Pump Automation 1

EEENGRX said:

Yes , I was able to solve the priming issue and it’s now working fine.. self priming

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Great but you still haven't told us how you solved it. We've put time and either into this post and would like to know how it finally got solved. Please.

I,e, what you have done differently or what have you changed?

That foot valve is a necessity in this case, but in the long run, it will turn out to be the weak link in this priming setup. If it is stuck / jammed in some intermediate position, the suction line will not prime. Foot valves fail to work as intended due to corrosion and or bio fouling.

Some common pumps use a flooded case and a venturi.
The impeller drives case fluid through the impeller back into the case.
As the impeller draws in fluid, the pressure builds in the case and fluid is forced out the discharge,
These pumps will handle much more entrained air than a straight centrifugal pump, but too much air will eventually cause loss of prime.
The air separates in the case and the discharge is at the top of the case so that the air is purged.
Not speculation.
I lived with a situation where I used one of these pumps as a booster for a very poor domestic supply.
At times the mains would run dry and the pump would lose prime.
I had a 5 gallon bucket, a flexible line and a petcock to re-prime the pump several times a week.
Was it kludgy?
Yes, but it was cheaper than the alternative.
This type of pump is very common on combination pump and pressure tank units used for domestic wells.
They will often pick-up and fill an empty suction line but not always.
For use with a well, a foot valve is used to keep the suction line full.
Been there done that and have set up many of these pumps.