Pressure Tank losing pressure

Discussion in 'Pumps and Tanks Well Forum & Blog' started by epps, Sep 10, 2009.

  1. epps

    epps New Member

    Messages:
    9
    Location:
    Caputa, SD
    I have a 2K gal cistern and a H2ow-to pressure tank inside the house. It has been working fine until two weeks ago when our power went out repeatedly for a couple days. Each time it went out, we would have no water and would have to reset some switch on the tank, it looked like a screw with an allen wrench sticking out. This switch had to be reset a few times until you could hear water flowing through before we got water.
    Since then, the kitchen sink hasn't had much pressure, at least compared to the pre-power outage pressure. However it is a constant pressure. In the shower across the house, the pressure starts out great (just like pre-power outage), but within 3-5 minutes it decreases quite a bit. I've been reading quite a few forums, but I can't really find a problem similar to mine. Any advice? Thanks!
  2. valveman

    valveman Moderator Staff Member

    Messages:
    4,549
    Location:
    Lubbock, Texas
    So what kind and size of pump do you have? Are there any filters in line?
  3. epps

    epps New Member

    Messages:
    9
    Location:
    Caputa, SD
    I'm not sure on the specifics, I will take a look at it this evening. Is that what it is sounding like? I know it is a pump that sits on some tubing at the bottom of the cistern. I was told there are two filters in the line between the cistern and the supply. I don't know for sure though. I'll let ya know, thanks.
    Last edited: Sep 11, 2009
  4. epps

    epps New Member

    Messages:
    9
    Location:
    Caputa, SD
    It has a flotec 2212-08 pump in the cistern. The gauge shows 52 PSI right now with no water being used. Very little of the piping is exposed (the bladder tank is in a closet in the house), but it looks like there is one filter right before the water goes into the tank (or out). I believe its a filter, just a cylindrical attachment, looks like its made of brass?, and has a name plate on it. I can't get close enough to it to read the name plate.
  5. Gary Slusser

    Gary Slusser That's all folks!

    Remove any filter cartridges from any filter housings and see how it does then.

    That switch you think you adjusted with an Allen wrench, it probably wasn't a switch, it was probably a valve.

    Take and post some pictures of this stuff. That will help a lot.
  6. epps

    epps New Member

    Messages:
    9
    Location:
    Caputa, SD
    pictures

    I attached some pictures. Still no change in pressure. It's really wierd that this suddenly happened when the power went out. The bladder isn't ruptured. I've watched the gauge as the shower is being run, it drops down fast and is very slow to recharge as water is still being used. Also, what i thought was a filter looks to be a check valve (I can't get to it to read it but after i took the picture i can read the name plate). Any ideas? Where would other filters be?

    Attached Files:

  7. Bob999

    Bob999 In the Trades

    Messages:
    448
    Location:
    Pennsylvania
    You have not explicity mentioned whether the pressure showing on the pressure gage at the bladder tank is normal so that is the first thing to determine--do you have normal pressure at the tank.

    Assuming you have normal pressure at the bladder tank then the symptions sould like a restriction downstream of the bladder tank. Is the pressure problem on the cold line, hot line or both? Depending on the answer it will inform what lines you need to trace. You indicate there are no filters. What about valves that might be partially closed? Trace the water line(s) from the pressure tank to the kitchen sink and the shower to confirm no filter in either line and no partially closed valves.

    Do you have iron, silt, sand, or other matter in your water that may be creating a block downstream of the pressure tank? If so you may need to flush the line(s),
  8. Gary Slusser

    Gary Slusser That's all folks!

    Where is the thing you adjusted with an allen wrench?

    What does that plate say that brass part is?
  9. epps

    epps New Member

    Messages:
    9
    Location:
    Caputa, SD
    I never monitored the gauge under normal operation so I'm not really sure what to compare it to. As far as hot or cold, neither one seems to show much difference in pressure, so I would say it is common for both and up stream of the hot water heater. I believe there is a lot of Iron in the water I haul. It leaves red traces after sitting for a while. The brass part says it is a dual check valve or something to that effect. On the grey box, there is something that resembles an allen wrench sticking out, that is what i was turning on/off to reset the pump or whatever it was resetting to get water after the power would come back on. I can't find any filters in any of the exposed piping, but very little is exposed. I pulled off the screen filter on the end of the kitchen faucet and found some crap in it, which leads me to believe there are no filters from the cistern to the supply.
    Last edited: Sep 24, 2009
  10. Bob999

    Bob999 In the Trades

    Messages:
    448
    Location:
    Pennsylvania
    You said you found debris in the faucet strainer--did the pressure improve after cleaning? Id it did you should also check the shower head and clean/replace as necessary.

    If you still have a problem try this to help identify it:
    1. Check the pressure at the tank.
    2. Have a second person turn the water on at a problem location and monitor the pressure while you monitor the pressure gage.
    3. Compare your results--does the pressure gage at the tank drop when the pressure at the faucet or shower drops? It it doesn't there must be an obstruction.

    If the pressure drops at the tank when doing this test then the problem is with the tank or with the supply to the tank.
  11. Gary Slusser

    Gary Slusser That's all folks!

    There won't be any filters other than the faucet tip screens because they would have to be installed by the tank probably.

    The double check valve brass thing is a back flow prevention device. They are usually used on city water systems, not residential well water systems. It may be your problem if one of the check valves is sticking. And unless your pump's check valve is leaking you don't need it.

    The "gray box" is your pressure switch and the "allen wrench" thingy is a lever used to turn the switch On, to Auto (to restart the pump) or Off.

    The switch is a low pressure safety cut off switch and they are used to shut off the pump in low recovery wells that can go "dry". The purpose is to prevent damage to the pump if the water level in the well gets down to the pump's inlet.

    Your low pressure may be due to a low water level in the well and a pump that can't pump from lower levels of water.
    .
  12. epps

    epps New Member

    Messages:
    9
    Location:
    Caputa, SD
    I have noticed a better flow of water to the kitchen sink i believe. I pulled the head off of the shower (its a brand new head from this spring) and tried putting water through it backwards, then blew air through it, it didnt seem clogged, but still has weak pressure. I'll try the method you suggested tomorrow and see what happens, but it seems like it has narrowed down to something in the line between the supply and the shower.

    I had another problem today. I came home and there was no water. I went to that pressure switch and reset it a few times til i heard water flow and the gauge start to move. This happened 2 or 3 more times within a couple hours. We have a cistern and there was plenty of water in it. Are these common symptoms of the switch going out?
  13. Bob999

    Bob999 In the Trades

    Messages:
    448
    Location:
    Pennsylvania
    Check the flow of the shower with the head removed.
  14. Gary Slusser

    Gary Slusser That's all folks!

    It is a symptom that the pump is going out or something is blocking its inlet.

    You need to do or have someone else do electrical troubleshooting on the system but especially the pump motor. You need a volt/ohm meter and possibly an amp gauge if everything checks out.

    http://www.goulds.com/pdf/GSSINGLE.pdf
  15. epps

    epps New Member

    Messages:
    9
    Location:
    Caputa, SD
    I am an electrician (aircraft) and I have a multimeter. Are you thinking that something is clogging the pump (or the pump is going out) and tripping the cutoff switch? Its been doing this on and off again all day today. I am going to go out and pull the pump out of the cistern and check it out.
  16. nhmaster

    nhmaster Master Plumber

    Messages:
    3,189
    Location:
    S. Maine
    Most plumbing codes require a backflow preventer on all potable water systems whether public or private.
  17. Gary Slusser

    Gary Slusser That's all folks!

    Yes I am because the switch (a low pressure safety switch) opens when the water pressure falls to like 20 psi. You need to find out why the pressure is falling that far before the pump comes on or, why the pump comes on and the pressure still falls to like 20 psi and the switch opens which shuts off the pump.

    I have never heard of a back flow preventer being required on a private well or a residential type commercial well, so check your code and if it is not required, if it were mine I would remove it because there is a foot valve or check valve in the well.
  18. nhmaster

    nhmaster Master Plumber

    Messages:
    3,189
    Location:
    S. Maine
    The check valve at the pump is in a location that were it to fail would allow the entire contents of the water system, including the water heater to drain back into the well, thereby contaminating not only the well buy possibly the entire aqua fir. Leave the BFP, its cheap insurance and is not the cause of your problem. Either the well is going bad or the pump is going bad. Removing it is the kind of bad advice you get from folks that are not licensed plumbers and don't understand the hazards of back flow.
  19. Bob999

    Bob999 In the Trades

    Messages:
    448
    Location:
    Pennsylvania
    Your comments seem somewhat at odds with the information posted in the sticky about multiple check valves.
  20. nhmaster

    nhmaster Master Plumber

    Messages:
    3,189
    Location:
    S. Maine
    The backflow preventer is on the pressure side beyond the pressure tank, or it should be anyway.
Similar Threads: Pressure Tank
Forum Title Date
Pumps and Tanks Well Forum & Blog Dielectric union at pressure tank or not ? Nov 17, 2014
Pumps and Tanks Well Forum & Blog City water + cistern + booster + pressure tank thoughts Oct 17, 2014
Pumps and Tanks Well Forum & Blog Setting pre-charged tank pressure Oct 14, 2014
Pumps and Tanks Well Forum & Blog Question on new pressure tank install.. outside barn hydrant Sep 13, 2014
Pumps and Tanks Well Forum & Blog Loud thud/slapping noise after well pressure tank cut off at 60 psi Sep 11, 2014

Share This Page