(206) 949-5683, Top Rated Plumber, Seattle
Results 1 to 9 of 9

Thread: pressure extremes

  1. #1

    Default pressure extremes

    I've been reading posts and haven't seen this problem: 2 nights ago had no water, later discovered the black plastic pipe had disconnected from the wellhead. I reconnected the pipe and now the problem...the pump is not kicking in until about 10psi, seems to stop pumping between 50 & 60 psi, but the (relay?) switch stays on, the gauge quickly -in 4 to 5 seconds- goes up to between 90 and 100 plus, the switch stays on a few more seconds, then stops. This may not be related to the pipe problem, it may have been working like this for a while but we didn't notice - or look at - the gauge until then.
    Is the pressure really going to 100 psi, or is the switch or gauge just not working properly?
    If it is going up to and over 100 psi, can this thing blow up?
    Since the pump is working, can I (hopefully) assume that is not the problem?
    Thanks for listening, hope someone can shed some light.
    John

  2. #2

    Default

    Have you noticed a huge increase in the pressure at the house? If not, I would assume that the gauge is bad. Replace it (they're really cheap) and then see what the pump is doing.
    Ron

  3. #3

    Default

    Thanks Ron, haven't noticed any change in pressure. As to replacing the gauge - since there's no shutoff before or after it, can it be unscrewed without water running out of the opening? Do I need a specific gauge or are they generic? Thanks

  4. #4
    Retired Defense Industry Engineer jadnashua's Avatar
    Join Date
    Sep 2004
    Location
    New England
    Posts
    21,388

    Default

    Okay, I'm not a pro, but consider this. If your pressure tank's pressure is too low, the bladder compresses slowly as you fill it up (which is normal), and then almost reaches the maximum compression - spiking the pressure. Think of the air as a spring. All is well until you compress it fully - more pressure, no more compression, the pressure can jump quickly. If the tank has enough air pressure in it, the pressure builds slowly, and there is still room for expansion once it reaches the upper limit. Check your expansion tank to make sure its bladder is not shot, and that it has about 1-2# LESS than the low-pressure turn-on point. You have to do this with the pump off, a valve open to relieve all pressure in the system. If you get water out of the fill valve, replace the tank.
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

  5. #5

    Default

    Thank you Jim. I'm not sure where the low pressure turn on point is. It has been kicking in anywhere from 5 to 15 since I've been watching it. And the water from the faucets does slow noticably until the pump starts up. As I've mentioned the turn off point seems to be between 50 & 60.
    Since these numbers seem quite erratic should I try to adjust the pressure switch to a more normal range before I test anything else, or should I just replace it. If the switch is at least part of the problem the cost of a switch, in the $20 range, seems reasonable and I worry that adjusting the existing one may only be a temporary fix.
    Or am I totally wrong suspecting a problem with the switch? The chicken & egg thing - is the switch making the pump work erratic or the other elements causing the switch to work erratically
    Last edited by jcsyw; 07-13-2005 at 03:06 AM.

  6. #6
    Moderator & Master Plumber hj's Avatar
    Join Date
    Aug 2004
    Location
    Cave Creek, Arizona
    Posts
    25,624

    Default pressure

    I would check further before changing the gauge. If the pressure is really going to 100 psi, possibly because the pump switch is defective or the pipe to it is plugged, then that could be the reason the pipe blew off of the pump connection.

  7. #7
    That's all folks! Gary Slusser's Avatar
    Join Date
    Aug 2004
    Location
    Wherever I park the motorhome.
    Posts
    6,790

    Default

    Assuming a submersible pump.... few jet pumps will build enough pressure to blow a line off them. Assuming it's not a 1 hp or larger jet pump.

    IMO the switch is not seeing the pressure in real time; it lags. Meaning there is blockage in the switch nipple or where it screws into the tank tee or plumbing or the switch itself preventing current pressure to the switch for both on and off of the pump. That allows the excessive pressure to blow off the line. Remove the switch from the nipple and run a screw driver down thru the nipple into the tee or pipe to clean any blockages.

    Then since you have to shut off the pump and the water to the house to do that, you then drain the water from the tank. Then check the air pressure in the tank and adjust it to 29-28 psi with no water in the tank. IMO you should replace the guage while doing this. If the switch is say 15-20 years old, I'd replace it too with a 30/50 psi switch. If you want 40/60, buy a 40/60 switch and set the air presure with no water in the tank to 39-38 psi.

    Your pump is in great shape.

    Gary
    Quality Water Associates

  8. #8

    Default

    thank you all, belatedly. was visiting the kids a couple days. I'll break out the tools, make a trip to the store for a new gauge & switch. But first -what may seem like obvious to you pros, but I'm afraid of just disassembling things blindly- to drain the tank, I see the spigot at the bottom but instead of a handle there is a plug with lines and numbers 125,150,175. Do I turn this out to open the valve? And next..I understand I can check the pressure with a tire gauge, right? but where exactly am I doing this? There is a red cap on top, do I remove that? I assume I can use an air compressor to put air in, so am I right in assuming there is a fitting beneath the cap. Sorry for asking what may seem simplistic questions, but I promised my wife I wouldn't use trial & error destructively anymore :-)
    Last edited by jcsyw; 07-15-2005 at 06:07 AM.

  9. #9
    That's all folks! Gary Slusser's Avatar
    Join Date
    Aug 2004
    Location
    Wherever I park the motorhome.
    Posts
    6,790

    Default

    Yes the air valve is under the red cap. I have no idea what drain valve you have, but if you can put a garden hose on it it's meant to drai nthe tank.

    Gary
    Quality Water Associates

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •