Sanyo CMH3172 Service Manual - Page 59

(5) Recharging Be sure to charge the specified amount of refrigerant in liquid state using the service port of the wide tube service valve. The proper amount is listed on the unit's nameplate. When the entire amount cannot be charged all at once, charge gradually while operating the unit in Cooling Operation. CAUTION Never charge a large amount of liquid refrigerant at once to the unit. This may cause damage to the compressor. When charging with a refrigerant cylinder, use an electronic scale for charging refrigerant. In this case, if the volume of refrigerant in the cylinder becomes less than 20% of the fully-charged amount, the composition of the refrigerant starts to change. Thus, do not use the refrigerant if the amount in the charging cylinder is less than 20%. Also, charge the minimum necessary amount to the charging cylinder before using it to charge the air conditioning unit. Example: In case of charging refrigerant to a unit requiring 1.68 lb. (0.76 Kg) using a capacity of a 22 lb. (10 Kg) cylinder, the minimum necessary amount for the cylinder is: 1.68 + 22 0.20 = 6.08 lb. (0.76 + 10 0.20 = 2.76 Kg) For the remaining refrigerant, refer to the instructions of the refrigerant manufacturer. If using a charging cylinder, transfer the specified amount of liquid refrigerant from the refrigerant cylinder to the charging cylinder. Prepare an evacuated charging cylinder beforehand. CAUTION To prevent the composition of R410A from changing, never bleed the refrigerant gas into the atmosphere while transferring the refrigerant. (Fig. 3) Do not use the refrigerant if the amount in the charging cylinder is less than 20%. 59 Configuration and characteristics of cylinders Valve Liquid Single valve Charge liquid refrigerant with cylinder in up-side-down position. Fig. 1 Valve Liquid Single valve (with siphon tube) Charge with cylinder in normal position. Fig. 2 Charging cylinder NO! Open Liquid Refrigerant cylinder Fig. 3