Table 4-2. Air Compressor Troubleshooting - continued
CHECK & CORRECTION (Refer to figure 4-1)
3.2.d. Low oil injection pressure indicating switch No. 7 - continued
Check differential pressure drop indicator on filter No. 11 and if high check the filter and replace the cartridge.
Check operation of thermostatic bypass valve No. 14.
If all the checks in the above paragraphs a, b, c, and d, do not reveal the source of the shutdown, check the
switches, relays and connections of the control system and the panel. In case of temperature switches inspect
the capillary line to the sensors and sensors themselves for possible damage.
4. Excessive Oil Consumption
Too much oil in the system (above operating level).
Broken or leaking discharge line or oil injection line.
Plugged oil scavenger line.
Closed scavenge line needle valve No. 18a.
Malfunctioning solenoid valve No. 18.
Loss of power to solenoid valve No. 18.
Scavenge line not reaching bottom of separator element No. 23.
Defective separator element No. 23.
Malfunction of minimum pressure valve No. 24.
5. Air Oil Discharge Temperature Too Low
High oil injection rate.
Fan speed too high.
Fan pitch too high.
6. If all the checks described in the preceeding paragraphs fail to pinpoint the source of malfunction it is recommended
to contact the manufacturer for assistance.
4-3 MAINTENANCE OF AIR CONTROL SYSTEM
4-3.1 Control air Valve. (Figure 4-2)
4-3.1.1 Removal. The operating portion of the valve can be removed without disturbing the air connections. Remove
capscrews (1) to remove the valve from pipe bracket (2). Remove the strainers (3) and gaskets (4) from pipe bracket.
Remove cap nut (13) from housing (12). Remove nuts (9) and lockwashers (10). Separate housing (12) from
Remove nut (5). Remove shaft (7) and ball (8) from yoke (6), then remove yoke (6).