R-410A Sealed System Repair - Friedrich Kuhl KCM21A30A Service Manual

R-410A SEALED SYSTEM REPAIR

Refrigeration system under high pressure
O
service this equipment.
R410A systems operate at higher pressures than
R22 equipment. Appropriate safe service and
handling practices must be used.
Only use gauge sets designed for use with R410A.
Do not use standard R22 gauge sets.
5. Manifold sets must be equipped with gauges capable of reading 750 psig (high side) and 200 psig (low side), with a 500-psig
low-side retard.
6. Gauge hoses must have a minimum 750-psig service pressure rating
7. Recovery cylinders must have a minimum service pressure rating of 400 psig, (DOT 4BA400 and DOT BW400 approved
cylinders).
8. POE (Polyol-Ester) lubricants must be used with R-410A equipment.
9. To prevent moisture absorption and lubricant contamination, do not leave the refrigeration system open to the atmosphere.
10. Weigh-in the refrigerant charge into the high side of the system.
11. Introduce liquid refrigerant charge into the high side of the system.
12. For low side pressure charging of R-410A, use a charging adaptor.
13. Use Friedrich approved R-410A filter dryers only.
NOTE:
SEALED SYSTEM REPAIRS TO COOL-ONLY MODELS REQUIRE THE INSTALLATION OF A LIQUID LINE DRIER.
NOTE: SEALED SYSTEM REPAIRS TO HEAT PUMP MODELSMODELS REQUIRE THE INSTALLATION OF A DRIER ON THE
SUCTION SIDE.
EQUIPMENT REQUIRED:
1. Voltmeter
2. Ammeter
3. Ohmmeter
4. E.P.A. Approved Refrigerant Recovery System
5. Vacuum Pump (capable of 200 microns or less vacuum.)
6. Acetylene torch.
7. Electronic Halogen Leak Detector capable of detecting HFC (Hydrofluorocarbon) refrigerants.
8. Digital refrigerant scale
9. High Pressure Gauge - (0 to 750 lbs.)
10. Low Pressure Gauge - (-30 to 200 lbs.)
11. Vacuum Gauge capable of reading 300 microns accurately.
12. Facilities for flowing nitrogen through refrigeration tubing during all brazing processes.
EQUIPMENT MUST BE CAPABLE OF:
1. Recovering refrigerant to EPA required levels.
2. Evacuation from both the high side and low side of the system simultaneously.
3. Introducing refrigerant charge into high side of the system.
4. Accurately weighing the refrigerant charge introduced into the system.
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WARNING
The following is a list of important considerations
when working with R-410A equipment
1.
R-410A pressure is approximately 60% higher than R-22
pressure.
2. R-410A cylinders must not be allowed to exceed 125 F, they
may leak or rupture.
3. R-410A must never be pressurized with a mixture of air, it
may become
flammable.
4. Servicing equipment and components must be specifically
designed for use with R-410A and dedicated to prevent
contamination.