I have a house that has it's own well, the pump is 200 feet deep submersible that connects to a Wellmate WM-6 pressure tank.

I have had this house for 5 years but I think the pressure tank is original to the house which was built in 1998.

Lately when we turn on the water, we get good pressure for a few seconds and then it bleeds down to a trickle.

I replaced the pressure switch last year with a 40/60 and checked the air pressure in the tank (empty of water)

at 38 psi. I just rechecked the tank pressure today at 38 psi and bled the water filter to remove any air in that

but the problem persists.

Our hose outside used to give good pressure but now only goes a few feet and bleeds

down to almost nothing.

I did watch the pump cycle with open facets it turns on at 40 psi and shuts of at 70 psi (I did adjust the switch for higher

pressure). So I believe that the pump is fine but there is a problem with the pressure tank however, it's holding pressure

and no water comes out of the air valve.

There are no water leaks as far as I can see in the crawl space where the tank is but the main line from the pump is underground

and I cannot see that.

There is no sediment at all in the water from any water tap, it's very clear with no smell or foul taste.

I'm sure it's the tank itself that is the problem but if anyone here has any idea's I sure would like to hear them.

Thanks!

Dumb question but, are you positive it's not the filter? A full filter can act like that. I'm no well guy but have had one for years and aside from my military years, always lived with one. A bad tank usually gives you water in the Schrader valve if the bladder is blown. There's very little else that can go bad besides the tank itself rusting out.

What you're describing sounds like something obstructing flow upstream... full filter, partially closed valve, corroded pipe, sediment. That's my thought.

I think you may be right. I just changed the filter last month but the one before that

crumbled in my hands as I replaced it. I think they may be bogus knock offs.

They are a name brand I bought on Amazon too.

The problem did start a few weeks after I put the new filter in so I'm going to go buy

a known real filter from Lowes and replace it.

The strange thing is, the pressure tank seems to be operating fine. It passed all the tests

but still gives low pressure so maybe it IS the filter.

EDIT: I'm going to check the reviews for that filter on Amazon and see if this is a problem for others.

EDIT #2: I just read most of the reviews for this filter. Most of them are very good reviews but

there were a few describing exactly what I am experiencing with our water pressure. So yeah,

I'm changing the filter tomorrow and see what happens.

Thanks!

Agree with Homesteader, flow restriction somewhere.

Last time I had this problem, it was a clogged valve just after the pressure tank.

Take cover off pressure switch, watch the contacts.  Turn faucets on, does the pump run constantly?  If so, bad pump.  If it cycles on and off, restriction in the line.

The pump only runs when the pressure drops to 40 psi shuts off at 70 psi and stops.

The pressure holds until there is a demand for water (tap turns on).

It cycles normally. I installed the switch and a new gauge last year.

I did see and hear the switch operate, totally normal.

Thanks!

If you have an iron filter or softener in your system the resin bed in either one could be fouled.
That has been the culprit for me in the past.
Not terribly complex to remedy on your own.

So good flow and pressure to the tank?  Low pressure and flow after?  Did you observe the contacts while you had faucets open?

There is a filter (5 micron AO smith) and there is a water softener installed and seems to be operating

normally. I keep adding salt every 3 months or so as needed.

Whoever installed this system could have done better.

There is no "T" on the pressure tank, no relief valve, no drain, no check valve

and it's a 20 gallon fiberglass tank, a little small for the house. Also the outside tap

is not unfiltered, it's in the system. I might have to redo the whole works and add

a larger pressure tank but I'm limited to the opening to get into the crawl space.

As others have stated the filter may be the problem, I'm changing that today with a

20 micron filter from Lowes and we'll see what happens. The piping for the system is

Schedule 40 PVC but connects to copper for the entire house after the filter. The multiple

valves in the system are also PVC and one in particular is sticky? Tough to turn.

Thanks!

Yes good flow to the tank and yes I observed the switch open and close in operation.

I'm on my way to Lowes now to get new filters (20 and 40 micron) the 5 micron installed may be too fine.

I plan on changing the tank as well next month. The existing tank is a Wellmate 20 gal. fiberglass tank

and honestly it's a little small for our needs, so I'm going to get a 30+ gal tank WITH a "T" and install all of the

components needed that are not present in my current system (Drain, relief valve, etc.) But for now

I just want the pressure back.

Thanks!

In my professional opinion, the filter is the most likely cause of the issue. When filters become clogged, they initially allow for a good flow of water, but this flow rapidly decreases over time. If there is a significant delay in the pump turning on, this also suggests a restriction in the system. Furthermore, if the flow of water is halved when a second fixture is turned on while one is already running, this further indicates a restriction or filter issue.

There are not a lot of systems that can run on a 5 micron filter. There are one million microns in a meter. A human hair is approximately a hundred microns wide. 1 micron is the same as . 00003937 inches, or 0.001 mm. 25 micron is what I carry in my service truck.

Thanks for the response and diagnosis. I just returned home with a 25 micron filter

and new O ring, they didn't have any 40 micron filters. I'll get that installed and report back.

I may have to replace all of the PVC pipes and valves next month when I upgrade the tank.

Would you recommend a check valve along with the drain and relief valve. I've seen videos

where one would use a check valve and the other would not because of a possible vacuum.

Thanks!

Well everyone, I changed the filter and we now have good pressure restored to the house.

The filter in question was branded as an AO Smith 5 micron carbon bought off Amazon.

It disintegrated in my hands just as the last one did and there appeared to be no carbon

left on the paper.

When we turned the tap back on in the kitchen, a huge plume of carbon collected in the sink.

I have no idea if that was a bogus filter or not but I replaced it with a generic 25 micron mesh

type filter from Lowes and we have the water pressure back.

Thank you all very much for all of your help, my wife is ecstatic over this and now we can do laundry!

Thanks again, Paul and Rose.

Nice!

I'm glad you've fixed it.

Water pressure is something that you don't think about until you don't have it.

Oh, and thanks for the micron lesson.

regarding filters, micron rating and flow ratings are huge.
I use 5 micron filters, it has a flow rating of 8gpm. I forget what my housing does.

I replaced my old housing that had a built in shutoff. I forget the specs, but that housing vs a housing without a built in shutoff, had gallons more flow capacity.

I use the ap110 filters, they are 5 micron. 25 micron filters less and flow more.

during my flow issues, I finally found the culprit, it was a ball valve not opening fully even when the handle was straight. I cut it out and the valve was 1/2 closed. ball was stripped where the handle attaches.  I soldered in all new valves at that location and added a bypass as well..
I found it by adding a pressure gauge on my hose faucet outside. ran 2 sinks, and was asking my wife what the pressure was outside vs what I saw at the tank.

Well done!  Nothing like solving a problem with your own two hands.  Tim Taylor Tool Time grunt!