Low/fluctuating water pressure after power outage, pump issue??

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dmaves

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We lost power at our home a week ago for about an hour, the next morning we woke up to limited water pressure. We've had this problem before, but it was caused by scale/sediment, and it would fix itself. However, this time it did not fix itself, thus a different problem this time.
I thought at first it might have been a clogged inline filter for our culligan system, checked that and cleaned it; still no go.
After this, I thought maybe it was the pressure switch, however, I can get the pressure switch to trigger by moving the lever, however, the system can't build a high enough pressure on its own to trip it. The gauge next to the pressure tank will not read higher than 30-35psi, even in the morning before any water usage.
I tried cycling the breakers and power switches, and I could hear/feel the pump shutting on and off so it is working, I'm just not sure its running at full capacity, and thus the reason for low pressure??
Another odd thing is that sometime the pressure appears to be better (not 100%) for a short period of time, then it drops down to worthless piss stream again, excuse my language.

Does anyone have any input/advice on this issue??
 
Is your pump in the house or in the well? What kind of pressure tank do you have?

I had a similar problem once where my foot valve was letting water drain back over time. When the power was on if I lost some pressure to drain back it would replace it before it was a problem and I never noticed the loss. I had a shallow well with a jet pump at that time.
 
I would first get rid of the cartridge in the in line filter since it serves no purpose other than to make the seller more money.

If this is a jet pump, it could have a plugged jet. If it's a submersible pump, you could have a hole in the drop pipe or the pump could have gotten hot and melted an impeller or two.
 
I have a submersible pump (no pump in the house) and have a sealed diaphragm style pressure tank, one of the common blue type ones you typically see.

I find it odd that we started to witness the pressure issues after a power outage.
 
I agree, it's a little odd that it is acting up after a storm. The only kind of damage a storm can do to a submersible pump is lightning getting into the motor or controls. Since it's running and making some pressure, lightning didn't get it. If it continues to run for more than a minute chances are there is nothing electrically wrong. So it's either the pump or the pipe. You could have a leak anywhere from where the pipe leaves the house near the tank all the way down to the pump.
 
If something was clogged upstream you would still build pressure at the pump and or tank where your gage is. You would just have a flow restriction. Seeing as how your pump is in the well that rules out loosing prime etc. The pump is coming on and running just not making pressure. If you shut the out valve for the tank and manually run the pump bypassing the pressure switch and all you can get deadheading the pump is 35PSI the problem is down in the well. Pump not making pressure or pipe leaking at connector or pipe itself, or the line between the house and well. May have not had anything to do with the power outage.

You may be able to take the cover off the well and listen down the pipe to see if you hear a leak in there or if you have a pitless adapter look for a leak there.
 
Make sure you have 240 volts to the pump. Half power or 115 volts can make it act that way, and could have happened during a power outage.
 
All good advice thus far; so I can just pull the cover off my well and listen for a possible leak in the down pipe?

Also, I will have to see if I there's a valve before the pressure tank and see if I can build pressure. My original thought was a clog somewhere, but seeing how I am only building 35psi MAX, it makes me think there is a separate issue.

Pumpguy, how can I test for correct voltage to the pump?
 
If this pump is wired for 240 volt and you loose one leg, it won't run on 120 volts unless you have far greater problems.
 
It depends on how deep your well is and how big the casing is and how deep the connection is where the pump line connects. It’s just something I would try before I pulled it all up. As to checking voltage I’m no well pump expert but you can check voltage going out to make sure you have power going out of the house on the lines. That’s easy enough. I’m also thinking and the experts will chime in that if you disconnect it at the breaker you could compare resistance on both legs of the 220 and it could show an open leg.
 
Check the voltage at L1 and L2 either on the outlet side of the pressure switch or at the control box.
 
If this pump is wired for 240 volt and you loose one leg, it won't run on 120 volts unless you have far greater problems.

You would be surprised. I have had them working that way for years. They just won't build enough pressure to shut off.
 
My guess is that its going to be something electric given the timing of the issues and a power outage as we got quite a bit of flickering of power prior to it completely going out.
 
It's doubtful that a pump once set for 230 volts will run on 115 volts. Reason is, the other leg would have to go to ground to complete the circuit. I did have a Tait sub that the electrician wired for 115 volts. It was a 230 volt pump and the customer complained that it wouldn't run his sprinklers very well. We had the electrician go back and wire it correctly and it did a great job. It also made enough pressure to make it to 60 psi and shut off at 115 volts.
 
It also made enough pressure to make it to 60 psi and shut off at 115 volts.

A shallow well might make it to shut off pressure, but not a deep well. It maybe doubtful that a 240v pump will run on 115v, but it does happen.
 
It maybe doubtful that a 240v pump will run on 115v, but it does happen.
I agree, but one leg of the 230 volts would have to been burned in half and the side of the wire that goes to the pump would have to become grounded somehow, like against steel casing or in some very moist conductive soil to make a complete circuit to create the 115 volts to the motor. And like you said, it wouldn't make as much pressure as it could on 230 volts. We test motors all the time in our shop that are 230 volts with 115 volts. They fire right up. But if you put a load on them, they start to dislike it a lot.
 
You would be surprised. I have had them working that way for years. They just won't build enough pressure to shut off.
It would be wired incorrectly to run on 120 would not just happen.
If you loose one leg, you loose connection to make the loop back to the other breaker. It would have had to fry a connection and then make connection with ground and or nuetral if one is there. I guess that could happen , easy to prove by removing one leg and then the other to see if it will run on one leg.

I would be more suspect of the motor running outside it's voltage limits for some time, a stressed motor may not be able to take the shock of an interupted cycle, when the power went off.
 
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