Short Cycling Well Pump — Stop me if you're heard this one

[JH Steve]

Hi,

I'm having the same problem others have had with short cycling. Based on what I learned here, it seemed like bad a check valve. I pulled the check valve and it was indeed bad — I could blow through it both directions. I put in another check valve, drained the (full) water tank, put in 28 psi, and powered everything back on. I can isolate the house aft of the tank, and it still short cycles every 30 minutes or so. Now, there's a much longer delay before the pump runs after water use/flushing and instead of running for 8 or 10 seconds, it runs longer, like a minute to get back up to pressure. For some reason it also runs quieter. The check valve I used was one that a buddy had in his garage. It was still in the box and I blew in it and could only blow in one direction. So my question is this. Do you think I installed a second bad check valve, or is it more likely something else? If it's something else, can you give me some diagnostic steps? I'm pretty new to well water but have access to most tools and am determined to find a DIY fix.

 

[Reach4]

Submersible pump? Assuming yes. The only check valve should be down at the pump.

Your check valve at/in the pump could be bad, or you could have a hole in your pipe from the pump, or the o-ring at the pitless could be leaking.

 

[Sponsor]

 

[LLigetfa]

I put in another check valve, drained the (full) water tank, put in 28 psi, and powered everything back on.

You also need to replace the tank.
What type of pump and where is the check valve?

 

[JH Steve]

Submersible pump? Assuming yes. The only check valve should be down at the pump.

Your check valve at/in the pump could be bad, or you could have a hole in your pipe from the pump, or the o-ring at the pitless could be leaking.

Submersible pump -- yes. The check valve I replaced is connected to a nipple that connects to the polyurethane well pipe that comes into the house. I'll post a picture in a bit.

 

[JH Steve]

You also need to replace the tank.
What type of pump and where is the check valve?

submersible pump, 100+ feet down, which I've never seen. I suppose it would have a foot valve (???). But there's a check valve between the poly and the tank, which is what definitely failed, and which I replaced.

 

[Reach4]

submersible pump, 100+ feet down, which I've never seen. I suppose it would have a foot valve (???). But there's a check valve between the poly and the tank, which is what definitely failed, and which I replaced.

Foot valve is a terms for a check valve with an intake screen. That would not apply to submersible pump. There needs to be a check valve at the pump. Many pumps have a built-in check valve, and many add a check valve right above the pump. A check valve up top can be used as a workaround for a leak, but normally you don't want one. Often you can take the poppet out of a check valve to disable that action.

 

[JH Steve]

Foot valve is a terms for a check valve with an intake screen. That would not apply to submersible pump. There needs to be a check valve at the pump. Many pumps have a built-in check valve, and many add a check valve right above the pump. A check valve up top can be used as a workaround for a leak, but normally you don't want one. Often you can take the poppet out of a check valve to disable that action.

 

[JH Steve]

Okay, so here's the rig. What I'm hearing is that the check valve coming into the T before the gauge was most likely added as a stop-gap measure because there's a failed check valve on the pump, or because there's a leak somewhere between the pump and the second check valve that's probably hard to find, hard to get to or both. Does that sound right? Next question: If the check valve in the picture is good, wouldn't the problem go away? (And if so, is there anything wrong with just getting a good secondary check valve, or do I really need to find the leak? (Also, thank you! This has been a great education)

 

[Valveman]

If that check valve at the tank was working, you would not be losing pressure when no water is being used. If you put a new check valve at the tank, the pressure leak will stop, but it will cause either air in the water or water hammer on pump start. Air will blow a glass out of your hand at the sink if there is a leak in the line down the well. A big water hammer thump will happen every time the pump starts if the lower check is leaking back. Replacing the check down on the pump and/or fixing the hole in the pipe and removing the check at the tank is the only real fix. But adding a new check valve at the tank and living with the water hammer or air in the lines maybe a temporary fix. You can just move this check valve down to the pump when you get around to pulling the well pump.