Submersible pump

[jrdonut]

I currently have a submersible pump 150' down. 1/2 hp franklin put in in 1991. It has served me well. I have a 10 year old open loop geo heating system that requires 4.5gpm. When I installed the system I set my pressure switch to 37-57 with a 80 gallon pressure tank so the pump would not cycle as often. The pump had no problem building up to the cut off point with the geo running until recently. Now it will only build to 50psi with the geo running. Once the geo is off it still builds up to the 57 psi cut off. I figured and I may be wrong but is my pump finally wearing out? Also when the pump kicks in within the last year there is like a hard start noise through the pipes. My local well man sells GRUNDFOS pumps. He gave me a quote on the SQ and The SQE with the controller. All the reviews of the controller are negative. The SQ series are a higher speed permenant magnet motor. I have no idea if this is better or not. I know GRUNDFOS makes the standard pump version yet. I just want something that will last but of course be as efficient as possible. Also he wants to sell me a 3/4 hp in the SQ series. Looking for some professional advice

 

[Valveman]

If the 1/2HP is really worn you don’t need a 3/4HP. But if the old pump is fine and the water level has dropped, which I doubt, then the 3/4 would be a good idea. The 3/4 will increase your electric bill by 33%.

As long as the pump will run continuously when the Geo is on, I would keep using it and just let it do that. You just want to make sure it can build enough to shut off when the Geo or any other water is shut off.

Grundfos makes really good pumps, just not the SQ or SQE. Their regular 4” pumps like the 10S05 or the 7S05 that you need are great pumps. That is what I have on my house and Geo system.

With any of those new pumps the CSV will keep it running continuously while the Geo or any water is being used. Kind of the same way the "VFD controller and the permanent magnet motor" would do, but without all the electrical controllers with there added problems and expense.

 

[Sponsor]

 

[jrdonut]

If the 1/2HP is really worn you don’t need a 3/4HP. But if the old pump is fine and the water level has dropped, which I doubt, then the 3/4 would be a good idea. The 3/4 will increase your electric bill by 33%.

As long as the pump will run continuously when the Geo is on, I would keep using it and just let it do that. You just want to make sure it can build enough to shut off when the Geo or any other water is shut off.

Grundfos makes really good pumps, just not the SQ or SQE. Their regular 4” pumps like the 10S05 or the 7S05 that you need are great pumps. That is what I have on my house and Geo system.

With any of those new pumps the CSV will keep it running continuously while the Geo or any water is being used. Kind of the same way the "VFD controller and the permanent magnet motor" would do, but without all the electrical controllers with there added problems and expense.

Thanks valve man. You must be the same guy I contacted through CSV website. What would be the pipe rattle[1 second] that I hear when the pump kicks in? Never did this before. Can the sound of the motor travel through the pipes or is this just water travel. I was just diagnosing this with the lack of pressure when the geo is on vs a year ago. I could be way off base though. Would you just run my current set up till failure? The pump definitely builds up enough pressure to the cut off point when all water is shut off.

 

[Valveman]

Thanks valve man. You must be the same guy I contacted through CSV website. What would be the pipe rattle[1 second] that I hear when the pump kicks in? Never did this before. Can the sound of the motor travel through the pipes or is this just water travel. I was just diagnosing this with the lack of pressure when the geo is on vs a year ago. I could be way off base though. Would you just run my current set up till failure? The pump definitely builds up enough pressure to the cut off point when all water is shut off.

Yes that was me. And yes I would continue to use that pump until it quits. You may get several more years or several more days, only time will tell.

And if you will remove that check valve above ground your water hammer on pump start will go away.

 

[jrdonut]

Yes that was me. And yes I would continue to use that pump until it quits. You may get several more years or several more days, only time will tell.

And if you will remove that check valve above ground your water hammer on pump start will go away.

Thanks again You have been very helpfull!! One more question then I should be done. Where would this check valve be located and what would int entail to get rid of it. Thanks

 

[Valveman]

It will probably look like a thick brass coupling somewhere before the pressure tank. You can remove it or remove the guts and put it back as a piece of pipe. If you don't have one you can find, I'll bet there is more than 1 in the well, which will still cause the water hammer problem.

 

[jrdonut]

Thanks I thought I was done asking questions but---- I have no check valve above ground. You suggested a couple of standard models of GRUNDFOS 10so5 and 7so5 I went on there website and those pumps have a - number on the end of them. I started looking at pump curves and it was just to much for me to handle. little history on well. 150' deep ,78' static 1 hour of pumping at 6 gpm. Well was drilled in 1981 but never had a pump put in untill 1991 when I bought the property. Pump man installed a Franklin,1/2 230v with a control box. I do not know the gpm of pump that was installed. I do know before the GEO was installed I let the pump run for 24 hours and did a bucket test and I was getting 9 GPM. My geo requires 4.5 gpm plus all the other items in the house. I might just install a new pump this summer or at least have one on hand. I am pretty handy mechanically I just fall short in the electrical area. What exact model GRUNDFOS would you recommend? And where would be a good place to buy? Thanks

 

[Reach4]

You suggested a couple of standard models of GRUNDFOS 10so5 and 7so5 I went on there website and those pumps have a - number on the end of them.

That dash number (as in 7S05-11) is the number of stages. It is not a variant of the pump, and is really just a consequence of the that it takes 11 stages to make a 7 GPM 1/2 HP pump.

I started looking at pump curves and it was just to much for me to handle. little history on well. 150' deep ,78' static 1 hour of pumping at 6 gpm.

The tables are easier for most of us to handle. Note that if you have a slope from the pump, you would adjust the DEPTH TO PUMPING WATER LEVEL (LIFT) IN FEET to take that into account. If there is not much slope, you would use the 80 columns.

 

[jrdonut]

I have very minimum slope. Looks like as you say the 7s05 or the 10so5 would do it. The 10s05 would definitely fill all needs as long as I dont over pump the well. Just two of us living here now.

 

[Reach4]

It seems to me that it would be nice if there would be a valve that could slow the geothermal flow if the house water pressure drops below maybe 35 PSI.

What happens to the used geothermal water?

 

[jrdonut]

you cant slow the flow down on a geothermal. You have certain temp of water going in and a certain temp going out. All done with valves. If you slow the flow down you will freeze the Geo up

 

[Dennis Corvin Blackburn]

If the 1/2HP is really worn you don’t need a 3/4HP. But if the old pump is fine and the water level has dropped, which I doubt, then the 3/4 would be a good idea. The 3/4 will increase your electric bill by 33%.

As long as the pump will run continuously when the Geo is on, I would keep using it and just let it do that. You just want to make sure it can build enough to shut off when the Geo or any other water is shut off.

Grundfos makes really good pumps, just not the SQ or SQE. Their regular 4” pumps like the 10S05 or the 7S05 that you need are great pumps. That is what I have on my house and Geo system.

With any of those new pumps the CSV will keep it running continuously while the Geo or any water is being used. Kind of the same way the "VFD controller and the permanent magnet motor" would do, but without all the electrical controllers with there added problems and expense.

why is the Grundfos SQ not a good pump? I have one on order for a cistern project

 

[Cacher_Chick]

why is the Grundfos SQ not a good pump? I have one on order for a cistern project

The SQ line uses an electronic controller that is expensive and has a tendency to fail for no apparent reason.

 

[Texas Wellman]

The SQ line uses an electronic controller that is expensive and has a tendency to fail for no apparent reason.

No, that's the SQE. The SQ is a good pump, it just spins really fast, making it susceptible to premature wear if there's grit in the water.

 

[Cacher_Chick]

No, that's the SQE. The SQ is a good pump, it just spins really fast, making it susceptible to premature wear if there's grit in the water.

Oops, thanks for that clarification!

 

[Craigpump]

I think the SQE is just as good if not better than other VFD's on the market.

 

[Valveman]

No, that's the SQE. The SQ is a good pump, it just spins really fast, making it susceptible to premature wear if there's grit in the water.

The SQ still has electronics in the motor. However, the electronics in the motor don't seem to have has high a rate of failure as the electronics in the CU301 control box that makes the SQ into an SQE variable speed type pump.

 

[Valveman]

I think the SQE is just as good if not better than other VFD's on the market.

I agree. Grundfos has stuck with this design since about 1999. It has been updated or redesigned about 6-8 times over the years, which has helped to eliminate some of the bugs that are more prevalent in other brands of VFD systems.