Well pump question - well pipe.

[maple1]

Would it be a bad idea - or OK - to put a loop like this in the pipe between my pump & bottom of the well (dug well)?:


That isn't drawn quite right - the pump would be 30'+/- higher than the loop.

 

[heat seeker]

Is it a jet pump? I'm not sure most regular pumps will draw up that far - I forget the max footage. And why the loop?

 

[Retired Guy]

A deep well (two pipe) jet system can easily handle that depth.

 

[heat seeker]

Right! My jet pump raised water about 65'. A regular pump can only draw 33.9 feet under ideal conditions, more like 26 feet in the real world.
I now have a submersible pump that's supposedly good for 150'+. At 65', it's loafing! Jet pumps are rather inefficient, but they get the job done.

 

[maple1]

No issue with the pump pumping the rise - it's been in place & pumping for 10 or so years. It's a 3/4hp jet pump, but set up as a shallow well pump (just uses the one pipe). Before that, there was a 1/2hp pump doing it (or maybe 5/8 if there is such a thing).

I will be needing to pull the pipe this summer, I am quite sure the foot valve has started seeping (pump cuts in a couple times a night). The way it was put in, it's going to be tricky to get out, and will require going into the hole a ways on a rope ladder or the like (not fussy about that part). If I can put it back in with that loop there, it will make it a lot easier to service in the future I think - as well as make it easier to put back in. And also take some stress off the pipe where the pipe comes into the well from the side. Wasn't sure if that loop would present priming/pumping issues by creating an airlock or something like that. I might be able to come up with something else if so.

EDIT: The 30' was a guess - but the well is 20' deep, +/-.

 

[sportbikerider78]

I don't understand the application, but when it comes to fluid dynamics and piping, there is only one thing...head. Every transition has an equivalent straight pipe equivalent. For example...
A 90 degree bend might equal 9' in head loss. A 45 degree might be 6'...and so on. Your loop can be treated as a series of transitions to get an estimate head loss.

 

[maple1]

Heres another sketch of the situation:



The main problem is the 6' - I will need to climb in the well to get the union apart & pull the pipe (it's all copper). Not crazy about that.

If I change most of the copper to plastic & use the loop, or do something like this:


to get the union up where I could reach it from the top, that would make this easier in the future. But doing the last one would add 2 more elbows to the head loss.

If I do the plastic & loop thing, I was thinking the head loss wouldn't be as much as the 2 elbows.

Another factor is the well is 20' deep or so - and now has a little house/shelter built over it. So it would also be easier in the future if I could make most of the copper in the well plastic so it could flex out through the door in the little house when removing/installing. As it is now, I will likely have to cut the copper in a couple pieces, as I pull it up, to get it all out.

I am thinking the loop shouldn't cause a pumping impediment/airlock - but not sure. Which is the main thing I was wondering about.

The well is also about 3' in diameter.

 

[sportbikerider78]

I would not be concerned with adding 2 more 90 degree elbows for such a short run. The additional pipe is almost meaningless since it is going down. Unless you are already stretching your pumps legs...i think you'd be fine.

Does that loop not cause the pipe to be close to the surface and thus in danger of freezing?

 

[maple1]

Freezing, yes - also dealt with that once a few years ago.

After that episode, I put a layer of foam board (1-1/2"?) over the top of the well (floor of the 'house') that seemed to help hold the ground heat in the well. Also try to keep some snow banked up around the outside of the enclosure after that. It only happened the one time. I could also likely put some pipe insulation around the pipe while doing whatever I end up doing.

 

[sportbikerider78]

I'd heat tape the pipe and insulate over that. Just for the super cold days. Digging up stuff a second time is the absolute worst.

 

[Retired Guy]

When we had shallow a well jet pump with our well points we used a check valve at the pump - never a foot valve. Might be easier than pulling it all up.

 

[maple1]

When we had shallow a well jet pump with our well points we used a check valve at the pump - never a foot valve. Might be easier than pulling it all up.

That was suggested to me here too, as a possibility.

That would result in having about 150' of pipe below the checkvalve - wouldn't that create a problem in getting the water from the well to the pump every time the pump kicked in, with all that empty pipe below the check? (Assuming it would bleed out of the pipe over some time...). Or would the water stay in the pipe from the finger-over-the-end-of-the-drinking-straw effect?

 

[Retired Guy]

Your well is 150 ft deep? If so, maybe a check valve wouldn't work. I understood that you had a single pipe shallow well.

 

[maple1]

I do. 150' is pipe length. Well is 20' deep, or I guess more like 14-15' from where the pipe comes into it.

 

[Dr.Faustus]

I had a well that looked a lot like your second sketch. Although it was a submersible pump. When it died, i called a plumber to do the job. Now because i love stuff like this i watched everything they did (they prob thought i was a pest) but they had some kind of tool - i dont know what its called. but they stuck it in the well, and this tool disconnected the union and they pulled the pipe up (and pump) to where they could reach it. This took them all of 2 minutes or less.

I do not know what the tool is called.