Electricians...I have a mystery

So this will cause a 100 amp breaker to trip when it only looks like it's pulling 45?

I'm not smart in this area but it seems like a logical place to start.

Not if you only have 45AMPS running.

Fix the real problem, don't put a band aid on it and have to rewire a bunch of things to prevent a fire.

Breakers prevent fires.

Water heaters do not have or need a neutral conductor. As far as the his neutral between his service and the utility is concerned if he lost that, he would have a lot of stuff in his house let the smoke out.

Yeah...100 amps is plenty...or it used to be. We already started the plans for changing everything outside at the same time as the tank. It seems logical anyways to start at the pole and work our way inside the house.

Well, that's good to know. Definitely no smoke.

Call the electric company to check their connection at the meter. I had a friend who was having problems. Turned one of the incoming connections was bad.

Heck, it might just be the water heater element or elements.

We are taking the meter box off to change the wiring and everything so we will see if this is a possibility.

The wires coming into the box are older and we are also thinking it's possible that water could be getting into the casing.

Put a couple of voltmeters on the line at the panel between each leg and neutral. If the voltages don't remain the same on both legs regardless of load, the neutral may have a high impedence connection. As loads vary on the two legs, one side will go low and the other high. This can cause all kinds of problems including all appliances on one leg getting serious overvoltage. In the case of heating appliances, it will cause overcurrent on the high side. In the case of motors, it will cause overcurrent on the low side. This is a separate issue from the water heater since it doesn't use the neutral at all. Bonding the neutral to ground is not sufficient - it must have a good connection to the service neutral, and the service neutral must have a good connection to the centertap of the service transformer.

I was hoping that this was the problem. When we started looking at the outside box we just wanted to be sure everything was right...even if I'm spending money I don't need to.

I'd rather do it now and not in the brutal winter.

Is the water heater electric? Most likely. You have a bad element causing the problem. Install the new water heater and try it out.

It could be the main outside, but unlikely since it works if you turn off the water heater.

I really appreciate all of the responses. If I didn't get to respond to someone individually I will still be using your advice. I'm going to show this to my buddy when he comes to install the water heater. THAT we can do even when it's raining.

So, we should have an idea when we get the water heater installed if the main doesn't get hot. I'm still going to have him check everything that was discussed here.

I will keep checking back to get more ideas.

Thanks people of GLP. You guys helped me a lot. Many, many thanks to you.

Specifics, sure. You likely know better then I.

But in general, bad connections will create voltage drops and many appliances will draw more amps to compensate. OP is tripping breakers, too many amps.

Just tossing out ideas

Good luck, don't give up you'll figure it out!

Thanks! I love a good mystery. I just suck at electricity. I am hoping it turns out that it's the bad water heater...just for bragging rights...'cause I did figure that out myself.

Mon-Wed we fix everything so anyone who likes to hear the ending to an electrical mystery check back.

Check the gfci

That's the plan! Trying to do it right...for sure.

OP,
So your Main panel is outside and inside is a sub panel? If so, make sure the inside panel Neutrals are NOT tied to the Ground bar. The Ground bar should only have current flow on it if an appliance or component shorts to ground. Otherwise you are setting up a parallel path for the Neutral return current to flow back to Neutral.

Check if there is a green grounding bar or strap connecting the 2. If so remove the strap, bar or wire and separate the Neutral bus from the Ground bus. Per code the Ground bar should have a separate EGC (Equipment Grounding Conductor) tying it back into the Main panel ground bus bar.

Like someone mentioned earlier, make sure your Main panel Grounding bar/bus is secured to a grounding rod near the outdoor panel. If it is secured, not a bad idea to take the grounding conductor clamp off and clean up the clamp and the ground rod to make sure they are getting a solid bond.

Some older homes used Aluminum wiring. We had a well pump junction work loose on account of the aluminum wire corroding over decades.

It shorted out everything intermittently. Took years to find in the crawl space. It could have burnt down the house easily, we just got lucky.
And it was a family member, not one of the multitude of expensive electricians that found the short. He had encountered a similar problem in his old farmhouse.

Everthing else was ROMEX copper, but the well, water heater, and cook stove which were the 220v circuits.

Hopefully it was the old water heater that was your problem... maybe the element, but if not, this is another source of problems like that.

Good point. If you do have any aluminum to copper connections make sure they are well coated with NOALOX to stop the oxidizing which creates heat and leads to fire.

Your water heater was directly shorting out somehow, which tripped your main breaker.

The outside switch is a separate problem. Replace it.

Replace water heater.

Maybe replace main circuit breaker also.

Make sure you have multiple working smoke detectors in the house.

Last Edited by Butch DeFeo on 08/21/2021 05:45 PM

Sounds like you got ot OP.
I think we're all in agreement for the most part.
Water heater & a short backfeeding.

You asked to check the neutrals at your outlets...
I would not.
If it were me, after the water heater installation, if money isn't a problem, I would replace all the breakers.
Now most of them need AFCI protection anyway.
I would cinch down all conductors, neutrals & grounds in the panel.
I would check the groundbar and all dissimilar metal connections for corrosion & loose connection/bonding, and put de-ox on anything dissimilar.
I would definitely re-arrange your panel load balance as much as possible between legs, and check each leg to ground & neutral with a voltmeter.
To bypass worrying about neutral connections upstream(transformer etc.), just check your panel legs to ground, thenbto neutral at the main panel, or the meter as well.
If it's coming in @ 120 you're good.

Yes...I am replacing all of that. Going to test it and make sure nothing heats up when we kick everything back on.

Excellent advice. I will do this. Thanks.

The last thing I want is an electrical fire and I'm bleeding money this summer anyways...making repairs. Might as well bleed a little more before I patch the wound!

So...anyone who is interested in an update.

-Switched out the water heater and it fixed most of the problem. Changed wires and the ground. Even made it more accessible for yearly servicing.

-Today my buddy put in a whole new box, wires and a new ground outside. Moisture had been getting in the box and their were some broken wires. He was working with the live wire coming to the pole AND he is terrified of heights. He did it all without falling or shocking the shit out of himself...thankfully.

-He said to push it like crazy tonight to make sure it was going to work. Ran the washer, dryer, water heater, 2 AC units and most of the lights in the house at the same time. We hit 51 amps and nothing tripped. Went out to feel the breaker to make sure it wasn't getting hot and it was good.

-Fingers crossed...seems to be working.

-Just for the hell of it I'm going to have him update the inside with a new box and move some of the switches around.

Side note: He contacted the electric company because he had to remove the meter box to fix everything...they said they would come out in 16 weeks. Wtf? Long story short...I have no idea who cut the lock on the meter box.

Thanks again for all the help guys...much appreciated.