Sanyo SPW-CR1503GDYH8 Technical Data & Service Manual page 328

1. Compressors
(1) Vacuum and Oil and Refrigerant Injection
[Measurement of oil amount]
Measure the oil amount in the faulty compressor and the oil amount recovered in the oil separator to determine the
amount of new oil to be added.
Total amount of
recovered oil (l) (two
–
compressors and oil
separator)
[Vacuum]
1. Close the V9 valve, open the V3 and V7 valves, and start vacuum pump operation. (Both oil tank valves are
closed.) (The V1 and V2 valves are open, the V5, V6, and V8 valves are closed, the balance pipe valves 1 are
closed, and 2 is half-way open.)
2. Make a vacuum so that the vacuum low-pressure gauge reaches 133.3 Pa (1 mmHg).
3. Once this is reached, close the V7 valve, and then stop the vacuum pump.
[Oil injection]
Refer to "(2) Air Purging with a Vacuum Pump, refilling the oil/refrigerant" (P VII-11).
[Refrigerant injection]
Inject an amount equal to the amount recovered by the refrigerant recovery device plus 0.5 kg.
1. Open the V1, V2, and V8 valves, and close the oil tank valves and V3 valve. If all of the oil cannot be injected,
operate another outdoor unit, and inject from the low-pressure discharge outlet of the operation unit in gaseous
form. (Use the weighing scale.) If you cannot finish injection using this method, enable operation in all of the
outdoor units, and then operate all of the outdoor units, and perform injection using this gas injection method.
(2) Cleaning of the Dry Cores in the System
One cause of repeated burning and other faults in compressors in the same piping system is acid, sludge, carbon, or
other substances remaining in the refrigeration cycle. This is often due to inadequate cleaning. Perform cleaning prop-
erly by following the procedure below.
¶
When a ball valve is installed at the outdoor unit side
Install the service pipes as shown in Fig. B (P20).
1. Operate all of the outdoor units (either cooling or heating operation is OK).
2. Close the liquid pipe valve and ball valve of the outdoor unit where the dry core is to be mounted.
3. Immediately close the V1 valve, and then once operation is performed for 10 seconds, stop the outdoor unit. (The
pipe contents are pumped down inside the piping.)
4. When the outdoor unit stops, close the V1 valve.
5. Remove the pipe between the liquid pipe valve and ball valve, and then mount the designated dry core. (This varies
according to the specific model. This uses the flare connection method.)
6. Inspect for leaks in the pipe where the dry core is mounted (nitrogen pressure: approx. 1.96 MPa (20 kg/cm
7. Make a vacuum in the pipe where the dry core is mounted (133.3 Pa (1 mmHg)).
8. Open the liquid pipe valve and ball valve.
9. Turn on the outdoor units.
10. Perform the above procedure for each outdoor unit.
11. Run each outdoor unit in this state for about three hours.
12. Follow the procedure above, and replace each dry core with a new one.
13. For the second time in this state, operate each outdoor unit for about 20 minutes.
14. Extract a small amount of oil, and check its smell, color, and overall appearance. If it meets the designated criteria,
remove each dry core to complete the procedure. If the oil does not meet the designated criteria, replace each dry
core with new ones again. Repeat this procedure until the oil meets the designated criteria.
Amount of oil to be added
8.2 l (PC unit)
=
(l) (If the result is negative,
no oil needs to be added.)
VII - 13
Replacement of Main Units
2
)).
TD831077
7