Well pump pressure tank question

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hog island

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I replaced the entire jet pump system with a submersible 1/2 hp 120 volt pump, new pressure tank and Tee. The pump runs and shuts off with power still on the pump side of the switch. Thinking i may have left the dust cap in the pressure tank i pulled it out and I can see what i assume is the bladder. It's tight enough that i would think it would prevent the tank from filling. All air pressure is out of the tank. I can touch the obstruction but i have no idea what it is. Brand new tank.
Not a great photo but this is the best i can do. Appreciate any input.
 

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Looks like the bottom of the rubber diaphragm to me. Can't push it up until you get 39 PSI from the pump as the tank probably has 38 PSI air charge as as needed with a 40/60 switch.
 
Looks like the bottom of the rubber diaphragm to me. Can't push it up until you get 39 PSI from the pump as the tank probably has 38 PSI air charge as as needed with a 40/60 switch.
after some more research i'm leaning toward a faulty pump. I'll do a pressure check on the pump without the tank and see what I get. Also, i did confirm that the tank is a diaphragm type so for now the tank is not suspect.
 
Which 1/2HP pump did you get? Many of those cheap ones on the Internet will be 20-30 GPM models that won't build enough pressure to push the diaphragm up or work with a pressure switch. You will need a 10GPM or less version of a 1/2HP to work with a pressure switch.
 
Which 1/2HP pump did you get? Many of those cheap ones on the Internet will be 20-30 GPM models that won't build enough pressure to push the diaphragm up or work with a pressure switch. You will need a 10GPM or less version of a 1/2HP to work with a pressure switch.
after talking with the plumber we decided to pull the pump, max out the piping diameters to 1 1/4" to the tee, add a check valve at the pump and give it another shot. I will do the pressure test on the pump for S & G's. Lowes pump specs 9.5 GPH @ 60PSI for the depth we set it at. Fortunately the well is optional and utilized as a backup water source and for topping off the fish pond. County water was installed last year but my brother inlaw wants well water to the house now. My home pump is a 240 submersible thirty feet deeper and the yard hydrants have awesome output. This thing was less than impressive when we first powered it up let alone never filling the tank. I appreciate all the responses.
 
after talking with the plumber we decided to pull the pump, max out the piping diameters to 1 1/4" to the tee, add a check valve at the pump and give it another shot. I will do the pressure test on the pump for S & G's. Lowes pump specs 9.5 GPH @ 60PSI for the depth we set it at. Fortunately the well is optional and utilized as a backup water source and for topping off the fish pond. County water was installed last year but my brother inlaw wants well water to the house now. My home pump is a 240 submersible thirty feet deeper and the yard hydrants have awesome output. This thing was less than impressive when we first powered it up let alone never filling the tank. I appreciate all the responses.

I hope 9.5 gph is not correct. Again, what is the model of the pump? 115V or 220V won't make any difference.
 

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That pump will build 275' of head or 119 PSI. Shouldn't have any problem working with the tank and a 40/60 switch. 1" pipe is plenty. I would check the amps and voltage. A 115V motor works fine on 115V. But it should draw about 10 amps if it is pumping 12 GPM. If the voltage isn't right the amps and flow won't be either.

zoellerturbine_11gpm_pumpcurve.jpg
 
That pump will build 275' of head or 119 PSI. Shouldn't have any problem working with the tank and a 40/60 switch. 1" pipe is plenty. I would check the amps and voltage. A 115V motor works fine on 115V. But it should draw about 10 amps if it is pumping 12 GPM. If the voltage isn't right the amps and flow won't be either.

View attachment 48345
We have 121.7 volts at the switch on 12 AWG UF
 
OK good. Now if it is drawing 10 amps you have a big leak somewhere. Is it possible the valve to the county is open? If it is drawing 5 amps or so the pump is either restricted, out of water, or something is wrong with it.
nah, there is valve #1 to the house from the well enclosure and valve #2 from the pump to valve # 1 and both are closed. overkill but acts as a failsafe.
 
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