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WATER PUMPS, TANKS, TESTS, WELLS, REPAIRS
WATER CONTAMINANT LEVELS
WATER HAMMER NOISE DIAGNOSE & CURE
WATER ODORS, CAUSE CURE
WATER PUMP REPAIR GUIDE
WATER PRESSURE LOSS DIAGNOSIS & REPAIR
WATER PUMP SHORT CYCLING
WATER SOFTENERS & CONDITIONERS
WATER TANK REPAIR PROCEDURES
WATER TANK: USES, TROUBLESHOOTING
WATER TESTS, CONTAMINANTS, TREATMENT
WATER TREATMENT EQUIPMENT CHOICES
WELLS CISTERNS & SPRINGS
WELL FLOW RATE
WELL WATER PRESSURE DIAGNOSIS
WELL YIELD IMPROVEMENT
WINTERIZE A BUILDING
Well pump pressure control switch adjustment: This article describes How to Find & Adjust or Repair or Replace the Water Pump Pressure Control, what it looks like, where it is usually connected. If you need to adjust water pressure at a building served by a private pump and well system, or if your well pump is acting badly, this pressure control switch may need adjustment or repair/replacement.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
In the sketch above the pump pressure control switch is item #4 - we show this switch in more details in photographs provided below. Readers of this document should also see Water pump and pressure tank repair diagnosis & cost an specific case which offers an example of diagnosis of loss of water pressure, loss of water, and analyzes the actual repair cost.
If your building water supply is from a municipal water main rather than a private well, see WATER PRESSURE REGULATOR ADJUSTMENT.
A Guide to Building Water Pressure by Adjusting or Repairing the Water Pump Pressure Control Switch
If the water pump "short cycle" is very short, clicking on and off, there could be a shortage of air in the water tank, or there could be a problem with the pump control pressure switch itself, or even a dirty and clogged water filter if one is installed on the system. Dirty water filters and other causes of rapid water pump on-off cycling are discussed at CAUSES OF SHORT CYCLING.
These water pump short cycling problems happen with both in-building jet pumps and with in-well submersible pumps. It's trickier to notice
a short cycling submersible pump since you won't hear the pump motor, but you will hear the pump relay clicking on and off, or
you can see the water pressure gauge cycling up and down rapidly.
A defective water pressure control switch. Switch contacts can burn-up, or the opening into the switch
which senses the water pressure in the system can become clogged with sediment or debris. This usually
shows up as failure of the pump switch to turn on or off at all, rather than short cycling. But the switch could be damaged or improperly adjusted, causing "short water pump cycling."
Details about this switch are at WATER PUMP PRESSURE CONTROL SWITCH
Technical note: Clogging of the Water Pump Pressure Control Switch if your water has a high level of silt, debris, or minerals, it's possible that the tubing or piping connecting the pump pressure switch to the pump or water piping (red arrow in photo at left), or the pump switch bottom orifice through which the pressure switch senses the water pressure in the system has become clogged.
The small diameter of this tubing and still smaller diameter of the pump switch orifice makes clogging easy if your well water is high in sediment or minerals.
On rare occasions we can tap on the well pump control switch and it will begin working again, but not for long, and not reliably. Another water pressure control switch failure is the rupture of a rubber disk or "bladder" inside the switch itself. If you detect or suspect a defective pressure control switch, try replacing it with a new one.
We see a similar problem affecting water pressure gauges on private water systems: debris or mineral deposits can clog the pressure sensing orifice on the water pressure gauge, causing it to fail to respond at all, or to respond inaccurately to changes in water pressure.
When we find a clogged water pump pressure switch or the tubing connected to it, or a clogged water pressure gauge, we replace those items. A well pump pressure gauge that does not respond to pressure changes is potentially unsafe as it could lead to excessive pressurization of the water tank and building piping.
Watch out: some pump pressure control switches may mount directly to a water pressure tank without an obvious 1/8" or 1/4" ID mounting tube. In our pressure switch photo at left the red arrow points to the mounting base for the pressure control switch and you'll see that this control was screwed right into the water tank at a threaded tapping.
But the pressure sensing membrane found on the bottom (or in this case on the left side in our photo) of the pressure control switch can still become damaged or the orifice that admits water (and pressure) is easily clogged. The effect of debris clogging at a water pump pressure control switch is the same regardless of whether or not a longer mounting tube is used to mount the switch to the water system.
Frequently Asked Questions (FAQs) about about well pump pressure control switch inspection, installation, diagnosis, & repair
Question: What should I do about sudden very high water pressure in my pump and well system?
I noticed that my water pressure suddenly seemed awful high and when I checked the gauge it was. I have a 6" drilled well and the shutoff pressure was reading 80# of pressure. I tried adjusting the range nut with little success. The gap between 'on' and 'off' was way to much. (The switch, a Square-D, indicated a gap of 20-40 ) I think that I have a bad pressure switch. Any thoughts? - J.T.
Reply: Replace the pressure control switch, check and clear debris blockage in the switch mounting piping
A competent onsite inspection by an expert usually finds additional clues that help accurately diagnose a problem.
That said, here are some things to consider based on what you've described so far:
Because you confirmed that the water pressure really is excessive by direct observation, I don't think this is a common gauge error problem and I agree that the problem is most likely with the pressure control switch. In our photo (above-left) the green arrow points to a SquareD pump pressure control switch at its typical installation location.
A well water pump pressure switch might stick in the "on" position due to debris clogging at the pressure sensing orifice, or at the switch mounting tube, or on occasion relay switch points can burn and actually weld together.
Turn Off Unsafe Water Pumps
Watch out: high pressures from a pump that is either pumping to too high a pressure control setting or that does not shut off due to a switch or wiring problem can burst water pipes or a water tank, possibly even leading to injuries, especially if your water pressure tank lacks a pressure relief valve. I would turn OFF a system pumping to or over 80 psi until the problem is diagnosed and corrected. In our photo (above left) there is indeed a pressure relief valve installed on this pump and tank system. You can see the relief valve attached just below the pressure switch mounting tube (red arrow).
How to Install a New Water Pump Pressure Control Switch
If no one had previously been attempting to adjust the pressure control switch, I'd install a new one. When you install the new switch, either replace or clean out the small-diameter (typically 1/8" or 1/4" ID NPT) pipe nipple that is used to mount the pressure switch to the piping or fitting where it is attached. In our pressure control switch photo (above left) the red arrow points to the mounting tube that we are discussing.
Watch out: As a temporary, emergency "Sunday night" repair, I have filed clean and smooth pitted, burned contact points on a relay switch (with power OFF of course), but because relay switch points are made with a protective plating on the contact point surfaces, when you file or clean burned contact points the switch may still have a short remaining life, and you risk also changing the behavior of the contact relay or even of making the switch unsafe. So it's best to replace the switch promptly.
To replace a water pump pressure control switch the installer will need to turn off electrical power to the system, remove the old switch by disconnecting its wiring and then unscrewing the switch from its mounting tube, and install the new switch in the same position. It's a good idea to label your switch wires or take some photos as well so that you wire the new switch exactly as the old one was hooked-up.
Watch out: if you do not run enough water to remove water pressure from the pressure tank, when you remove the old pressure switch you'll see water squirting out of the mounting tube. That's not necessarily so terrible if that "squirt" also cleans debris from the tube. If you drain off water pressure first, the leakage at that point will be trivial. If not, be prepared to get wet as you are screwing the new switch in place, and be prepared to dry everything out before restoring electrical power.
Don't forget to use teflon paste or tape on the threads of the mounting tube so that your new switch won't leak at the mount, but don't blob in so much pipe dope or paste that you risk clogging the switch pressure sensing orifice on the switch bottom.
You should be able to use the new pressure control switch with the factory settings for cut-in and cut-out pressure, especially if you bought one already set to one of the two standards: 20/40 psi or 30/50 psi for Cut-in and Cut-out pressures. Or see WATER PUMP PRESSURE CONTROL ADJUSTMENT if you need to adjust the pressure switch settings.
Check for Sediment Blockage at the Pump Controls
As we discuss at Water Pump Pressure Control Switch Tubing Problems, often if there is sediment or rust or debris in the water system, that small diameter pipe or even the bottom sensor openings on the pressure control switch can become clogged. The result is that the switch stops properly sensing water pressure.
At that point pressure switch behavior can go either way: the switch may fail to sense a water pressure drop and thus doesn't turn on when needed, or it may fail to sense a water pressure increase and thus does not turn off when needed. Too little water pressure is inconvenient. Too much water pressure can be dangerous.
If/when you are replacing a pump pressure control switch, check the tubing or switch mount as well as the bottom of the old pressure switch for evidence of sediment or mineral deposits or other crud that block the pressure sensing mechanism. Clean or replace blocked switch mounting tubing.
Install a Sediment Filter?
Finally, if indeed your water source is giving up debris, silt, or other sediment particles that can clog the water supply system and its controls, you should consider installing a water filter system as well. Most water filters I've seen are installed after, rather than ahead of the water pressure tank and controls. But if needed, with a few extra control valves to make filter changeout easy, it should be possible to install filtration ahead of the tank and controls, thus protecting them from sediment as well.
Identify Old Pressure Control Switches?
Question: Can you identify the manufacturer of this water pump pressure control switch on a mobile home?
Question: Why won't the pressure control switch cut-on at low pressure?
Water tank is set at 50/70 why wont it cut on at low pressure - it only clicks like missing its starting point .
We had points replaced last year but it still wont start (kick on) we had left home for a week and only cut water supply off to house and cut off hot water heater - now it wont work right - Barry.
Reply: Check for a clogged or blocked sensor on the pressure control switch - replace the switch assembly
If your pressure switch is not turning the water pump on it could be a clog in the pressure sensor switch or its mount, or you need a new switch. Often debris in the water supply clogs the small orifice on the bottom of the pressure control switch. That orifice is intended to allow water (or air) pressure in the water piping to press against a diaphragm that operates the pressure control switch.
In sum, if your prior repair replaced just the internal points assembly in the pressure switch, the switch may be old enough that its sensor is clogged.
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