Replaced three water pumps within one year. Need help. Any suggestion is appreciated.

[qingdoudou]

I moved into my property in September 2019. The house is outside of the city limits and relies on a 400-foot low yield well. A Littlefuse PumpSaver 233P-1.5 is installed to avoid dry-run. In Summer 2020, the well does not work. The well professionals came and replaced everything, including a new submersible well pump, a new motor, and a (2017) control box. It cost me about $3,000. Since then it had run well for about 3 years.

Last May (2023), the pump stopped working. The Littlefuse red light flashed. First, I replaced the Franklin control box (CB30412CR) with a Tuhorse 3HP Control Box TCB30M230R. The red light was off, but the green light flashed. The pump did not work. I had to call the well professionals. They told me that the pump was broken and replaced the pump (Goulds 7GS20) and motor (CentriPro M20412/200C311). Although the pump was under warranty, I had to pay $1,000 for the labor and rig. Five months later, in October 2023, the pump failed. I paid another $1,000 to replace the pump. Yesterday, April 2, 2024 (another five months later), the story happened again – the pump failed. I paid $1,000.

I am very frustrated. I saw that the pumps and motors were brand new from the sealed boxes every time. It seems that the well professionals were prudent during the installation. In fact, I worked with them as a helper every time. I have no idea why the new pumps stopped working after five months.

Can any one help me avoid having the same trouble again? Is the Tuhorse control box the reason? The first pump lasted 3 years, but after using the Tuhorse control box, each pump only lasted five months. Or is there any other reason the pumps failed in months? Thank you very much. Your advice and suggestions are highly appreciated.

 

[Valveman]

Sorry for your problem. The 3HP box has larger overloads than needed for a 2HP motor. But, by the time an overload shuts it off it is too late. Need to figure out what is causing the problem before you can fix it. Doing an autopsy on the old pump is the best way to figure out what happened. If the impellers are melted the Littlefuse thing is not doing its job and the pump is running dry. If the thrust bearing in the motor is bad, the shaft stickup will be less than 1.5". That would indicate a top feeding well situation where a flow inducer or shroud is needed. Understanding the cause of failure is the best way to prevent it from happening again.

 

[Sponsor]

 

[qingdoudou]

Thank you for your comment. I really appreciate it. The well professionals had to return the broken pump and motor to the supplier for a warranty. They cannot disassemble the pump or the motor. I requested them to ask the supplier, but I am afraid that they would do so.

 

[Valveman]

They are supposed to figure out the cause of failure before they warranty a pump or motor. If they thought you had a Cycle Stop Valve on that system they would scrutinize everything and try their best to find something they could blame on the Cycle Stop Valve for the cause of failure. Lol! Although that has never happened and could never happen.

The reality is there is no one working at the pump company or factory that would have any idea how to figure out the cause of failure. As you have noticed, they don't even look at the pump. If it fails within the warranty period, they just replace it and charge you labor to do so. Many pumps these days are crimped or welded together, as that is the cheapest way to do it, and they are not even able to take them apart for inspection or repair. You can at least still take the pump off of the motor with most pumps these days. Just figuring out which end will turn and which will not is helpful. if the pump is locked down it was probably running dry. If the motor is locked down it is most likely a top feeding well situation and needs a flow inducer. You maybe able to get them to at least tell you which end is locked up.

With a low producing well you may want to consider a cistern or storage tank and booster pump. In this way you can install a much smaller and less expensive pump in the well, as it only has to fill the cistern. Filling the cistern will take a lot of cycles off the well pump, if that happens to be the cause of failure for the old pumps.

Some day soon the pump will last just past the warranty period and you will have to pay again. You will have to figure this out for yourself as pump companies actually like what it happening to you. They make a lot more money when you are having troubles like these than if they install a system that doesn't give a problem for 30 years.

 

[qingdoudou]

Thank you, Valveman! My well system has a storage tank and a booster pump installed, exactly as the figure shown. It took several cycles to fill the storage tank. In this case, the Littlefuse PumpSaver works.
You are right that I have to figure it out. Per your suggestion, I called the well professionals who replaced the pump. The lead told me that the pump company said the pump shaft was broken. It is the pump quality control issue, and I cannot do anything to avoid it.

 

[Valveman]

Thank you, Valveman! My well system has a storage tank and a booster pump installed, exactly as the figure shown. It took several cycles to fill the storage tank. In this case, the Littlefuse PumpSaver works.
You are right that I have to figure it out. Per your suggestion, I called the well professionals who replaced the pump. The lead told me that the pump company said the pump shaft was broken. It is the pump quality control issue, and I cannot do anything to avoid it.

Pump shaft broken and three cycles to fill the cistern. Now we have some data to help.

A dry well condition can be hard on the pump shaft. They unload and grab over and over. But if this is a quality control issue the next time it goes out tell them you want a 7S20-36 instead of the 7GS20. The impellers on the Grundfos 7S20 are lighter than the plastic ones on the 7GS20 and will handle the shock better. Switching to a different brand is also a good reason.

Also, might try restricting the output of the pump so it won't pump the well dry while filling the cistern. it would be better for the pump to run longer at 1 GPM than to pump the well dry three times while filling the cistern. The Littlefuse device may not work when you do that as the amps will drop so low it thinks the well is dry. You can replace it with a Cycle Sensor which can be adjusted to work with a restricted pump running at low amps.

Cycle Sensor Pump Monitor – Cycle Stop Valves, Inc

Buy It! Interactive Animation General Information Specifications Wiring Diagram Installation Instructions Installation Video Troubleshooting

cyclestopvalves.com

 

[qingdoudou]

Thank you, Valveman!!! I will let the well professionals know if I need to replace the pump again. Hopefully, I will not need to do so. And I will consider replacing the Littlefuse with the Cycle Sensor.

 

[qingdoudou]

One more clarification: when the storage tank is empty, it takes several cycles to fill. For example, after when the pump was dead, I had to use the stored water in the tank for over a week before the pump was replaced. It took two cycles.
In normal days, the float switch starts the cycle when the level is low. The tank can be filled within one cycle. In most cases, the Pump Saver does not need to work (i.e., the green light is normally solid, rather than flashing.)

 

[GReynolds929]

A CSV will make it one cycle no matter how much it needs filled, as long as the well can keep up and not run dry, which is where the cycle sensor comes in to play.

 

[Valveman]

One more clarification: when the storage tank is empty, it takes several cycles to fill. For example, after when the pump was dead, I had to use the stored water in the tank for over a week before the pump was replaced. It took two cycles.
In normal days, the float switch starts the cycle when the level is low. The tank can be filled within one cycle. In most cases, the Pump Saver does not need to work (i.e., the green light is normally solid, rather than flashing.)

I think the cycles you are talking about are coming from the Littlefuse cutting the pump off when the well is dry, ad restarting the pump after a certain time. That would cause the shock that would break a pump shaft. However, the cycling could also be caused by the overload in the motor tripping, which will reset and start the pump again after a minute or so. The difference is if the Little fuse is cycling the pump, it could be restricted with a valve. If the overload is cycling the pump, it probably needed a flow inducer as it it getting hot.

 

[qingdoudou]

Hello Valveman,
I would like to update my issue -- the pump stopped working ten days ago (8/18/2024), and was replaced AGAIN this Wednesday (8/28/2024)!!! The pump only lasted 4 months this time. The well pump has been replaced four times since May 2023.

The sleeve of the shaft (a piece of plastic) was broken. Here are some photos.

Here is the new pump:

. You can see that the black sleeve (behind the nut) is intact in the new one, while it is broken in the old pump.

The well pipe is 400 feet long (24 pieces of 16 foot PVC pipe). On Wednesday, the professionals installed two check values on the pipe (one for each 8 pipes), and said the check values could solve the problem. Also, they changed the 3HP control box to a 2HP control box, matching the 2HP pump (7GS20) and motor (M20412/200C31).

Do you think those approaches will solve the problem? Thank you very much for your help.

 

[Valveman]

Sorry for your problem again. That rubber thing is just a sand slinger. It doesn't serve much purpose and the pump will work fine without one. It looks more melted than torn to me, which means the motor got hot. I also see black heat marks on the pump. As I said earlier I think you should restrict the flow and try to keep the pump from running dry in the first place. You may not be able to restrict the pump with the Littlefuse/pump saver, as they see a 25% drop in amps and shut the pump down. Just restricting the pump flow with a ball valve may make the amps drop more than 25%. The Cycle Sensor is designed to be adjusted as low as needed to work with a pump that has been restricted. I think the Littlefuse thing is letting it run too long in the dry condition, which is why it is getting hot.

 

[qingdoudou]

Hello Valveman, thank you very much for your information.
Before replacing the LittelFuse with the cycle sensor, I would like to clarify my situation. The LittelFuse Pump Saver only worked after the new pump was installed because the water level was low. It took 3 cycles to fill up the storage tank. The LittelFuse's green light flashed showing dry run and shut off the pump. After the time I set (4 hours), the pump worked again. Now, the green light is solid green.

Since then, the storage tank can be filled in one cycle. It means that after the first three cycles, the LittelFuse does not work. If the LittelFuse is the issue, the pump should be burnt after the first three cycles.

BTW, I just found that the LittelFuse Pump Saver is 233p-1.5,

, i.e., it is for 1.5 hp pump, while my pump is 2 hp. Is it a problem? Thank you very much.

 

[Valveman]

I'm back. Sorry for delay. All I can say is that motor looks like it has been hot. It only takes 1 GPM flowing past that motor to prevent it from getting hot. Either the Littlefuse is not turning the pump off every time it pumps dry, it is taking to long to shut the pump off after every dry run event, or the flow of water is coming in the well from above the pump and not cooling the motor. Also, running against a completely closed valve, clogged or frozen pipe will do that. The Little fuse is sized for 1/3rd to 1.5HP but I don't know how reliable it is or how long it looks at low amps before shutting the pump off.

Also, the 480' is the minimum head required for a 7GS20. It is made to go down to as much as 950' deep. This is way more pump than needed in a 400' deep well. It could be overheating from overload pumping 10-12 GPM if the water level in the well is shallow, which also causes upthrust. A better choice would have been a 1HP, 7GS10 that would pump 6 GPM from 400' and would only need a water level of 280' to keep from upthrusting.

The Cycle Sensor will shut the pump down after 10 seconds of low amps, and is easy to verify it is working.

With the 2HP already in the well, the best you can do is restrict the flow to like 5-6 GPM and switch to a Cycle Sensor. If the water level in the well is high, that pump could build as much as 380 PSI backpressure when restricted to 5-6 GPM.

The next time you have to replace the pump I would go back with a 7GS10 and install a flow inducer.

 

[qingdoudou]

Thank you very much for your help. I really appreciate it.

 

[Reach4]

Especially if your well may be top-feeding, and if the well is 5 inch or more, the pump should have that flow inducer sleeve. Very cheap, if the pump is getting pulled anyway. Routes the water flow next to the motor.

 

[qingdoudou]

My well is 5-inch. But I have no idea if it is top-feeding. I will let the professionals know the choice next time (hopefully, I will not have the next time.) Thank you very much for your information. I really appreciate it.

 

[Fitter30]

After the first pump the other two should of been sent back to the manufacturer for tear down. How far is the house from well head and depth of pump? 10 gauge wire is good for 456' 5% voltage drop. Pump saver low voltage protection is 190 vac non adjustable. 240 vac would be a 50 volt difference 20% 230vac that's 33 vac difference 17%. How was the sensitivity set up? 2 minutes minimum between starts recommended.

https://s3.amazonaws.com/pumpproducts/pdf/548660_3_Goulds+3-Wire+Motor+Application+and+Installation+Data.pdf

 

[qingdoudou]

The installer took away the burned pumps and did not tell me what the reasons were. For the third pump, I called the installer and was told that the shaft was broken. This time (the 4th pump), I did not hear feedback from the installers.
The house is about 40 feet from the well and the deep of the pump is about 400 feet.
I set the sensitivity to over 3 hours (as shown in the photo in the previous post). Thank you.

 

[Fitter30]

The installer took away the burned pumps and did not tell me what the reasons were. For the third pump, I called the installer and was told that the shaft was broken. This time (the 4th pump), I did not hear feedback from the installers.
The house is about 40 feet from the well and the deep of the pump is about 400 feet.
I set the sensitivity to over 3 hours (as shown in the photo in the previous post). Thank you.

That's restart delay not sensitivity. Page 5.

https://d3d5g87ygmpbyw.cloudfront.net/files/II_111P-233P-1_5P_B1-ENCL-1.pdf