Is my well pump now dead?
#1
11-29-19, 09:36 PM
Is my well pump now dead?
About 8 years ago, my 120 volt well motor died. The well repair guy pulled the pump and replaced it with a 240 volt single phase. I installed a new breaker and we wired it with two 120 volt legs and a ground wire. There is only a pressure switch in the house. No control panel and no capacitor that I have seen. Are they possibly in the concrete top section that is at the top of the well?
Today, I temporarily removed the electrical junction box cover to use elsewhere and planned to replace it tomorrow. I later discovered the pump wasn't running when water was used. I checked the junction box and when I touched the wire nut for the black wire it arced inside a couple of times and the pump kicked on for a second when it did that about three times in a row very quickly. It was the outtermost wire nut connection and the cover must have been pressing on it previously and keeping it connected. I turned the breaker off, cut back the wires and redid the connection and replaced the wire nut. Now the pump won't start at all. I checked the pressure switch and the contacts are closed. I checked for power on both legs and I have 120 volts both going into the pressure switch and at the connection going out to the pump. I disconnected the wires to the pump and ohm checked both legs to the ground wire. The white wire has .47 M ohms and the black wire shows infinite. Is the pump motor shot now from the arcing connection I had?
Today, I temporarily removed the electrical junction box cover to use elsewhere and planned to replace it tomorrow. I later discovered the pump wasn't running when water was used. I checked the junction box and when I touched the wire nut for the black wire it arced inside a couple of times and the pump kicked on for a second when it did that about three times in a row very quickly. It was the outtermost wire nut connection and the cover must have been pressing on it previously and keeping it connected. I turned the breaker off, cut back the wires and redid the connection and replaced the wire nut. Now the pump won't start at all. I checked the pressure switch and the contacts are closed. I checked for power on both legs and I have 120 volts both going into the pressure switch and at the connection going out to the pump. I disconnected the wires to the pump and ohm checked both legs to the ground wire. The white wire has .47 M ohms and the black wire shows infinite. Is the pump motor shot now from the arcing connection I had?
Last edited by Fastwing1; 11-29-19 at 09:56 PM.
#2
11-29-19, 10:32 PM
In my experience, a loose connection shouldn't fry the windings in a motor, BUT it may mess with the circuit board. However, you might have triggered the lightning/overheat protection circuit in the pump, so I'd try the measurements again in a hour.
Fastwing1
voted this post useful.
#3
11-30-19, 05:22 AM
Member
I can't help you on whether you hurt your pump or not but most pumps don't run when water is used. Most households have a pressure tank. The pump fills up the pressure tank and then the water in the pressure tank is pushed through the house when a tap is turned on etc. Only when the pressure tank gets to a certain low level, which corresponds to a lower level of water pressure, the pump turns on again and refills it.
The pressure tank is there so the pump does not need to turn on every time someone needs perhaps only a cup of water. That turning on and off is hard on a pump so water systems are designed this way.
The pressure tank is there so the pump does not need to turn on every time someone needs perhaps only a cup of water. That turning on and off is hard on a pump so water systems are designed this way.
#4
11-30-19, 05:34 AM
Thanks, I did use enough water to engage the pressure switch, I tried to take a shower. Pressure is now down to 25psi.
#5
11-30-19, 05:43 AM
Hal_S
I left the circuit breaker off over night in hopes of some like you mentioned but things are the same this morning. Thanks for the suggestion of the lightning/overheat protection circuit in the pump. After coffee I'll try a few other tests before calling a professional.
I left the circuit breaker off over night in hopes of some like you mentioned but things are the same this morning. Thanks for the suggestion of the lightning/overheat protection circuit in the pump. After coffee I'll try a few other tests before calling a professional.
#6
11-30-19, 07:56 AM
Good luck - I'm dealing with an out of commission pump myself -
Two more cheap/simple things you can check
First thing to check (with power off) would be the infinite resistance on the black wire, e.g. is the wire broken or disconnected at the top of the well?
I would pull the well cap and check the connections/wire nuts at the top of well head.
A well-pump comes with it's own wires, those are connected with wire nuts/silicone crimps to the house wires at the top of the well casing. The pump impeller is basically a fan, so when you turn it on the pump impeller it will twist in the well, over time that can work the wire nut connections loose. If they're a simple wire nut, I'd undo-clean and then redo the wire nut. - but before finishing ..
Before checking the wire nuts at the pump, I'd disconnect the black and white wires TO the well at the pressure switch, just wire them together. THEN when you're at the well checking the wire nuts, check the resistance across both wires- if the black is actually broken, you'll get no continuity and an infinite resistance. If the black and white are fine, you'll get continuity and some resistance. If the wires are corroded, you'll get a reading somewhere in between.
Two more cheap/simple things you can check
First thing to check (with power off) would be the infinite resistance on the black wire, e.g. is the wire broken or disconnected at the top of the well?
I would pull the well cap and check the connections/wire nuts at the top of well head.
A well-pump comes with it's own wires, those are connected with wire nuts/silicone crimps to the house wires at the top of the well casing. The pump impeller is basically a fan, so when you turn it on the pump impeller it will twist in the well, over time that can work the wire nut connections loose. If they're a simple wire nut, I'd undo-clean and then redo the wire nut. - but before finishing ..
Before checking the wire nuts at the pump, I'd disconnect the black and white wires TO the well at the pressure switch, just wire them together. THEN when you're at the well checking the wire nuts, check the resistance across both wires- if the black is actually broken, you'll get no continuity and an infinite resistance. If the black and white are fine, you'll get continuity and some resistance. If the wires are corroded, you'll get a reading somewhere in between.
Fastwing1
voted this post useful.
#7
12-03-19, 02:57 PM
Hal_S
I checked for resistance across the disconnected black and white wires at the pressure switch. I had an open circuit. I checked them at the well head and found a loose connection on the black wire at the wire nut. I repaired the connection and retested the wires at the pressure switch. 4 ohms of resistance through the pump windings. Reconnected the wires to the switch and turned power back on, pump started running. I reassembled everything and recovered my well head. It's an old house and the well head is buried three feet deep in a cement casing with a cement cover. Not a fun job in MN when it snowing / sleeting outside while you're digging.
Thanks for your help sir!! Good luck with yours.
I checked for resistance across the disconnected black and white wires at the pressure switch. I had an open circuit. I checked them at the well head and found a loose connection on the black wire at the wire nut. I repaired the connection and retested the wires at the pressure switch. 4 ohms of resistance through the pump windings. Reconnected the wires to the switch and turned power back on, pump started running. I reassembled everything and recovered my well head. It's an old house and the well head is buried three feet deep in a cement casing with a cement cover. Not a fun job in MN when it snowing / sleeting outside while you're digging.
Thanks for your help sir!! Good luck with yours.
#8
12-03-19, 09:21 PM
Group Moderator
Good you got it working.
Just a FYI...... when working on a 240v device.... like a pump...... confirm that you actually have 240v. It is not enough to measure each leg to ground and see 120v because if one leg of the 240v is open (like it was in your case) you'll see 120v on both legs. That 120v comes in on the working leg...... goes thru the motor..... and then you see it on the other leg.
Just a FYI...... when working on a 240v device.... like a pump...... confirm that you actually have 240v. It is not enough to measure each leg to ground and see 120v because if one leg of the 240v is open (like it was in your case) you'll see 120v on both legs. That 120v comes in on the working leg...... goes thru the motor..... and then you see it on the other leg.
