Sorry for the length of this, but the forum sticky does ask for as much info as possible.

I need to replace my submersible well pump and am looking for feedback. I've done lots of reading about well systems and am far more knowledgeable now than I was just two weeks ago, but I still have a lot to learn. That's why I'm here now; I've read lots of good info in this forum and I value the feedback I could receive.

Here are my specifics:

Well is 6-inch casing. Pump is hung at 260 feet on 1" poly. Static level in the well is 16 feet. Rise to the pressure tank is 7 feet, and the highest faucet is 10 feet above that. The total length of poly from pump to tank is 325 feet and includes three elbows and a 1" check valve. So I calculate about 42 feet of head to the faucet not including system pressure. Depth of well is unknown as is recovery rate and pumping level. My neighbor thinks he remembers recovery being 7-8 GPM when it was drilled in 1977/78. I have run two sprinkler heads at a total of 4 GPM for at least ten hours before without running out of water so it's at least that amount. Aside from a failing pump, we've never had water issues in ten years.

Existing pump is a seven year old Goulds 5GS05422 which is a GS Stainless Steel Series, 4", 2 Wire, 5GPM, 1/2HP, 230V. It's thermally cutting out when there's a large volume demand and is drawing about 19A when it starts, so it's on its last legs. I can't get an idea of pumping level in the well because the pump cuts out.

Pressure tank is Well-X-Trol WX-202 20 gallon tank. At 30/50 switch setting, I measure about 5.4 gallons of drawdown. Today the tank is filling from pump cut-on in 45 seconds, so pumping rate is about 7.2 GPM. When I have a healthy pump, I'll be increasing the system pressure to 40/60.

So, the first thing I'm a little puzzled about is why my pump is hung so low in a well that seems to produce fairly decently and has such a high static level. Are those things contributing to the demise of my 1/2 HP 5 GPM pump by causing it to run off to the right of its curve? I know the average life of a pump is just about seven years, but the pump that this one replaced had a date of 1978 on it (not conclusive, but I assumed it was the original pump).

Since I have to replace the pump, this would be a good time to upgrade the system a little. My only complaint when the system was working is that I noticed reduced distance from the sprinklers when I ran both of them. I wish I could recall if this was only when they had been running a while but I wasn't paying close enough attention then. My reading suggests that's not a pressure issue but a flow issue? If I had the ability to run three sprinklers at once, I would. And of course, it would be nice to be prepared for an in-ground sprinkler system in the future.

Looking at pump curves for my existing pump versus higher HP 5GPM pumps or higher GPM rate pumps gives me the idea that the pump type I have is the right one for the well. I think I can go up to a 3/4 HP 5 GPM pump and get higher flow rates at lower pumping levels, but am I risking pumping the well dry?

I'd also like to install a constant pressure / cycle stop valve to help reduce the cycling during sprinkler use. What I don't understand is how that affects the system with respect to reading the pump curve and choosing a pump knowing the valve will be in the system.

Thanks for any feedback or advice you can give.

-Dan Hall
Raymond, NH