Recharge System (A/C-2). (Cont)

TM 55-1905-223-24-17

(4) With the system evacuated, and gauge manifold still hooked to compressor, connect the

common hoseline of the manifold to a R-22 refrigerant container.

(5) Crack the valve on the R-22 container momentarily and then close. Loosen the common

hoseline connection at the manifold to purge the hose, then re- secure the connection.

WARNING

Do not use water warmer than 110 to avoid over-expansion of refrigerant in

container.

(6) Place the refrigerant container upright in a container of warm water that is no, warmer than

110 . This will maintain container pressure and expedite charging.

WARNING

DO NOT apply heat with a torch.

(7) Start the compressor. Slowly open the low side handwheel on the combination gauge. DO

NOT open the high side handwheel. Charging must be accomplished through the charging

valve on the suction line.

(8) Observe both gauges on the manifold while charging. Also observe the sight glass in the

liquid line.

(9) When operating pressures are within proper range (suction: 58-72 psig; discharge: 170-230

psig), close the combination low side handwheel on the manifold. Check the sight glass. If

bubbles, or a stream of bubbles, are observed, crack the low side handwheel and add more

refrigerant until sight glass clears. DO NOT continue adding after sight glass has cleared.

(10) The actual weight of refrigerant added to the system can be determined by weighing the R-

22 container(s) again and deducting the weight(s) obtained from initial weight(2) recorded

before recharging.

(11) If the result is in excess of the amount required by the unit's dataplate, secure the

compressor and release a small amount of refrigerant. Close the valve on the R-22

container, make sure the handwheel on the combination gauge is closed, and disconnect the

common hoseline from the R-22 container. Release a small amount of refrigerant by

momentarily cracking the handwheel on the combination gauge. Take care not to release

too much, or refrigerant may have to be added back.

(12) Start the compressor, allow to run for 5 minutes, and again check operating pressures and

sight glass.

(13) When charging is complete, stop the compressor and close the suction and discharge

service valves fully counterclockwise. Disconnect the gauge manifold and install protective

caps on both service valve stems and gauge connections.

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