New homeowner - well not working

[Mandinca]

I am new to my home that has city water as well as a non-working well pump. I would like to revive the well to use for irrigation so I started troubleshooting.
It's supplied by 230V on a dedicated double breaker at my main panel. That feeds an isolation switch which then feeds the pressure switch then to the control box and then to the submersible pump.

The control box says it's for a 230V 1/2 HP pump so without pulling the pump I have to assume that it's a 1/2 HP pump.

The pump itself has four wires coming from it to the well-head.
They are yellow, red, black and green.
The yellow, red and black are spliced into the wires going to the control but the green has been cut and taped off. There is no green to the control box.

So far I have established that, since there is no pressure at all in the tank, that the pressure switch is "on" - I have confirmed this by measuring 230V at the control box. The control box had a broken-looking capacitor in it so I have replaced that, like for like.

Since I have limited electrical knowledge I just used a voltage "sniffer" on the wires on the pump side of the splices in the top of the well shaft that I mentioned earlier - voltage is detected when everything is "on".

Is it safe to me assume that everything up until the pump is working correctly and that the pump is what failed, or maybe the 3 wire from the splices to the pump ?

According to the town municipal offices the city water was connected to the home about 6 years ago, presumably because the well failed somehow.

One other test I performed was to hang an amp tester (clamp type) around the three wires running from the control box to the well and when we turned on the isolation switch the current measured exactly 0.00 - it didn't even blink. When we ran that test we didn't know that maybe the numbers cancel each other out and that we should have tested each conductor separately. I no longer have that amp tester as it was borrowed.

So.....
Is there anything else I can do to make a final determination before I pull the pump. I measured the well depth and stopped plumbing when I ran out of line at 250 feet....presumably the pump won't be at the bottom but it could be down 250 feet. Maybe more. My well shaft water level is about 15 feet below grade so hopefully the plumb bob just slid by the well pump about 100 feet down....I'm not usually that lucky :-(

Any advice you can give me would be very much appreciated.

 

[Valveman]

Voltage going down the well but no amperage means the wires are not touching the motor. You can double check with an ohm meter. There is probably no continuity between the wires going down the well?

 

[Sponsor]

 

[Mandinca]

OK thanks. So to test continuity do I have to isolate the red yellow and black from the control box to be certain I'm testing continuity of the pump (not the box).
I read that red to yellow will be one resistance range and black to yellow will be another. I had already tested it with everything still connected and also with the "probably bad" capacitor, my readings were R-Y 18 ohms and B-Y 6.5 ohms.
Maybe I'm looking at the wrong table and in any event, I'm assuming this is a 1/2 HP based on what the control box is for. It could be anything in the well.

 

[Reach4]

Is there anything else I can do to make a final determination before I pull the pump.

https://terrylove.com/forums/index.php?threads/white-paper-measuring-3-wire-pump-resistances-with-unknowns.67706/#post-503161 #7 may be of interest if you can measure resistances accurately.

 

[Mandinca]

The depth of the pump isn't really a deciding factor, I just don't want to pull it unless I already know there is definitely an issue with either the pump or the wire supplying it. (rather not go to all that trouble to find out that my relay was bad, or something like that)
With all of the information I have gathered so far can you tell me with any certainty that my problem is either the pump or the wire supplying it ?
With my voltage sniffer detecting voltage on the pump side of the splices (at the top of the well shaft) can I assume that the splices are good and therefore if it's the wire itself then the issue is further down the well ?

Reach4, thanks. I think that's a bit above my pay grade.....I know my way around a meter but I'm not sure I follow the process.

 

[Reach4]

I know my way around a meter but I'm not sure I follow the process.

Measure and post the three resistances that you measure.

 

[Mandinca]

Do I disconnect the three wires from the control box first ?
And....do I measure them at the box end or where they are spliced at the top of the well shaft ? Does it matter ?

 

[Reach4]

Do I disconnect the three wires from the control box first ?

Yes.

And....do I measure them at the box end or where they are spliced at the top of the well shaft ? Does it matter ?

Box end is less work and does not interfere with the insulation of the splices.

 

[Mandinca]

Great, thanks. I'll probably do this in the morning and post my results tomorrow.

 

[Mandinca]

OK, so I had a few minutes - I'm using a Fluke 87 III and disconnected all three wires from the box before testing.

R-Y 18.7 Ohms
R-B 23.3 Ohms
Y-B 6.7 Ohms

Below the Ohms indicator my display reads 400 and I don't know what that reading is for. Nowhere does it say K so I'm assuming the test results are Ohms, not kilo-ohms and that 400 indicator is for something else. When I'm not actually testing anything the display reads 40 instead of 400. Can't see anything in the online manual that describes what it means.

 

[LLigetfa]

One other test I performed was to hang an amp tester (clamp type) around the three wires running from the control box to the well

Pretty sure you need to do each wire individually, not all three at once.

 

[Reach4]

OK, so I had a few minutes - I'm using a Fluke 87 III and disconnected all three wires from the box before testing.

R-Y 18.7 Ohms
R-B 23.3 Ohms
Y-B 6.7 Ohms

Below the Ohms indicator my display reads 400 and I don't know what that reading is for. Nowhere does it say K so I'm assuming the test results are Ohms, not kilo-ohms and that 400 indicator is for something else. When I'm not actually testing anything the display reads 40 instead of 400. Can't see anything in the online manual that describes what it means.

Based on calculations of your measurements:
Rstart=16.6 ohms
Rrun=4.6 ohms
Rw=1.05 ohms for each wire.
Looking at the wire gauges, you could estimate the wire length across+down

For a 230 volt 3-wire pump from Franklin AIM manual, expect
Rstart=16.7 to 20.5 ohms
Rrun=4.2 to 5.2 ohms

So the resistance measurements don't show a problem.

 

[Valveman]

I agree those resistance numbers look fine. You also need to check between each wire and ground, where you should get no continuity. A "sniffer" isn't good enough. You need to make sure you are getting all 230 volts to the pump.

 

[Mandinca]

To check each wire to ground, make sure power is off and disconnect from the box again presumably ?
Since there is no actual ground in the box what do you suggest I use as a ground ?
Basic electrical question, I know

 

[Valveman]

Yes take the wires out of the control box. Any earth ground will work. Steel casing or steel pipe you can use as a ground. Or just drop one probe in some muddy earth.

 

[Reach4]

To check each wire to ground, make sure power is off and disconnect from the box again presumably ?
Since there is no actual ground in the box what do you suggest I use as a ground ?

You are wanting the resistance to ground from a pump wire, other than green/bare, to be at least 100,000 ohms. No need to measure vs every wire, since you know there is a low resistance path among the three power wires.

You should be able to use the green/bare wire as a ground for the measurement, although there could be something in your house that makes that not work so well.

A control box has more that can go wrong besides the start capacitor.

 

[Bannerman]

Since there is no actual ground in the box

Is the electrical feed to the control box installed within metallic conduit or a metal pipe? Is the box itself metal?

Metal electrical conduit is often used as a ground conductor so you may wish to also check continuity between the metal box and an alternate ground connection to determine if the box is actually grounded. If so, the green grounding wire from the pump that is currently cut-off, should then be connected directly to the box.

 

[Mandinca]

I used the city water main where it enters the house - 1" copper.

R-ground 2.04 M Ohm
Y-ground 2.17 M Ohm
B-ground 3.51 M Ohm

None of them read "OL" ?

 

[Mandinca]

Probably easier if I post a picture.

 

[Reach4]

I used the city water main where it enters the house - 1" copper.

R-ground 2.04 M Ohm
Y-ground 2.17 M Ohm
B-ground 3.51 M Ohm

None of them read "OL" ?

Plenty of margin. The AIM manual Table 47 calls for greater than 500,000 ohms for a used pump wired into place. They call for a megger (high voltage ohmmeter). Their spec is more stringent than my 100,000 number.

Anyway, your insulation is in good shape.

Next you could check the currents 1 and 5 seconds after you turn on the power. Then turn off the power with that handy switch as you think about the results.