5.3.4 Adding the refrigerant after running the system for many years
Electronic scale
Procedure:
1). Connect the charge hose to the 3-way service port, open the 2-way valve and the
3-way valve.
Connect the charge hose to the valve at the bottom of the cylinder. If the refrigerant is
R410A, make the cylinder bottom up to ensure liquid charge.
2). Purge the air from the charge hose
Open the valve at the bottom of the cylinder and press the check valve on the charge set
to purge the air (be careful of the liquid refrigerant).
3) Put the charging cylinder onto the electronic scale and record the weight.
4) Operate the air conditioner at the cooling mode.
5) Open the valves (Low side) on the charge set and charge the system with liquid
refrigerant.
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