Pressure seems to be stuck

[jaklim]

I have a 1/2hp jet pump in my basement with a Pressure Tank. Both are approx. 5 years old.
Pressure on gauge is pinned at 20psi. When anyone in the house flushes a toilet or runs the sink for more than a minute or two, the pump goes on, then shuts off - almost as if the get the pressure right back to where it was just a minute ago - 20psi according to the gauge.

The switch seems to be a 20/40 switch.
Take pressure in the bladder tank is just over 30.

I pulled the line from the pump to the switch to see if something was in there. Couldn't really tell.
We do have rust and sediment, but don't know if something is just set wrong or clogged.

Any and all advice would be greatly appreciated.

Jk

 

[Rancher]

When anyone in the house flushes a toilet or runs the sink for more than a minute or two, the pump goes on, then shuts off - almost as if the get the pressure right back to where it was just a minute ago - 20psi according to the gauge.

Does the gauge move when the toilet is flushed, if not you need a new gauge, and probably the tubing cleaned out.

The switch seems to be a 20/40 switch.
Take pressure in the bladder tank is just over 30.

You didn't say how you took this measurement, if you didn't empty the pressure tank you measured the water pressure, not the air pressure in the tank.

Turn off the pump, drain the tank, measure the pressure in the tank, should be at 18 psi.

Rancher

 

[Sponsor]

 

[jaklim]

measurements

Here's how I got the measurement.
The 30 psi on the tank was air pressure taken from the top schrader valve.
The 20 was on a pressure gauge just outside the tank on the pipe after the pump.
The one thing I noticed after pulling the cover off the pressure switch is that there is no short adjust valve. Just the long center adjust. It is a pumptrol brand with a small hose underneath that runs to the cast iron casing on the jet pump.

 

[Wondering]

You have too much air in the tank if you have 30 lbs and are running a 20/40 switch. You need to drain the tank,let the air out to 18psi then start the pump back. While you are doing this you should go ahead and put on a new gauge also. Then you can tell exactly what you have.

 

[Speedbump]

I think the air measurement was taken with system pressure still intact. The pump must be turned off, all the water pressure let off the system, then you can check the air.

I believe you will find out your tank is waterlogged, and your gauge is bad.

bob...

 

[jaklim]

checking the system

On the top of the take which is only 5 or so years old, there's a small sticker that says tank Factory charged with 28psig (air). I remember trying to pump some more air in the tank a couple years back which could account for the 30psi read (air).
I will try to drain the system and reread the air pressure in the tank. Then replace the pressure gauge that's on the pipes. I read that air pressure should be 2 lbs below that of the low end of the pressure switch would account for the previous post that said put it to 18psi.
My question is twofold. Can a pressure tank fail in just 5 years (assume so because anything is possible. But wouldn't there be other signs of it's failure?

Also, could the discrepancy between the air pressure in the tank (factory shipped with 28 and not changed since) and the pressure switch 20/40 be part of the problem.

Wondering also if I should just replace the inexpensive pressure switch too - much cheaper than a pressure tank and all it's hassles.

jk

 

[Rancher]

On the top of the take which is only 5 or so years old, there's a small sticker that says tank Factory charged with 28psig (air). I remember trying to pump some more air in the tank a couple years back which could account for the 30psi read (air).

Nope, if you didn't drain the tank of water before reading that 30 psi, then what you measured was water pressure.

My question is twofold. Can a pressure tank fail in just 5 years (assume so because anything is possible. But wouldn't there be other signs of it's failure?

Yes a tank can fail in 5 years, the average life is 7 years, which means some fail at 5 and some fail at 9 years.

Also, could the discrepancy between the air pressure in the tank (factory shipped with 28 and not changed since) and the pressure switch 20/40 be part of the problem.

The pressure switch could have been adjusted to be a 30/50 switch, you need to drain the tank and measure the pressure in the bladder before asking for more advice.

Wondering also if I should just replace the inexpensive pressure switch too - much cheaper than a pressure tank and all it's hassles.

Replacing a cheaper pressure switch won't help if your tank is waterlogged, however you may need to replace the switch anyway if your tank is waterlogged and the pump has been cycling a lot. The contacts may be destroyed.


Rancher

 

[Speedbump]

Yes tanks can go in less than 5 years. In fact many do. There is a hugh difference between quality and price when it comes to Bladder Tanks.

Your correct on the two lb less thing.

Pressure switches either work or they don't. If it's turning on/off the pump, it's working. No need to change it.

If your pump is turning on and off more than it used to (in other words with less water usage) you can assume the tank has not enough air in it. It could be that it has too much air, but the problem would have occurred when you added the air a couple of years ago.

bob...

 

[jaklim]

Update - on pressure - gauge etc.

Here's the latest.
I drained the tank. Checked the pressure (air) it was low - 14psi. So I put it back up to 18psi as I have a 20/40 switch. Put a new pressure gauge on the system - old one seemed to be stuck. May try to test to prove. But put a new one on.
Pump now goes on at around 20psi and then shuts off at 35psi.
Wondering (or should I really care) if it goes off at 35 vs 40.
There is only one adjust nut on the pressure switch - set to 20 (on) and would assume (off) at a 20lb differential (40 or so)

So I will see if I get the quick on now the moment one toilet is flushed - I'm assuming no. That I will have more time before cycle.
So should I care about the 35 - Or should I chance the switch to a 30-50. Will this give me a bit more pressure?

With these answers I will humbly end this thread with many thanks to all who contributed.

 

[Speedbump]

I don't know what kind of switch you bought (sounds like big box to me) but all switches are supposed to have at least a 20 lb differential. With only one adjustment screw, you can't change that. You can raise the pressures though instead of buying another switch. Just turn the screw clockwise in most cases to raise the pressure.

bob...

 

[Wondering]

Just remember if you change your cut on pressure you will need to adjust the air charge in the tank. If you go to 30psi cut in then you will need to adjust to 28psi of air in the tank.

 

[jaklim]

Thanks for this and all prior advice. As of now the pump is not cycling on as much as it used to and the pressure seems to be pretty good. I my try to send the pressure up a bit down the road but for not it's working better than it did.
Thanks again - very helpful forum