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  #1  
Old 05-30-2013, 04:49 PM
A23 A23 is offline
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Pump loses prime overnight?

Ok here's the deal....I've got a well pump on a shallow well (30 ft or so, but the water table is 15ft) that loses prime overnight. The pump checks out ok, nothing wrong with it. There's a check valve right before the intake side, as well as right after the discharge side. It takes about 4-5 minutes to prime itself when you turn it on in the morning, but there's plenty of water and pressure to run the 4 sprinkler zones through a full cycle.

The well driller that installed it about 5 years ago says that he thinks that the water table has dropped too low and all of the water is running back down the drop pipe, but that doesn't make any sense to me because there's 2 check valves and plenty of water / enough of a recharge to run the sprinkler system just fine once the pump is primed.

Any suggestions?

Last edited by A23; 05-30-2013 at 04:56 PM.
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  #2  
Old 05-30-2013, 05:49 PM
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zturncutter zturncutter is offline
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Is the check valve on the intake side brass or plastic ?
Is it mounted horizontal or vertical ?
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  #3  
Old 05-30-2013, 06:56 PM
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Wet_Boots Wet_Boots is offline
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If you pump any sand at all, the checks can fail to seat tightly.
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Old 05-30-2013, 07:12 PM
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greenology greenology is offline
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When you say a check valve right before the intake side, are you talking about it being installed on the pump itself? I could be wrong but I think you need a check valve on the beginning of your intake pipe, which would be submersed in the well. Im not sure whether a check valve on the pump side of intake would be enough to stop the intake pipe draining back down the the water level.. However you say you've had it for 5 yrs like this, so must be ok.

The water table dropping over night wont make any difference to you as the check valve will keep the lines primed. The driller sounds a bit dopey for suggesting that... Sounds like you need to instal a check valve at the well side of your intake pipe.
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Old 05-30-2013, 07:17 PM
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greenology greenology is offline
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Or if this is where the check valve is already, then you just need to replace or repair it. Only other way it can lose its prime is if the pump was running while the water table dropped below the inlet pipe, then the pump will drain the pipe.
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Old 05-30-2013, 08:29 PM
windflower windflower is offline
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It can lose prime if there is a hole in the drop pipe.
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  #7  
Old 05-30-2013, 10:54 PM
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greenology greenology is offline
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Quote:
Originally Posted by windflower View Post
It can lose prime if there is a hole in the drop pipe.
Missed this one
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  #8  
Old 05-31-2013, 05:54 AM
A23 A23 is offline
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Thanks for the input so far..... yes they are PVC check valves, mounted horizontally about 8 inches away from the pump on both the intake and discharge sides. Down here they don't really use foot valves, just a well point with a check valve near the pump. I agree that the well driller is full of BS on this one, cuse I don't see how the drop pipe would drain out without there being a problem in the line somewhere.

Have you all seen more issues with check valves mounted horizontally like that?
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Old 05-31-2013, 07:08 AM
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greenology greenology is offline
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My thoughts would be that you've had no problem for 5 yrs correct? So the way the pump/check valves are set up must be suitable.

Which means that theres likely a problem with a check valve.
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  #10  
Old 06-02-2013, 07:25 AM
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jvanvliet jvanvliet is offline
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check the seals on the pump.

BTW pvc check valves are crap.
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