4 Starting pump
4.1 Priming
The pump must always be fully primed and the suction pipe full of liquid before pump is started.
If pump is run dry, the rotating parts within the pump may seize to the stationary parts as they depend on
the liquid being pumped for lubrication.
Several different methods of priming can be used, depending on the type of installation and service in-
volved.
NOTICE:
If the pump is being used to pump potable or drinking water, the priming line should be protect-
ed against back-siphonage by the installation of a check valve and an approved type vacuum
breaker.
Suction Supply Above Pump:
When pump is installed as shown in
, pump will prime itself. Open gate valve on
suction and close discharge gate valve. Open air vent valves until all air is expelled and water flows
through openings. Close air vent valves, start pump, open discharge gate valve, and pump will continue
to be primed for any future starting.
Figure 13:
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
following three ways:
1.
). Close discharge gate valve, open air
vent valves and open valve in primary supply line until all air is expelled and water issues from
vent openings. Close valve in priming supply line, close air vent valves and start pump; then
open discharge gate valve.
4 Starting pump
3405-3406-3416 Installation, Operation and Maintenance Instructions
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