Grundfos 16S07-8 the right replacement pump?

[Reach4]

A Lakos Sub-k might be good for the new pump. https://www.lakos.com/homeowners/

A flow inducer sleeve that extends foot or two below the pump can give much of the benefits for a lot less money.

 

[justler]

A Lakos Sub-k might be good for the new pump. https://www.lakos.com/homeowners/

A flow inducer sleeve that extends foot or two below the pump can give much of the benefits for a lot less money.

Funny enough I just found the Lakos Sub-K and wasn't sure if it was snake oil type stuff or something that would actually work. This is something I would have had done prior to the last well pump being put in because I knew we had some sediment... It hasn't been this bad up to this point.

 

[Sponsor]

 

[Reach4]

https://terrylove.com/forums/index.php?threads/major-sediment-issues.54922/ does not name "subk" but they talk about it.

https://terrylove.com/forums/index.php?threads/sandy-well.75929/

 

[justler]

https://terrylove.com/forums/index.php?threads/major-sediment-issues.54922/ does not name "subk" but they talk about it.

https://terrylove.com/forums/index.php?threads/sandy-well.75929/

It would seem to me at this point i'm going to need a new pump either way.

You had mentioned the 10S07-12. would a 7S07-15 be a better fit or work as well? This is what a local well driller I called recommended based on the GPM refresh of the well I gave from the drilling sheet I posted.

They also have in stock a Sta-Rite 7gpm 3/4 horsepower pump as well that I could get right away.

I could take a colar and make one of those flow inducer sleeves with the wastewater pipe you mentioned to make my own sort of Lakos Sub-K. Worst case I could pull the existing pump and install that myself and maybe pull the pump up 5-10ft? Then I could see how we progress with that and the sediment.

Or at this point is it a better idea to try and get this well pump company out to inspect the well and see where the sediment comes from in the well?

 

[Reach4]

You had mentioned the 10S07-12. would a 7S07-15 be a better fit or work as well? This is what a local well driller I called recommended based on the GPM refresh of the well I gave from the drilling sheet I posted.

Not bad, but not the quite best match IMO. The 7 gpm 1/2 hp is almost enough, but not for a 60 psi cutoff if the water were to fall to 180 ft. The fact that the flow slows as you approach the pump level is not all that bad. That StaRite would be similar. If you were pretty sure that the water would stay above 160, that The 7 gpm 1/2 hp would be a great choice.

Best flow inducer pipe would be solvent weld D2729 sewer pipe.
solvent weld D2729 sewer pipe: OD 4.215 ID 4.056
Schedule 40: OD 4.500 ID 4.026

The D2729 is more flexible. Extend that 2 ft below the pump motor, since you have plenty of room. That shields from sand from above. It is also possible that sand gets eroded by having sandstone around the pump intake. Unlikely. But the shroud/flow inducer would cure that too.


https://terrylove.com/forums/index.php?threads/lets-talk-inducer-sleeves.78342/

 

[justler]

Not bad, but not the quite best match IMO. The 7 gpm 1/2 hp is almost enough, but not for a 60 psi cutoff if the water were to fall to 180 ft. The fact that the flow slows as you approach the pump level is not all that bad. That StaRite would be similar.

View attachment 61394

I was talking about the 7S07-15 which is 3/4. Looks like gpm at 180ft is 6.2gpm or am I reading it wrong?

 

[Reach4]

I was talking about the 7S07-15 which is 3/4. Looks like gpm at 180ft is 6.2gpm or am I reading it wrong?

My concern was more when the water was 36 ft down. You would not be much outside the sweet gray area of the pump, so upthrust would probably be nothing to worry about. Upthrust is the thing you are trying to avoid with too powerful of a pump.

So yes, 7gpm 3/4 hp is good. No qualms.

 

[justler]

My concern was more when the water was 36 ft down. You would not be much outside the sweet gray area of the pump, so upthrust would probably be nothing to worry about. Upthrust is the thing you are trying to avoid with too powerful of a pump.

So yes, 7gpm 3/4 hp is good. No qualms.

The only reason I ask is because if I buy the pump size the drilling/well company recommends and have a problem they will warranty it. Looks like I can get the sewer pipe locally from Home Depot. I just need a 4” to 3” reducer and some stainless worm gear clamps to screw it down and that’s it right? Then just make sure the reducer is 4” above the inlet screen/intake of the pump?

 

[Reach4]

The only reason I ask is because if I buy the pump size the drilling/well company recommends and have a problem they will warranty it.

That is a big thing. Yes, go with that. No worries.

Looks like I can get the sewer pipe locally from Home Depot. I just need a 4” to 3” reducer and some stainless worm gear clamps to screw it down and that’s it right?

Reducer? No. The pump is about 3.75 to 3.9 od. You will cut narrow wedges from the top of the sewer pipe to make it easy for the worm gear clamps to tighten the pipe around the pump part ("wet end") of the pump. You can use Scotch 66 tape from HD, tho the pros use a wider tape sold for well work. Were you thinking of adding a 3 inch diameter tail? No need for that. Just let that tail part be 4 inch. The large diameter of the pipe will make the 9 gpm water velocity low. Sand will not get sucked upward.

The Sub-K adds a centrifugal aspect to the process. Your sleeve will not do that, so it would not be as effective against the finest sand.

 

[justler]

That is a big thing. Yes, go with that. No worries.

Reducer? No. The pump is about 3.75 to 3.9 od. You will cut narrow wedges from the top of the sewer pipe to make it easy for the worm gear clamps to tighten the pipe around the pump part ("wet end") of the pump. You can use Scotch 66 tape from HD, tho the pros use a wider tape sold for well work. Were you thinking of adding a 3 inch diameter tail? No need for that. Just let that tail part be 4 inch. The large diameter of the pipe will make the 9 gpm water velocity low. Sand will not get sucked upward.

The Sub-K adds a centrifugal aspect to the process. Your sleeve will not do that, so it would not be as effective against the finest sand.

I thought I could use a rubber coupler to connect the sleeve to the pump but that looks not necessary according to what you describe, so just a 4" piece of the sewer pipe and a stainless clamp. Slits in it like you said and clamp the slits down so they hold to the pump.

Similar to this video: Around the 2 min mark. Do I need the set screws to center the pump? It's a 4" pump so there won't really be much room inside the pipe..

https://www.rcworst.com/blog/Flow-Sleeves-for-Submersible-Well-Pumps

 

[Reach4]

I thought I could use a rubber coupler to connect the sleeve to the pump but that looks not necessary according to what you describe, so just a 4" piece of the sewer pipe and a stainless clamp. Slits in it like you said and clamp the slits down so they hold to the pump.

Another construction technique would be to put a plastic well seal above the pump on a schedule 40 pipe, and expand the well seal to hold that. It would look fancier, but I don't think that improves the function.

The hold off-screws are not necessary, but you could do that. Valveman doesn't.

 

[Valveman]

Flow inducer or shroud picture.