Refrigerant Removal, Recovery, And Evacuation - Friedrich Chill Premiere Series Service Manual

Refrigerant Removal, Recovery, and Evacuation

NOTE: When accessing the refrigerant in the system to make repairs or for any other purpose, conventional procedures shall be used.
However, for FLAMMABLE REFRIGERANTS (R-32 is classified in the A2L group for mildly flammable refigerants) it is important that
best practice is followed since flammability is a consideration.
Warning:
Ensure sufficient ventilation at the repair place.
Warning:
Ensure there are no open flame sources or hot surfaces that exceed 1200˚F in the work area.
Warning:
Discharge capacitors in a way that won't cause any spark. The standard procedure to short circuit
the capacitor terminals usually creates sparks.
1. Install a piercing valve to remove refrigerant from the sealed system. (Piercing valve must be removed from the system before
recharging.)
2. Safely remove refrigerant following local and national regulations. (Refer to local governing bodies for refigerant handling.)
Recovery
a. When transferring refrigerant into cylinders, ensure that only appropriate refrigerant recovery cylinders are employed.
Ensure that the correct number of cylinders for holding the total system charge is available. All cylinders to be used are
designated for the recovered refrigerant and labelled for that refrigerant (i.e. special cylinders for the recovery of refrigerant).
Cylinders shall be complete with pressure-relief valve and associated shut-off valves in good working order. Empty recovery
cylinders are evacuated and, if possible, cooled before recovery occurs.
b. Make sure that cylinder is situated on the scales before recovery takes place. The recovery equipment shall be in good
working order with a set of instructions concerning the equipment that is at hand and shall be suitable for the recovery of the
flammable refrigerant. in addition, a set of calibrated weighing scales shall be available and in good working order. Hoses shall
be complete with leak-free disconnect couplings and in good condition.
c. Do not mix refrigerants in recovery units and especially not in cylinders.
d. If compressors or compressor oils are to be removed, ensure that they have been evacuated to an acceptable level to make
certain that FLAMMABLE REFRIGERANT does not remain within the lubricant. The evacuation process shall be carried out prior
to returning the compressor for inspection. Only electric-type heating to the compressor body shall be employed to accelerate
this process. When oil is drained from a system, it shall be carried out safely.
e. Start the recovery machine and operate in accordance with instructions.
f. Do not overfill cylinders (no more than 80 % volume liquid charge).
g. Do not exceed the maximum working pressure of the cylinder, even temporarily.
h. When the cylinders have been filled correctly and the process completed, make sure that the cylinders and the equipment
are removed from site promptly and all isolation valves on the equipment are closed off.
3. Open the circuit by cutting with a refigeration tubing cutter. Always open the low side first.
The refrigerant charge shall be recovered into the correct recovery cylinders.
Transportation
Be aware that local, state, and national codes exist that regulate the transportation of flammable gases. Be sure to become informed of the
regulations and always stay compliant.
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R-32 SEALED SYSTEM REPAIR