Valves in figure 45k can be installed on the compressors having high- and low-side access tubes or on the tubing. Remove the valve cap and stem from the valve, clean the joints with acetone as well as sandpaper, braze the correct-size valve on the tube, and allow it to cool before replacing the valve stem and cap.
Numbers 1, 2, and 3 are access valves that are silver-brazed to copper tubing. Number 1 can be used on various diameters of tubing. Number 4 shows the removal of the valve core from the body. Numbers 5, 6, and 7 are T-fittings installed on high- or low-side refrigerant lines. Numbers 5 and 7 are silver-brazed, and number 6 is connected by flared connections. Number 8, shown with its cap, has an extended tube. It can be installed on the compressor access tube as numbers 1, 2, and 3, or on larger sized tubing where in-line fittings may not be available. Drill a hole in the wall of the tubing, insert the valve tube in the hole, and silver-braze the joint. Take great care to prevent foreign particles from entering the system.
INDICATIONS OF A LOW-CAPACITY COMPRESSOR
1. A heavy accumulation of soft frost on the evaporator coil that can be easily removed.
2. Low-side pressure reads higher than normal.
3. High-side pressure reads lower than normal.
4. Low amperage reading when unit is running as compared with the FLA on the unit nameplate. Get an amperage reading from the wire connected to either the run or common terminal. (See fig. 124.)
5. The unit runs constantly.
6. When a residential unit is running, frost covering the accumulator disappears very quickly when the accumulator is held in the hand.