Uneven water pressure

[Easy Livin’ 3000]

We are on a well with a pressure tank.

The little lady commented (complained?) that her showers sometimes have wonderful pressure, other times not nearly as wonderful.

It is not caused by another simultaneous outlet of water (such as a refilling toilet).

What is causing this, and how can it be fixed?

 

[greg13]

I would start at the pressure tank. Check the charge pressure, You may have a diaphragm leaking.

 

[Easy Livin’ 3000]

I would start at the pressure tank. Check the charge pressure, You may have a diaphragm leaking.

Thanks Greg. I changed my parents pressure tank years ago because of a leaking diaphragm. The rubber had considerable rotting. Sounds like the likely cause. Looks like a new blue tank is in our future.

 

[semipro]

The submersible pump pressure switch is typically set with a 20 PSI between cut-in and cut-out pressures. 20 PSI can make a big difference in the quality of a shower, especially on the upper floors of a house.
There should be a gauge at the pump tank that shows pressures. Open the taps and watch the gauge to determine the cut-in and cut-out pressures.
You can then either adjust one nut in the switch to increase the overall pressure (e.g. going from 40-60 to 50-70) or you can adjust the cut-in and cut-out pressures individually. This is a pretty good reference: http://www.sta-rite.com/resources/images/13433.pdf

Edit: in our house, for a variety of reasons, we ended up installing a booster pump that increases the pressures created by our submersible pump.

 

[heat seeker]

I can tell when my whole-house filter needs changing. There is a very noticeable difference in my shower pressure as the pump cycles on. A new filter, and I can't easily tell when the pump kicks on.

 

[Easy Livin’ 3000]

The submersible pump pressure switch is typically set with a 20 PSI between cut-in and cut-out pressures. 20 PSI can make a big difference in the quality of a shower, especially on the upper floors of a house.
There should be a gauge at the pump tank that shows pressures. Open the taps and watch the gauge to determine the cut-in and cut-out pressures.
You can then either adjust one nut in the switch to increase the overall pressure (e.g. going from 40-60 to 50-70) or you can adjust the cut-in and cut-out pressures individually. This is a pretty good reference: http://www.sta-rite.com/resources/images/13433.pdf

Edit: in our house, for a variety of reasons, we ended up installing a booster pump that increases the pressures created by our submersible pump.

Thanks Semipro. Our line in from the well pump goes into the pressure tank. Is this what you mean when you say pump tank? It's light blue.

 

[semipro]

Thanks Semipro. Our line in from the well pump goes into the pressure tank. Is this what you mean when you say pump tank? It's light blue.

Yes.
@heat seeker's point is a good one too. A restriction, such as a clogged filter, will create flow problems even though pressures are good.

So 40 PSI is fairly low. If that's near the low pressure cut-on point that may be ok. You'll want to watch that gauge while someone uses water to see what your on-off pressures are. 40-60 may be okay but you can certainly go higher. 20-40 would be low.

 

[Easy Livin’ 3000]

I can tell when my whole-house filter needs changing. There is a very noticeable difference in my shower pressure as the pump cycles on. A new filter, and I can't easily tell when the pump kicks on.

No filter here. I've been meaning to install one, as the aerators on the faucets catch the solids and the sprinkler heads outside need a couple of flushes each season in the garden. I'll consult here when I eventually get around to this.

It does make me wonder of some of the junctions are partially clogged with corrosion and grit.

 

[Highbeam]

City pressure is constant. Residential well pressure is not. That 20 psi range is very noticeable with modern shower heads and faucet aerators.

 

[Easy Livin’ 3000]

Yes.
@heat seeker's point is a good one too. A restriction, such as a clogged filter, will create flow problems even though pressures are good.

So 40 PSI is fairly low. If that's near the low pressure cut-on point that may be ok. You'll want to watch that gauge while someone uses water to see what your on-off pressures are. 40-60 may be okay but you can certainly go higher. 20-40 would be low.

We'll have a look this afternoon and see.

What's that air valve on the top of the pressure tank? My first instinct is to pump some air into it.

 

[semipro]

https://www.watertechonline.com/troubleshooting-a-bladder-pressure-tank/

 

[greg13]

I just took another look at your picture and the fact that there are iron pipes could be a factor also since they could be corroded inside.I would get rid of them, even if it is only a small section.Also bump up to at least 3/4" pipe or tubing.

 

[maple1]

We'll have a look this afternoon and see.

What's that air valve on the top of the pressure tank? My first instinct is to pump some air into it.

You don't want to just put some air in. The air should be set to a certain amount - typically maybe 1 or 2psi more than your cut-in pressure. And you set it when there is no water pressure on it. Or at least, less than what you are trying to set it to.

With no filter, it could be a number of things. Buildup somehere or anywhere. But I would first suspect at the pressure switch - they usually are connected by a little hose to the system or fitting on the pump. It doesn't take much dirt sometimes to interfere, so that the switch isn't sensing the water pressure correctly.

We are good here with pressures in the 25-40 range.

 

[sportbikerider78]

Thanks Greg. I changed my parents pressure tank years ago because of a leaking diaphragm. The rubber had considerable rotting. Sounds like the likely cause. Looks like a new blue tank is in our future.

Depending on what size you have, you may want to upsize it as well. Bigger tank means less cycling for the pump, and that means extended life.

 

[ToltingColtAcres]

https://cyclestopvalves.com/pages/csv1a

 

[semipro]

https://cyclestopvalves.com/pages/csv1a

Man, are these things controversial.
I bought one fully intending to install it but am now convinced that it may consume more power than the stock pump setup. No doubt it will decrease the number of submersible pump on-off cycles but at what cost?
We run an open-loop ground source heat pump that uses our deep well as heat source/sink so the thought of decreasing pump cycling is very compelling.

 

[ToltingColtAcres]

I installed one about a year ago. I have tankless electric hot water heaters in my bathrooms which supply hot water. They are extremely susceptible to variable water pressure -- and would often turn off when the water pressure dropped to the point where the pump would come on. By installing one of these, I do not experience the variable water pressure any longer, and the shower doesn't suddenly go cold in the middle of me sudzing up. More electricity? Probably.

 

[Easy Livin’ 3000]

Man, are these things controversial.
I bought one fully intending to install it but am now convinced that it may consume more power than the stock pump setup. No doubt it will decrease the number of submersible pump on-off cycles but at what cost?
We run an open-loop ground source heat pump that uses our deep well as heat source/sink so the thought of decreasing pump cycling is very compelling.

I guess the obvious question is- how much more electricity? I watched a couple of videos and it seems compelling. We only have two people living here, and only one of us takes showers every day, so I can't imagine the electric use would skyrocket. We do run quite a bit of water to the garden in the summer.

Just what I need, another project!