 76 cmHg).
(5) Close the crank on the low pressure side of the valve.
(6) Open the valve stem (on both lines: Gas and Liquid).
(7) Remove the charge hose from the service port.
(8) Securely tighten the cap on each valve.
