Trying to understand my well's water pressure

[NoFortress]

I purchased a home with a well recently; before this house I've never had well water and have been trying to education myself on how it works. The showers in the house all seem to have poor water pressure and I've been trying to diagnose this. I've showered in homes with well water (my in-laws have well water, for instance) so I know the situation can be improved. The water pressure is also inconsistent; all of the showers seem to have poor pressure, but many of the sinks do not. There's a double vanity in the main bathroom and my sink has much stronger pressure than my wife's. I've cleaned out the aerators on all the sinks and replaced every shower head in the house, but this did not seem to have any impact on pressure.

Background info: the house is ~18 years old and was rented for most of its life. There is a water softener but I suspect the tenants did not consistently refresh the salt. Many of the fixtures have scale buildup on them. We have a pressure tank in our basement with a standard 40/60 pressure switch on it. I took a timelapse of the gauge at the pressure tank here (I turn a shower on shortly after the video starts). What I expected to see was a slow, constant decrease in pressure from 60psi to 40psi, at which point the switch would turn on the well pump and it would increase back to 60psi. Then rinse and repeat. Instead it decreases like I would expect to 50psi, then drops rapidly down to 30psi before the pump kicks on. I took a real-time video here (I fiddled with the screws a bit on the pressure switch between these two). I similarly took timelapses of the pressure at two different shower heads; here is one on the main floor of the house and here is one upstairs (the pressure tank is in the basement). From what I've read I can expect a 4-5psi pressure decrease per floor, but the upstairs shower head is getting down to 11psi before the pressure switch engages. These are the things I do not understand:

1. Why does the pressure at the tank decrease rapidly below 50psi just before the switch engages? Is this expected? I can't tell, given the sudden drop in pressure, if the pressure switch is engaging at 30psi or 50psi.
2. Why am I seeing such low pressure at the shower head?
3. Why is the pressure curve so different at the pressure tank compared to the shower head? The decrease is fairly linear between the high and low points at the shower, but much more erratic at the pressure tank.

 

[Valveman]

The pressure tank is waterlogged. If will probably show 50+ PSI in the air chamber, but that is because water go in the air chamber where it should not be. The diaphragm tears from going up and down every time the pump cycles on and off. Even a slow climb to 60 and a slow drop to 40 can still add up to hundreds of cycles per day. Once the tank is waterlogged, the pump is not long lived, as it is cycling even faster now. Probably been getting worse every day, but still needs to be fixed as soon as possible.

You should never mess with the small adjustment screw in the pressure switch. Since you already have, just loosen it as much as possible, where it isn't even touching the little spring. Adjust the large adjustment screw to shut the pump off at or close to 60, and the on pressure will take care of itself and is not that important.

Instead of just replacing the tank you can fix the cycling problem and get strong constant pressure in the house with one of these.

Custom PK1A PSIDE-KICK Pressure Tank Kit

Replaces large pressure tanks. Preset and easy to install for the DIY customer. The pside-kick kit is a complete constant pressure control package for most pump systems with demands from 1 to 25 gpm. This kit comes with everything you see and utilizes a mechanical pressure switch.

cyclestopvalves.com

With a two story house I would use a 50/70 pressure switch. But even with a 50/70 switch the pressure is always going up to 70 and back down to 50. A CSV would hold a strong constant 60 PSI, which makes a big difference. As your excellent tests have shown, the pressure fluctuates even worse at the shower head, and that was without the shower head being used at the time. With 60 PSI constant at the PK1A you will see 50 PSI constant in the upstairs shower.

 

[Sponsor]

 

[NoFortress]

I do not think the pressure tank is waterlogged, but I’m willing to be convinced otherwise. The pressure at the valve stem measures identically to the gauge I recorded, which I’d expect. I recently drained the pressure tank and it measured 38psi when empty as it should. I also released some air from the valve stem and got only air, no water. I’m happy to conduct additional tests to determine if the pressure tank is waterlogged, but so far I have no reason to believe this is the case.

Even if the tank was waterlogged it does not explain the large pressure delta I’m seeing, or the difference in pressure curves at the tank compared to the showers. I want to understand these before I consider replacing anything.

 

[Reach4]

1. With the pressure at maybe 50 psi and the pump not running, how does the air pressure compare to the water pressure gauge indication?
2. Is this a submersible or above-ground pump?

I did not watch your videos. How much time elapses between when the pressure switch turns on and the pressure starts rising?

EDIT: if the Shrader valve were on the bottom, it could serve as an indicator of water in the air area. With the valve on the top, the space above the diaphragm could be 90% full of water, and no water would come out of the valve.

Knocking on the side of the tank in the area above the ring where the diaphragm attaches could serve as an indicator. But for that, you would want to compare the sound with what it sounds like on a good tank.

 

[NoFortress]

1. When I drained the pump recently, the air pressure at the tank measured the same as the water pressure gauge. I’ll verify this again tomorrow.
2. Submersible pump.

Part of the reason I took the videos is because I’m not 100% sure exactly when the pressure switch engages. In the real-time video, the pressure slowly decreases to 50psi, after which the pressure drops nearly immediately to ~42psi, bounces around a bit, then drops to 30psi. Once it hits 30psi there’s an audible click and the pressure starts rising immediately. The drop from 50psi to 30psi takes about 8 seconds; the pressure starts rising immediately after the click at 30psi.

 

[Bannerman]

The pressure at the valve stem measures identically to the gauge I recorded, which I’d expect.

Your video seems to support a water logged tank as Valveman stated above.

Although the air valve maybe showing 38 psi after the water compartment has been drained, there could continue to be some amount of water trapped within the air chamber.

Water is not compressible, so water in the air chamber will displace some volume of air within the air chamber, and will also reduce the capacity of the water chamber. With less air being compressed into a smaller area, and with lower liquid capacity, pressure will rise rapidly while the pump is running. When there is water demand while the pump is not running, pressure will fall at a rate about equal to the rate of water consumption for as long as there is some water remaining in the tank, but as soon as there is 0 water remaining, then the water pressure will suddenly drop to 0 psi.

With insufficient capacity, the water chamber seems to be completely drained while the remaining air within the air chamber continues to be compressed to ~50 psi. Once the water chamber is empty, the diaphragm will be pressed against the bottom of the pressure tank, so the remaining compressed air can no longer push water out from the tank, therefore, the water pressure will immediately drop to 0, faster than the gauge can indicate.

Although a properly calibrated 40/60 pressure switch will activate the pump when it senses 40 psi, with 0 remaining pressure from the tank, the system pressure will have actually, briefly dropped to 0 psi before the pump becomes activated.

also released some air from the valve stem and got only air, no water

I suspect the air valve is located on top of your pressure tank. As such, the air chamber could be 80% filled with water, yet not have any water exit from the air valve. Suggest disconnecting and moving the completely drained tank to establish if any water continues to be contained.

Although there seems to be 50 psi remaining when the water chamber becomes empty, the remaining 50 psi compressed air will cause some of the water within the air chamber to be pushed back out through the source of the leak, thereby causing the air pressure to be further reduced over time. With a reduced volume of compressed air in the air chamber, not much water would need to exit to cause the pressure to fall from 50 to 38, and potentially to 0 psi if given sufficient time.

 

[Fitter30]

Have a bicycle pump. Ex tank let all the air out with pressure on the waterside get any water out of it more that 1 oz tank probably staring to fail. Turn pump off open a faucet drain system water gauge go to 0. If not replace the gauge. Use bicycle pump to air to tank 48 lb. Turn pump back on. Using a air compressor for the bladder can over pressurized it and might blow it.

 

[Reach4]

Pressurizing a pressure tank with a typical bicycle pump would be a lot of work.

 

[Valveman]

The gauge dropping quickly from 50 PSI means there is really 50 PSI in the air chamber. It should measure 50 PSI with the tire gauge when the pump off and faucets open. The air chamber gets to 50 from the original 38 PSI air charge when water gets through the diaphragm to the air side. If you want to see the water, remove the valve core from the scharder on the tank and turn on the pump. You will see water come out the schrader after the air on top of it gets out.

When there is no air cushion in the tank, the pressure delta at the showers will be more extreme.

 

[NoFortress]

Alright, I think everyone has collectively convinced me the pressure tank may be waterlogged. Thanks for the explanations there. I currently have a medium sized pressure tank; I'm guessing it's a 32-gallon based on dimensions but there's no markings on it otherwise. I have a family of 5 and suspect I need a larger tank. Would an 86-gallon tank be a good fit here? I also plan to upgrade to a 50/70 switch based on an above comment.

I've been reading about the cycle stop valve as well. It seems like it would work well for showers, but I'm concerned pairing it with a very small pressure tank (the linked one above was 4.5 gallons) would cause an excess of on/off cycles at the well pump from small uses of water (washing hands, washing dishes, flushing toilets, etc). And similarly, pairing it with a large pressure tank (e.g. an 86-gallon) would mean it rarely has a chance to kick in. Am I understanding this correctly?

 

[Sarg]

Suggestion : Believe & follow advice given by Valveman.
(Also just to mention ..... the 1/4 inch pipe nipple that connects your pressure switch to your system might be partially clogged with crap causing "irratic" operation. Just mentioning it because of personal experience.)

 

[WorthFlorida]

I’ve been on this forum for over 12 years, Valveman know his stuff. With a CSV, a small tank is needed, not a 86 gallon tank. Look at the CSV video’s. With a CSV the pump will not cycle but continuously run with a steady pressure until all water is turned off and the pressure switch shuts off the pump.

With a well you want the water to stay in the ground unless you have a chlorinator or other treatment tanks.

 

[Valveman]

Thanks Sarg! Only been explaining this for 30 something years so far. But I am glad there is someone new to explain it to everyday. Watching a few of our videos might help, as it is a show me kind of thing. But long explanation made as short as I know how, the pump will cycle the same number of times with a 32 gallon size pressure tank or a CSV and a 4.5 gallon size tank. Increasing the tank size used with the CSV just a small amount can decrease the number of cycles far more than the largest tank you can get. But even with the 4.5 gallon size tank, the CSV makes sure there is no way the pump cycle excessively. A little larger tank with the CSV like a 10 or 20 gallon size won't hurt. But the trade off is that you have to wait longer (until the tank is empty) before you will see the strong constant pressure from the CSV. With a family of five and using a 50/70 switch setting, I would use the 10 gallon size pressure tank like comes in the PK1A kit.

Custom PK1A PSIDE-KICK Pressure Tank Kit

Replaces large pressure tanks. Preset and easy to install for the DIY customer. The pside-kick kit is a complete constant pressure control package for most pump systems with demands from 1 to 25 gpm. This kit comes with everything you see and utilizes a mechanical pressure switch.

cyclestopvalves.com

 

[NoFortress]

I've watched the videos. It's obvious to me that for large uses of water (e.g. a long shower) the CSV will result in fewer cycles of the well pump. However, for frequent small uses of water it seems like the opposite will be true. Imagine someone washes their hands once every 10 minutes, using a gallon each time, with no other water usage. The 4.5 gallon pressure tank will cause the pump to cycle every 10 minutes (assuming it holds 1 gallon of water like your video states), whereas the 40 gallon pressure tank will only cycle once every ~2 hours (assuming 10 gallons of water like your video states).

The question is now whether the benefits from showers outweigh the downsides of hand washes and truly result in fewer daily cycles. It's just not obvious to me this is the case, as it seems like there are many more small uses of water per day than a long-running shower. It would be useful if you stated your assumptions for the average daily cycle table you posted.

 

[Reach4]

Lawn watering is the longest-usage.

Toilet flushing is another short-term usage.

 

[LLigetfa]

The 4.5 gallon pressure tank will cause the pump to cycle every 10 minutes (assuming it holds 1 gallon of water like your video states), whereas the 40 gallon pressure tank will only cycle once every ~2 hours (assuming 10 gallons of water like your video states).

Use the CSV in combination with a larger tank if it concerns you. You are not limited to a 4.5 gallon tank.

 

[Bannerman]

Hand washing usually occurs along with other water use activities such as toilet flushing, teeth brushing or meal prep.

The average reduction for cycling is in consideration for all water water use activities. Your pump may now cycle 12 times during each shower, or 200 times while watering the lawn, so with reducing those activities to 1 cycle each, a few additional cycles for hand washing continues to result in a large overall cycling reduction.

Even while using a tank that stores only 1-gallon, once the pump is activated, it's minimum run time will be 1-minute as the CSV limits tank fill to 1 GPM. If water is again utilized before the pump shuts off, that will reset the 'timer' so the pump will continue running for a further 30-60 seconds after no water is utilized.

If you want some additional capacity, suggest utilizing the 10-gallon pressure tank. This will supply 2.5 gallons before the pump will be activated, and that quantity will be consumed rapidly enough during larger water use activities such as showering, for constant pressure to be enjoyed during the majority of the shower.

 

[LLigetfa]

Even while using a tank that stores only 1-gallon, once the pump is activated, it's minimum run time will be 1-minute as the CSV limits tank fill to 1 GPM.

If the CSV is configured at the midpoint of the cycle, ( 50 PSI on a 40/60 switch) only about half of it will be at 1 GPM. The first half will fill at the max rate the pump can produce after satisfying demand. What that equates to in time may depend on the pump curve.

 

[NoFortress]

Use the CSV in combination with a larger tank if it concerns you. You are not limited to a 4.5 gallon tank.

Sure but, as I asked earlier, doesn't the larger tank somewhat defeat the purpose of the CSV? I believe Valveman himself said the same in a previous comment. If I have a 2.5gpm showerhead and a full 86-gallon pressure tank (holding 21.5 gallons of water), the well pump wouldn't kick on until almost 9 minutes into a shower. Then the well pump (mine is 10gpm) would take over 2 minutes to refill the tank. Odds are the CSV isn't even going to kick in during the average shower with a larger tank.

Several people mentioned lawn watering. That's not something I currently do, and I have no plans to do in the future.

I'm trying to compare a large 86-gallon pressure tank to a small tank with a CSV. The small tank has the benefit of mostly eliminating pressure fluctuation for showers (except for the initial drain and fill), but it seems to me it will result in many more pump cycles throughout the day with the exception of showers. With my above math, an 86-gallon tank should only cycle once during an average shower anyway (the same as a small tank with a CSV). If I assume my family uses an additional 100 gallons of water sporadically throughout a typical day outside of bathing, the CSV setup will cycle the well pump ~100 times for a 4.5 gallon tank or ~40 times for a 10-gallon tank. The 86-gallon tank will only cycle the pump ~5 times.

Am I understanding this correctly?

 

[Bannerman]

The first half will fill at the max rate the pump can produce after satisfying demand.

While technically correct, I haven't seen similar 'corrections' openly posted when Valveman has made the same statement in previous threads.

A further technical clarification, a 4-gallon tank is not offered with the PK1A PSide-Kick kit, but a 4.5 gallon tank is.