Question about Grundfos JPS4 1 HP Pressure Booster Pump

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My pump cuts in and out when the tap is turned on but now does not seem to pump the water up and does not seem to be sucking. what can I do? is there a manual I can down load on how to do it?

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If you have not had the electric shut off to the pump then there is a good possibility that the foot valve has gone bad at the bottom of the well pipe....this allows the water to back nto the well adn then the pump gets air in it...then the pump will not pump may be able to get it to go but it will require filling the pipe(s) with water and then purging the air from the pump...

Here is a tip that I wrote about how to do that...

Jet Well Pump Well Jet Water Pump


Posted on Jan 03, 2011

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Posted on Jan 02, 2017

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I have a submersible water pump It seems to suck ...

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Problem with Convertible Jet Pump 3/4HP RedLion - drawing water 300' from lake to cabin - when the pump is on it holds 50# pressure by itself but when tap is turned on the pressure drops to 30# then you...

If I understand you correctly this is what you have:

- A pump that draws water from a lake 300 feet from lake to your cabin (I assume the pump is at the cabin)

- The pump kicks on to maintain pressure in a tank that distributes water to faucets in the cabin. The pump only turns on to pressurize the tank when water is being used (I am assuming).

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- The pump is not used regularly.

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One other possibility is clogged strainer(s) / filter(s) in the water lines. It would not hurt to pull and check/clean any strainers / filters in the system including before the pump. I would even check at the lake for a strainer where the water enters the suction line to the cabin.

I would not assume that the pump is the problem yet.

Hope this helps.

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