Jet pump configuration for lake use at cottage ?

[John]

Hi folks,

I'm going to install a lake water system at my new cottage and part of that is re-using a Duro 1/2 hp pump from a friend. It was set up at his place in a deep well application with the ejector / venturi unit in his well using a two hose connection between the well and the pump inside his cottage.

His handyman disposed of the ejector so I ended up buying a new universal ejector / venturi unit but it doesn't fit on the pump body, as one would do in a shallow well/lake application like mine (15' lift).

The question is whether or not I should use a double pipe to have the ejector in the lake near the foot valve, or can I just hook it up near the pump and have just a single pipe to the lake. Are there any considerations with priming etc?

Your advice is greatly appreciated,

John

[Harry K]

With a 15ft lift you do not need an ejector. Single pipe works fine with a footvalve.

Priming? Keep your suction pipe as near verticle as possible with the pump as near the lake as you can get. The closer to horizontal any section of the suction pipe is, the more priming problems you will have.

Harry K

[EXT]

If the ejector doesn't fit the pump body, connect it to the body with short lengths of pipe, such as 1 foot long pieces. It will work the same as actually connecting it with the pump. Saves all the double piping, which you don't need.

With a 15ft lift you do not need an ejector. Single pipe works fine with a footvalve.

Priming? Keep your suction pipe as near verticle as possible with the pump as near the lake as you can get. The closer to horizontal any section of the suction pipe is, the more priming problems you will have.

[terry]

We used a Duro pump with about a 12 foot deep well for about 10 years. One of its characteristics was that, from that depth, it was self priming. The venturi jet unit was mounted right on the pump and there was a single pipe down the well almost immediately below. But we understood from the instructions that the venturi could have been detached and placed down a deeper well using a two pipe system. With a 15 foot or less lift a single pipe may be fine; although you may have to prime the pump first time?

[topservicepros]

Not really related to your question but some experience with pumping lake water...

My parents live on the lake and installed a water-source heat pump and used lake water for the heat exchanger. The idea is great - exchange heat with year round ~60 deg water rather than 90deg air in the summer and

30deg air in the winter.

The problem was that the pump would get clogged with silt fairly often (even though there was rigging to keep the intake off the bottom of the lake). In fact the pump had to be replaced about every 2 years!

That may have been an extreme case because I guess that pump is running anytime the heat pump is running so maybe we just had more hours on the pump then you will if you're just using it for irrigation or something.

Anyway, something to consider. When the heat pump needed to be replaced he put in a standard (air cooled) high efficiency unit.

-- Richard Thoms Founder - Top Service Pros, Inc. Connecting Homeowners and Local Service Professionals

[John]

.

Thanks all - I'll connect the ejector with short pieces of pipe. A few other people confirmed that with such short lift the pump will have no problem getting strong suction right off the bat.

John