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13.6.6 Re-insertion of refrigerant in service
When re-insertion is needed, follow the procedures to ensure the insertion of new refrigerant at correct amount.
1. Attach charging hose (blue) to the service port of the outdoor unit.
2. Attach charging hose (red) to the vacuum pump. Fully open the 2-way and 3-way valves.
3. Place the refrigerant cylinder on the digital scale for refrigerant charging and connect the charge hose (yellow) to
the connection port of the vacuum pump and the digital scale. Leave the cylinder valve fully open.
4. Fully open the handles Lo and Hi of the manifold gauge, and switch on the vacuum pump, and then perform
evacuation for at or more than one hour.
5. Confirm the compound gauge of -0.1 MPa (-76cmHg) and fully open the handles of Lo and Hi, and switch off the
vacuum pump. Leave it for about 1 ~ 2 minutes and confirm the needle of the compound gauge does not turn
back.
Refer to the picture below to follow the procedures below.
6. Remove the charging hose (red) of the manifold gauge from the vacuum pump adopter.
7. After adjusting the digital scale to zero, open the cylinder valve and the valve Lo of the manifold gauge, and
insert the refrigerant.
8. If it is not possible to insert the refrigerant at regulated amount at once, operate the cooling mode and gradually
insert the refrigerant (recommended amount approx. 150 g / 1 time)
*Do not insert much refrigerant at once.
9. Close the open/close valve and insert the refrigerant in the charging hose to the outdoor unit.
*Perform this procedure during operating cooling operation. Close the stem of the two-way valve, and when the
pressure of the manifold gauge becomes zero (0), quickly remove the charging hose (blue). Immediately open
the 2-way valve, and stop the cooling operation.
10. Final checking • • • Confirm the 2-way and 3-way valves are fully open.
Attach the caps of the service port and control valve, and then check the gas leakage around the caps.
(Liquid side)
(Indoor unit)
(Outdoor unit)
(Gas side)
Two-way
valve
Open
Open
Three-way
valve
Hi
Lo
Vacuum
pump
adaptor
Vacuum
pump
Vacuum pump
charging hose
Electronic scale
