Low water pressure - Maintains 20psi

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Clueless89

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Hey everyone. I'll make this story as short as possible.

For a week we have had low water pressure. I've ignored it due to being busy running a business. I finally looked into it yesterday. Here's what my testing has showed me so far;

-water pump off, main valve off, no pressure drop
- water pump off, main valve on, water leaked pressure fairly fast
*I turned toilet water off as I had no visible leaks
- Again, water pump off, main valve on, no pressure drop this time
- Went to recharge pressure tank, bypassed filter, left laundry sink drain water out, main valve open, checked pressure again on tank and it was still the same. how can this be?
- Left pressure tank at recommended 28psi for my 30/50 set up.

WITH WATER PUMP OFF, TURNING ON ANY FAUCET WILL DRAIN ALL PRESSURE IN SYSTEM WITHIN 2/3 SECONDS

After all of this information that I've gathered, it seems as though the water pump is the only thing keeping water in my house, without it, the tank has no supply.

My questions;

Shouldn't the pressure tank be drained to 0 psi when pump off and letting water run dry to faucet?

Would my situation be a bad pressure tank or is the pump just not able to supply enough water to the tank?

Thanks in advance!

Adam
 
After all of this information that I've gathered, it seems as though the water pump is the only thing keeping water in my house, without it, the tank has no supply.

EXACTLY! Water comes from the pump, not the tank. All a pressure tank is for is to reduce the number of on/off pump cycles while using water.

There should be 28 PSI air charge in the tank before the pump is even turned on. The 28 PSI air charge should stay in the tank just like a spare tire has air in it before you put it on the ground.

If it is a jet pump you probably have a clogged venturi nozzle or a suction leak. If it is a submersible you probably have a hole in the pipe or a worn out pump.
 
COuld it still be a leak in a pipe if it holds pressure while pump off?
 
No water pressure leaks when pump is off and main valve to our house is closed. When main valve to our house is open, pump off, we do lose pressure. Turned out our toilet was leaking slightly.

Would this mean it's the pressure tank or pump? I've still been messing with it but I can't get the pressure to go over 20 psi.

If water pressure is at 0 psi and I turn the pump on it jumps instantaneously to 20psi and stays there.
 
The tank has NOTHING TO DO with pressure. If you only get 20 PSI it is because the pump can only build 20 PSI or there is a major leak, which you seem to have eliminated.

Jet pump or submersible????
 
Went out to look at the pipe outside and this blue pipe in the picture was not lined up and disonnected from this cap. Would this cause any pressure loss from the pump?

IMG_3515.jpg
 
No, that is the wire conduit for your submersible pump.

Does the pump ever satisfy the pressure switch? Or is it always calling for water? The switch should be satisfied with around 50 psi. The gauge my say 20lbs, but they are a cheap and unreliable gauge most of the time. When diagnosing a problem, I usually swap in a new one
 
No the pump will never satisfy the switch and it runs continuously. I've heard of the switches going bad or the pipes to the switch or gauge being clogged but I believe it's accurate simply because our water pressure in the shower and upstairs sinks are really lacking pressure. The only sink that doesn't seem affected is the basement sink.

If the gauge is reading inaccurately however, could I just checked the air pressure in the pressure tank to get an accurate water pressure reading? As the water pressure builds against the air pressure in the tank, the air pressure should also rise, correct?
 
If the gauge is reading inaccurately however, could I just checked the air pressure in the pressure tank to get an accurate water pressure reading? As the water pressure builds against the air pressure in the tank, the air pressure should also rise, correct?
Yes, that would tell you the pressure in the system provided your air gauge is accurate.

You should know that a pump running continuously while no water is flowing in the system will burn up in a very short period of time. First the impellers which are almost always plastic melt. Then as the heat continues to build, the motor finally dies. It would only take one or two melted impellers to drop your pressure to 20 psi or so.
 

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