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the motor windings to sense the winding temperature and/or current draw. The overload is
connected in series with the common motor terminal.
Should the internal temperature and/or current draw become excessive; the contacts in the overload
will open, turning off the compressor? The overload will automatically reset, but may require several
hours before the heat is dissipated.
9.1.7 Checking the internal overload
1. No power to unit, remove the leads from the compressor terminals.
2. Using an ohmmeter, test continuity between terminals C-S and C-R. If not continuous, the
compressor overload is open and the compressor must be replaced.
9.2 Sealed refrigeration system repairs
9.2.1 Equipment require
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 Welder
7. Electronic Halogen Leak Detector (G.E. Type H-6 or equivalent.)
8. Accurate refrigerant charge measuring device such as:
a. Balance Scales - 1/2 oz. accuracy
b. Charging Board - 1/2 oz. accuracy
9. High Pressure Gauge - (0 - 400 lbs.)
10. Low Pressure Gauge - (30 - 150 lbs.)
11. Vacuum Gauge - (0 - 1000 microns)
9.2.2 Equipment must be capable of:
1. Recovery CFC's as low as 5%.
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 actually introduced into the system.
5. Facilities for flowing nitrogen through refrigeration tubing during all brazing processes.
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