Thread: Max pressure .....

I just had a system installed at my new house. We're drawing water from the lake. The rise from lake level to pump level is 12 feet. The line from the pump to the lake is a 1" line that is 235 ft long. The pump is a Berkeley 3/4 HP jet pump. I have a sediment filter, charcoal filter, and UV light installed, in that order, between the pump and the 44 Gal tank. The tank is pre-charged to 28 PSI, and the working water pressure is 30-53 PSI.

We had tried to set the pressure in the 40-60 range (with a pre-charge at 38), but the pump didn't seem to be able to get to 60. It topped out at 58 PSI and the pump continued to run trying to get it to 60. I tried turning the "shutoff" nut counter clockwise to lower the shutoff pressure to 55, but even with the nut loosened so that it wasn't applying pressure on the spring, I couldn't get the top-end
pressure to lower (ie: stop the pump).

Is 20 PSI the smallest diffential I should expect?

Is 58 PSI the highest pressure I should expect with this setup? Someone had mentioned getting a multi-stage pump (I'm assuming mine is a single stage) to have a higher top-end pressure.

Thanks.

Your Berkley just can't make more than the 58 lbs. That is pretty common with a shallow well jet pump. If you want more pressure, you can change the Venturi tube in the jet to a smaller ID. By doing this though; you will be cutting down on your gallons per minute. Everything is a trade off with a jet pump. You could use a multistage pump with a jet and get another 30 to 60 psi. Jet Pumps
The other answer is to install a submersible pump in the lake. Then pressure and volume won't be a problem.

bob...

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Thanks for the info.

Will my 235ft 1" line become a factor if I were to move to a multi-stage? I'm not sure how I ended up with a 1" intake line. I've only seen 1.25" and 1.5" intake lines before.

I did consider a submersible but was worried about how to deal with a pump problem in the middle of the winter when there's 18" of ice. Not a problem down in Florida, but up north where I live, it would be an issue.

quote:Will my 235ft 1" line become a factor if I were to move to a multi-stage? I'm not sure how I ended up with a 1" intake line. I've only seen 1.25" and 1.5" intake lines before.

1" is definately too small for optimum performance. But since your stuck with it, the multi stage will still make the higher pressure your looking for.

There is also friction loss which is more critical on suction than on pressure.

Another option is the cystern. It's a whole new system added to what you have already, but the pressure would always be there when needed.

quote:I did consider a submersible but was worried about how to deal with a pump problem in the middle of the winter when there's 18" of ice. Not a problem down in Florida, but up north where I live, it would be an issue.

If you were buying your pumps from me, I would say to tee two pumps together in the lake. If one goes out, use the other one.

bob...



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quote:Originally posted by speedbumpIf you were buying your pumps from me, I would say to tee two pumps together in the lake. If one goes out, use the other one.

Or you could duplex them, they would last twice as long for the price of a $10 relay.

Rancher

Rancher,

Do you have duplexing relays in your cache of relays? One never knows when he might need one of those.

bob...

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