water pressure from well

[RustyShackleford]

My house is on a well. About 30 years old. Never had any problems except once lightning blew up the submersible pump. No serious problems now.

But, after a kitchen remodel, I notice the faucets are putting out pretty low flow. I measure a little shy of 1gpm. I realize that energy conservation has become a big thing since the original construction, but still, they are rated for 1.5gpm, although that's at 60psi, and they don't give a graph of flow versus pressure.

Anyhow, I notice the gauge on at the well's pressure tank (in the crawlspace) only reads about 30 psi or so. Wondering if I should: replace the gauge and/or the pressure switch, adjust the pressure switch for more pressure, or what. I imagine the first thing is to replace the pressure gauge, to make sure I know where I'm really at - 30 years seems pretty old for something like that and they're only $10 or so. I also wonder how much water pressure is considered "safe". I replaced all the crawlspace plumbing with crimp-ringed PEX recently, but unfortunately I had to install adapters to the polybutylene (aka. Qest) pipes that come down out of the walls from the various fixtures. Those would be a pain to upgrade, though more of a pain if they fail. So the Qest is probably the limiting thing on how much pressure is safe.

Oh, and I'm pretty sure the pipes themselves are not the problem, as I was pretty careful about sizing when I replaced everything in the crawlspace with PEX. Also, a hose bib comes off the 3/4" line that goes to the kitchen (which is where I'm really noticing low flow) and that hose bib gives fine flow.

 

[tadmaz]

Is your pressure switch 30-50, or 40-60psi?
Try this:
-Turn off breaker to well pump, shut off water to house.
-Drain pressure tank via schrader valve, pressure gauge should go down as you do this until it gets to 0.
-If your switch it 30-50, using an air compressor fill pressure tank to 28psi (2 below "cut-in")
-If your switch it 40-60, using an air compressor fill pressure tank to 38psi (2 below "cut-in")
-Turn on breaker to well pump
-Note how high it gets, then run some water from a nearby faucet and note how low the pressure gets until you can hear the pressure switch click (starts the well pump) This is the "cut-in" psi your pressure switch is set to.
-Turn off the nearby faucet, and note how high the pressure gets to when the pressure switch clicks off (well pump is off). This is your cut-out pressure.
-Adjust your pressure switch so that the cut-in is 30 or 40, depending on your switch style, and adjust the cut-out to be 50 or 60, depending on switch style. It's easier said than done. Usually a deep 3/8" socket on a ratchet is what you need, the middle nut is your cut-in, the one of the side is the cut-out. May be lots of trial/error/faucet running. Clock-wise raises pressure, counter-clockwise lowers pressure. Adjust the cut-in first, as the cut-out is dependent on the cut-in!
-Also bang your wedding band on the pressure tank after all of this, should sound completely hollow (air), versus a dull thud (filled with water). Check on this after a few days, maybe the bladder has a hole and eventually gets full of water.

 

[RustyShackleford]

Thanks for the comprehensive write-up. Yeah, I have never checked the charge in the pressure tank. Seems to me like before I do any of the process you recommend, I should first replace the pressure gauge, no ?

 

[tadmaz]

I was replacing my pressure gauge a few days ago since it was stuck, it actually got un-stuck as the pressure got below 10. Seems to be working fine again. In any case, a new pressure gauge is $7 at Menards/Fleet Farm. If you take the charge off the pressure tank and the gauge is still stuck at 30, definitely just replace. Really hard to diagnose any issue without a working pressure gauge.

 

[peakbagger]

Precharge tanks do lose pressure over the years. I probably need to do the same checks on mine.

 

[Wooden Head]

The air gauge you use for testing is important. I have found the accuracy of some to be as much as 10 lbs. in a 40 PSI range. Also, I have had new kitchen faucets that were horrible with pressure. The last one was a off-brand from Menards that cut pressure in half and when the washing machine ran hot water the kitchen faucet would only dribble hot water. Changed to a Moen and everything works as it should. Both flow and pressure.

 

[sportbikerider78]

Buy yourself a nice tire pressure gauge for your car and then use that on the pressure tank as well.

Remember, cheap gauges (almost all are cheap) have error 5-10% of FULL SCALE. So if you have a 0-100 psi gauge, you are somewhere between 5-10 psi off. Get a cheap gauge that reads 0-60 or 0-50 and you have eliminated half of your full scale error.

 

[Ashful]

Buy yourself a nice tire pressure gauge for your car and then use that on the pressure tank as well.

Remember, cheap gauges (almost all are cheap) have error 5-10% of FULL SCALE. So if you have a 0-100 psi gauge, you are somewhere between 5-10 psi off. Get a cheap gauge that reads 0-60 or 0-50 and you have eliminated half of your full scale error.

Well, that... and remember that any rotary gauge is calibrated for best accuracy at 30% - 70% of full scale. If you’re trying to get an accurate reading on a 30 psi tank, you’d do well to find a gauge that measures 0 - 60 psi.

Even with that said, any three different brand $15 tire gauges at the auto parts store will give you three different readings, sometimes by as much as 20%, IME.

 

[tadmaz]

On the topic of tire pressure gauges, I have a Slime brand digital gauge, and I can get within a tenth of a PSI when filling the car tires. While who knows if it's accurate, it will at least give me consistent pressures between all tires. Some tires that I have plugged will very slowly lose air, and I can tell since 3 tires will be within a tenth of each other, and another may be 1.8 PSI lower for example.

 

[semipro]

@RustyShackleford IIRC you'e an EE. I'm not sure about your experience with hydraulics but as you work through this issue it may help to think of pressure as voltage and flow as amperage. The product of voltage (pressure) and amperage (flow) are power (W, hydraulic HP). Thinking about that way should help with diagnosis.
Thinking of your pump as a generator, your tank as a capacitor, and your pressure gauge as a voltmeter may help.
It this sounds patronized its not meant to. I just really appreciate the analogue between electrical and hydraulic systems.

Edit: By chance did your plumbing work loosen some mineral deposits that have clogged the aerator screens in your kitchen faucet?

 

[semipro]

Even with that said, any three different brand $15 tire gauges at the auto parts store will give you three different readings, sometimes by as much as 20%, IME.

2nd that. I observed this very thing last weekend. Its almost like you need a manometer to get an accurate reading.

 

[Highbeam]

We should talk accuracy vs. precision!

 

[marco nunes]

I'm no well expert ,but if your pump has been replaced and you have not played with any of the cut off and on switches adjustments you should be ok.The gauge is feed by water psi to work correctly and the line going from the pump to the gauge is blocked up with junk your psi and gauge will not read correctly,result in low pressure. Try to find the line off the gauge follow it back to the pump,you should have a screw fitting threaded into the pump.unscrew it take a thin piece of wire and clean the port in the pump it's probably clogged up ,just make sure you cut the power before you try this you don't want the pump to turn on good luck.

 

[zrock]

if its only the taps you replaced that have lost flow then its your taps that are the issue.. Any new taps we get i remove the restriction plate at the end of the tap and problem solved.. Some i have had to take a drill and drill out the restriction plate.

 

[RustyShackleford]

Well, that... and remember that any rotary gauge is calibrated for best accuracy at 30% - 70% of full scale. If you’re trying to get an accurate reading on a 30 psi tank, you’d do well to find a gauge that measures 0 - 60 psi.

Very discouraging, but that's a good tip to make full-scale as low as possible.

@RustyShackleford... it may help to think of pressure as voltage and flow as amperage.

Actually I did my graduate research modeling the airways of the respiratory system as electrical analogs, so I'm pretty down with that, and yeah, it's helpful indeed to think of it that way.

Try to find the line off the gauge follow it back to the pump,you should have a screw fitting threaded into the pump.unscrew it take a thin piece of wire and clean the port in the pump it's probably clogged up ,just make sure you cut the power before you try this you don't want the pump to turn on good luck.

I'm not quite following. The pump is 150ft below the ground; maybe you're thinking I have a jet pump ? Still, I guess it could be some restriction between the pressure tank and the gauge and/or pressure switch.

if its only the taps you replaced that have lost flow then its your taps that are the issue.. Any new taps we get i remove the restriction plate at the end of the tap and problem solved.. Some i have had to take a drill and drill out the restriction plate.

It seems to be all the taps I've replaced since flow restrictions were put in place (IOW, not including the ones installed when the house was built 30 years ago). Where do I find these restriction plates ? Above the aerators ? It may simply be that these faucets are designed for 60psi (that's what the gpm on them is spec'd at) and I don't have it. And I dunno if it's safe to increase my pressure, particularly with the old polybutylene/Qest going up into the walls.

 

[Ashful]

Very discouraging, but that's a good tip to make full-scale as low as possible.

Not as low as possible. If you select a 30 psi gauge to measure 30 psi, it will be at its worst accuracy. You want a gauge with a full scale of 45 - 90 psi, which puts your 30 psi measurement in the middle third of the range. Ideally, a 60 psi gauge is calibrated at 30 psi.

 

[OT_Ducati]

Unscrew aerator and there it is. Pop it out.

 

[peakbagger]

Unscrew aereator with the sink drain plugged and take good notes. The aerators frequently have a screen and a few diffuser plates with o-rings and other bits. In order to clean them out they should be disassembled and then reassembled correctly and its real easy to drop parts down the drain.

Note that they may require using a pipe wrench to unscrew them especially with hard water.