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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
This article describes How to Repair a Water Pressure Control Switch that Sticks "ON" or "OFF" or is irregular in cycling on and off.
In the sketch above the water 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 PUMP PRESSURE CONTROL REPLACE and WATER PUMP PRESSURE CONTROL ADJUSTMENT. And at WATER TANK BLADDER PRESSURE ADJUSTMENT we discuss fine tuning the pump pressure control switch to work perfectly with the exact air pressure pre-charge in a bladder type well tank.
Separately we provide a WATER PRESSURE PROBLEM DIAGNOSIS TABLE in table format listing nearly every cause of water pressure loss or well pump problem identification, diagnosis, and repair.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
Frequently Asked Questions (FAQs)
Questions & Answers about diagnosing, repairing, or replacing a well pump pressure control switch
Question: how do I replace the well pump pressure control switch shown in this photo?
There is no such tubing [visible] on my system (see the photo at left), yet switches I looked at, at HomeDepot.com mention "1/4 in. pressure connection".
Am I going to run into a problem if I don't have this tubing? Can I still use such a switch? Here is a picture of back of the pressure control switch.
Reply: You'll be fine with a new pressure control switch, a close nipple (iron pipe thread) of brass or galvanized steel, and some teflon pipe tape or pipe sealant.
It looks like your switch a 1/4" rather than 1/8" diameter iron pipe though I'm not quite sure from just the photo. Larger diameter gauge and pressure switch mounting pipe means less likely for the pipe itself to clog with sediment, rust, debris. But the principle is the same.
The reason you don't see a "tube' or mounting pipe is that your pressure switch connecting base (red arrow in photo above) is screwed directly into that galvanized iron tee (green arrow), almost certainly using a "close nipple". See our brass close-nipple photo at left and see the white marking line in photo above showing where that part is hidden.
A close nipple is nothing more than a very short section of threaded pipe. (photo at left). For comparison, here is a photo of a standard pipe nipple, also made of brass in this case. You can see another close nipple in your photo above - between the galvanized pipe tee and the metal to plastic bushing that adapts the whole setup to fit into that white plastic fitting (between the green and yellow arrows in our annotated photo).
When you unscrew the pressure control switch from the pipe tee shown in your photo, the close nipple will either come out with and remain attached to the switch bottom or it will remain screwed into the tee. If the close nipple remains screwed into the tee and does not move at all, you may be able to screw the new switch right onto it.
Watch out. If the close pipe nipple moves in the tee but you try just leaving it in place you may have a leak when you repressurize the system.
To change out the pressure switch shown in the photo above, you'd turn off power, remove wiring from the switch, drain pressure off of the water pressure tank to reduce the spillage when you remove the switch, then carefully unscrew the switch (attach a wrench to the fitting on the bottom of the switch) from the pipe. I'd probably use a small pipe wrench or Vise-Grip™ tool to remove the old close nipple from whichever side of the fittings it remained, and I'd install a new one to be sure my installation didn't leak.
Your plumbing supplier can supply you with both a threaded pipe nipple of the proper diameter and a new pressure switch (whose bottom typically includes a mounting fitting sporting a female NPT threaded fitting intended to screw onto a pipe, tube, or close nipple). (Some pressure switches might be supplied with a male threaded bottom fitting instead of female - check the parts before you leave the supplier so you have what you need to make the new connection.)
Watch out: because your whole setup of switch and gauge are mounted in a larger diameter PVC plastic pipe fitting (yellow arrow in photo above), if the switch is hard to unscrew you risk breaking that plastic part - which would mean more work to repair the system. Avoid this problem by using two wrenches, one holding the metal pipe tee into which the switch base is screwed, and the other turning the switch base against the tee. That will avoid stressing and breaking the plastic.
Use a bit of teflon tape or pipe dope when mounting the new switch but don't blob pipe dope or tape into the switch bottom where it might block the sensing switch diaphragm orifice.
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Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.
Water Supply & Drain Piping, Wells, Pumps, Water Supply Equipment