When pump is installed as shown in
Figure 22: Suction supply above pump on page 27
itself. Open gate valve on suction and close discharge gate valve. Open air vent valves until all air is ex-
pelled and water flows through openings. Close air vent valves, start pump and open discharge gate
valve. Pump will continue to be primed for any future starting.
This method is the simplest and, particularly for automatic operation, the safest. A float switch in the suc-
tion reservoir can be arranged to stop pump, should there be failure of liquid supply.
Priming with foot valve
With pump installed on suction lift, with foot valve at end of suction line, priming can be done any of the
three following ways:
1.
Outside supply
Close discharge gate valve, open air vent valves and open valve in priming supply line until all air
is expelled and water issues from vent openings. Close air vent valves, close valve in priming
supply line, and start pump; then open discharge gate valve.
Figure 23: Priming with foot valve
2.
By separate hand, or manually controlled, priming pump
Close discharge gate valve (keep air vent valves closed) and open valve in line to priming pump.
Exhaust air from pump and suction piping until water flows from priming pump. With priming
pump running, close valve in priming line, start pump and open discharge gate valve.
An alternate method is to reverse connections on priming pump and extending priming pump
suction to source of liquid supply. The pump may be primed by pumping liquid into casing until
liquid comes out of the open air vent valves.
4.3 Priming
28
Model 3415 Installation, Operation, and Maintenance Manual
