Parallel Compressor Systems
to the compressor.
Before the oil separator is installed, an initial charge of oil must be added to it. This initial charge of oil is the amount that is needed to just float the needle valve float. This amount of oil will stay in the oil separator when in operation and will seal the needle and prevent damage to the float mechanism. Oil Precharge is very important. Failure to Precharge the separator sump may result in damage to the oil return float mechanism by the turbulent hot gas bouncing the float and causing the needle valve to leak.
New systems from the factory have been Precharged. Use the same type of oil that is in the compressor crankcase.
See the table below for the proper amount of oil to be Precharged.
Temprite Valve Adjustment
Turn in (clockwise) to increase pressure. Turn out (counterclockwise) to decrease pressure. Approximately 7 psi per turn. Factory set at 40 psi ±2.
Table 21. Temprite Models
Temprite Model |
|
No. | Oil Precharge |
922R, 923R | 77 oz. / 2.2 L |
|
|
924R , 925R | 109 oz. / 3.22 L |
|
|
926R, 927R | 1.8 gal./ 6.7 L |
928R | 3.5 gal. / 13.25 L |
|
|
930R | 5.7 gal . / 21.25 L |
|
|
Figure 17. Temprite Oil System
Table 20. AC&R Models
Helical | Oil |
Model No. | Precharge |
4 oz. / 11 cl | |
14 oz. / 40 cl | |
|
|
40 oz. / 114 cl | |
|
|
25 oz. / 71 cl |
Conventional | Oil |
Model No. | Precharge |
12 oz. / 34 cl | |
30 oz. / 86 cl | |
|
|
25 oz. / 71 cl | |
|
|
12 oz. / 34 cl |
Temprite Models
The Temprite brand used is the coalescent filter type separator. Because this filter is finer than a filter/drier, it will pick up any and all effluent and dirt circulating in the system down to 0.3 microns. These filters should be changed after 24 to 48 hours of initial run time. A second filter is supplied with the system for this purpose. If the filter becomes dirty, it will not function at its optimum performance level. In the event of a compressor burnout, all the effluent will be contained in the oil separator.
When the Temprite coalescent separator is used, the separate oil reservoir is not required. The oil separator serves the additional function as the reservoir. There is a constant pressure valve used between the oil return outlet and the oil level regulators to maintain a low pressure oil flow to the regulators. This valve should be adjusted to maintain oil pressure to the level regulators at 20 psig higher than the highest suction pressure group. This valve can be adjusted by removing the external cap and rotating the adjusting spring in or out as required.
The valve currently used is manufactured by Parker and is a model A7 constant pressure expansion valve with a range of 0 to 90 psig. Temprite Part No. is 67070000. An alternative valve manufactured by Sporlan is Model ADRI - 11/4 - 0/90.
Oil Level Regulators
The AC&R adjustable oil regulators are designed to feed oil between 1/4 and 5/8 sight glass levels. The regulator may adjust beyond this range due to the actual oil pressure. Adjustable regulators include an adjustment mechanism to raise or lower the oil set point. The AC&R design eliminates the need to shut the system down in order to adjust the oil level. The oil level may be adjusted while the system is under pressure and running. Adjust the oil level by removing the seal cap, the locking disk
All level regulators have a operating pressure differential range that should not be confused with its working pressure. The operating differential is the difference of pressure between the oil feeding into the regulator and the component where the regulator is controlling oil level. Specifically, the reservoir pressure minus the crankcase pressure. If the differential pressure is too low for that regulator, insufficient oil flow to the compressor may result. If the differential pressure is too high, the regulator will overfill.
Parallel Compressor Systems Installation & Operations Manual, October 2004 | 27 |
