I know this topic has been covered but it seems my situation is unique so any help would be appreciated. The issue is simple, the pressure tank only partially fills, maybe a gallon or two, I can move the tank with my pinky finger, but here's the thing....if I turn the pump off and turn the water off and then drain the tank it will fill up properly when I turn everything back on again, but once the level goes down during it's first use it will only partially fill after that. The tank is a bladder type and about 2 years old, the pump is set at 30/50 and cuts in and out at those settings, I've removed the house filter to eliminate a filter problem, the tank pressure when empty is at 28psi, there is no real problem with water pressure although it does vary while showering, the pump is not short cycling. Any ideas why the tank won't fill??
Tank patially fills
- Thread starter greenbay1
- Start date
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What size is the tank?
Bladder tanks are not supposed to fill to the top. They typically only fill about 30%. The rest is air pressure. It's the air that makes them work. Water won't compress, air will. So air is the spring that pushes the water out of the tank.
From what you have described (other than the "but here's the thing....if I turn the pump off and turn the water off and then drain the tank it will fill up properly when I turn everything back on again, but once the level goes down during it's first use it will only partially fill after that." part) your system is working properly.
From what you have described (other than the "but here's the thing....if I turn the pump off and turn the water off and then drain the tank it will fill up properly when I turn everything back on again, but once the level goes down during it's first use it will only partially fill after that." part) your system is working properly.
I agree, the system seems to be working but why won't the tank fill? When I drain the tank as described and then restart the pump and water flow it fills to about 50% but once the level goes down due to use it will only fill to about 10% (if that) from then on. It would seem to me that a 50% fill should be correct?
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No.
Assuming you have a common 20 gallon tank with a 30/50 switch at 28 psi, you will only have a draw down of 6-7 gallons. The tank will remain fairly light. You are working with the capacity of a bladder, not the steel tank itself
Assuming you have a common 20 gallon tank with a 30/50 switch at 28 psi, you will only have a draw down of 6-7 gallons. The tank will remain fairly light. You are working with the capacity of a bladder, not the steel tank itself
Great answer!
I'm wondering what makes him think it's filling to 50% sometimes?
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Not sure. You know as well as i do that theres no visual way to determine the water level in the tank. It well vary depending on what PSI you are running, and the brand of tank as the shape of the bladder itself is not consistent with every make/model.
My short answer would be this. If your air bladder is good, the set up you have right now is normal
My short answer would be this. If your air bladder is good, the set up you have right now is normal
I fully agree except where he is saying the tank sometimes fills up to 50%. That doesn't make sense; and I'm wondering what he is doing to determine this.
Just estimating I presume
Yup, that makes sense.
Ok, since this season's Super Bowl champions are on a bye this week I decided to go out and find out for sure how much water. First I ran water till the pump kicked in and waited for it to shut off, I then turned off the pump and water and drained the tank and measured the water, just short of 3 gallons came out, I measured it. I then turned on the pump and water and waited till the pump quit and then went through the same process, this time I got about 7 gallons. I can repeat this until the cows come and it won't make any difference, under daily use it will only fill to 3 gallons, but it will fill to 7 gallons ONLY if I drain the system and start it up again, why is that? and which amount is correct for proper operation of the system? It's a 20 gallon tank BTW
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What do you mean you turned off the pump "AND WATER"? Then: "just short of 3 gallons came out, I measured it." Then: "I then turned on the pump AND WATER and waited till the pump quit and then went through the same process, this time I got about 7 gallons." I'm not sure what you mean by turning off the water then turning it on.
Without doing anything else; you should be able to run water from a cold faucet anywhere and wait until the pump goes on. Now turn off the faucet Then when the pump goes off, open the faucet, measure the water that comes out until the pump starts. Each time you do this, the amount of water will be the same. Something your doing in the process is changing your result, I'm just not sure what that is.
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Let me try this another way. Let's do a hypothetical and say that both my tank and pump failed at the same time, I go out and purchase a new water tank and pump and have them installed. I fire up the system, the pump kicks on, goes up to pressure, fills the tank with 7 gallons of water and then switches off. I then go outside and turn on a outside tap (or any tap) and let it run, the tank draws down, the pump kicks on but only fills the tank this time with 3 gallons and then shuts off. What would you say the issue is?
Incorrect air pressure in the tank.
To be perfectly honest, I have no idea. I don't know what your doing that your not telling us, but your obviously leaving some things out.
It's a 30/50 switch and tank is set to 28 psi
28psi empty or full?
