Hot water heater issue

Question, over amperage. Can this be my cause? I never changed the breaker block when I went from my larger tank to my smaller tank. I presume the old one had a higher amp demand. It had a 30 amp breaker.

Running the numbers on a formula I found here: Water Heater Amperage? Maybe this is elec.

1500w/120V x 1.5 = 18.75 amp.

I’m no plumber nor an electrician? Just trying to act like one and learn some shit.

BTW, my breaker popped about an hour ago. 🙄
 
mbalbritton said:
Question, over amperage. Can this be my cause? I never changed the breaker block when I went from my larger tank to my smaller tank. I presume the old one had a higher amp demand. It had a 30 amp breaker.

Running the numbers on a formula I found here: Water Heater Amperage? Maybe this is elec.

1500w/120V x 1.5 = 18.75 amp.

I’m no plumber nor an electrician? Just trying to act like one and learn some shit.

BTW, my breaker popped about an hour ago. 🙄
Click to expand...
wait are you saying the new one draws fewer amps than the old one?
If so... thats not a problem by itself. The amps at the box are a max amount of current the device can draw before the box will trip, and (in theory) means the line etc are rated for that much to flow before its a problem. E.g. no big deal to only draw 18 amps on a circuit rated for 30.

That being said, if your device *should* only be drawing 19 amps at most (I assume this formula means that it puts out 1500w heat, the actual draw is higher (1.5x) bc of inefficiency, the difference between power input and power output) and it is tripping a 30A breaker then there is definitely a problem of some kind causing a high current draw. A high resistance would do that (and also kill a heater rod).
 
RatLabGuy said:
wait are you saying the new one draws fewer amps than the old one?
If so... thats not a problem by itself. The amps at the box are a max amount of current the device can draw before the box will trip, and (in theory) means the line etc are rated for that much to flow before its a problem. E.g. no big deal to only draw 18 amps on a circuit rated for 30.

That being said, if your device *should* only be drawing 19 amps at most (I assume this formula means that it puts out 1500w heat, the actual draw is higher (1.5x) bc of inefficiency, the difference between power input and power output) and it is tripping a 30A breaker then there is definitely a problem of some kind causing a high current draw. A high resistance would do that (and also kill a heater rod).
Click to expand...

Referring back to my previous post about not being an electrician, where should I be looking for potential issue then?
 
Spit balling here and not maybe related but depending on the age of the house it could be the breaker itself.
When we moved in they had just installed a new WH. Not long after getting settled we had a litter on puppies and were doing quite a bit of wash keeping bedding and wee pads cleaned. Started tripping the WH circuit. Thought it was weird so had a friend (electrician) over to check it out he tested the WH and it was fine. The breaker was toast (yes they do go bad). I called my realtor back who was friends with the previous owner and asked if they were having breaker issues and he said yeah and the water was hot but kept tripping the breaker. Plumber said it was the WH and it needed replaced. So they did. I’m 99% sure the old WH was probably good and a $15 breaker would have fixed the issue.
 
I have multi metered the water heater element and thermostat and all looks good there.

I tested my multi meter against a known outlet and get 120V. I test on the wires coming out of the wall to the heater (dedicated circuit) and I don’t understand the reading. It says “1”. Looking that up it says higher voltage than setting. I’ve checked on 200 V ac and 300 V ac.

Looking at the wires in the breaker panel, it’s wired 120V like most everything else in the panel.

I’m starting to lean towards the breaker too.
 
mbalbritton said:
I have multi metered the water heater element and thermostat and all looks good there.

I tested my multi meter against a known outlet and get 120V. I test on the wires coming out of the wall to the heater (dedicated circuit) and I don’t understand the reading. It says “1”. Looking that up it says higher voltage than setting. I’ve checked on 200 V ac and 300 V ac.

Looking at the wires in the breaker panel, it’s wired 120V like most everything else in the panel.

I’m starting to lean towards the breaker too.
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when you're taking these readings on the wall going into the heater, is the heater still on and connected etc? Where exactly are you touching the leads to?
I suspect that whatever is happening inside the contactor for the coil is affecting the reading. If you want to first just ensure you have proper volts to the unit you'll have to disconnect it and read only the line.

EDIT - it seems weird the WH would be 120v if its an electric heater. They are usually 240v unless it is really small.
EDIT 2 - I see you said it is only 12 gal. So maybe it is.
Just to be clear this is a 30A, 120v circut?

Post up a model # for the unit. I see its an AO Smith Signature 100. We can find out what the actual rated max draw is.
I'm becoming suspicious the breaker isn't allowing it to get the current it wants, either because the breaker is bad or something else (like a not great wire)
 
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mbalbritton said:
I have multi metered the water heater element and thermostat and all looks good there.

I tested my multi meter against a known outlet and get 120V. I test on the wires coming out of the wall to the heater (dedicated circuit) and I don’t understand the reading. It says “1”. Looking that up it says higher voltage than setting. I’ve checked on 200 V ac and 300 V ac.

Looking at the wires in the breaker panel, it’s wired 120V like most everything else in the panel.

I’m starting to lean towards the breaker too.
Click to expand...

Take a picture of how you have it wired in the junction on top of the wh. If you put the multimeter between the bk and wt or bk and ground you should have ~120v. The resistance of the element is what determines the amp draw and the tstat on the side of the tank obviously determines how long it is on, being a single element heater makes it even easier. Obviously the stat is working because otherwise there would be water on your floor. You sure there isn't 240 going to the wh?
 
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Ummmmm, I think I found it this time. Ya, apparently I’ve been running my 120V water heater on a 22
braxton357 said:
Take a picture of how you have it wired in the junction on top of the wh. If you put the multimeter between the bk and wt or bk and ground you should have ~120v. The resistance of the element is what determines the amp draw and the tstat on the side of the tank obviously determines how long it is on, being a single element heater makes it even easier. Obviously the stat is working because otherwise there would be water on your floor. You sure there isn't 240 going to the wh?
Click to expand...

Well… after some proper multimeter use 🙄 it does appear that I have 240 going to my 120v WH. I’m surprised it lasted 5 months to begin with. So it’s either a new WH or have an electrician come in and run me a 120V circuit, because clearly I don’t need to be doing that kinda work. :D
 
mbalbritton said:
Ummmmm, I think I found it this time. Ya, apparently I’ve been running my 120V water heater on a 22

Well… after some proper multimeter use 🙄 it does appear that I have 240 going to my 120v WH. I’m surprised it lasted 5 months to begin with. So it’s either a new WH or have an electrician come in and run me a 120V circuit, because clearly I don’t need to be doing that kinda work. :D
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Move the white wire from the two pole breaker to the neutral bus in the panel, make sure the wire and wh are rated for whatever that breaker is.
 
braxton357 said:
Move the white wire from the two pole breaker to the neutral bus in the panel, make sure the wire and wh are rated for whatever that breaker is.
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We need to see a picture of the circuit breaker wiring. If it's wired with the black to one side of the breaker and the white to the other, @braxton357 is correct (and the guy who wired it originally should be shot). If it's red to one side and black to the other side (like a 220V breaker should be) the white wire should already be on the neutral bus.
 
To be fair, the panel was wired correctly with the WH that was in the house. I went to a smaller WH and didn’t pay attention to the fact that the new one was 120V.

Looking at the panel it looks exactly like @braxton357 said. Love white wire to N Bus bar, swap double pole breaker with a single and a blank and hook black wire up to new breaker.

Pretty straight forward.

Breaker in question highlighted with laser pointer and the Bus bar in the second picture.

IMG_4783.jpeg


IMG_4784.jpeg
 
Couldn't he just add in a 20a 120 tap in place of the 220 and use that?
He's extra secure w over-rated wires now :D
 
Screw it. The dishes were piling up. I did it myself. The wife just had to sit in quiet solitude without Hallmark Christmas movies for 15 min. While I pulled, moved and reworked the panel.

All seems good. Even measured 120v+/- at the WH wires.

Nice to learn a new trick and walk away a little smarter. Thanks all!
 
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mbalbritton said:
Screw it. The dishes were piling up. I did it myself. The wife just had to sit in quiet solitude with Hallmark Christmas movies for 15 min. While I pulled, moved and reworked the panel.

All seems good. Even measured 120v+/- at the WH wires.

Nice to learn a new trick and walk away a little smarter. Thanks all!
Click to expand...
As long as it wasn’t this:

IMG_4235.gif
 
RatLabGuy said:
when you're taking these readings on the wall going into the heater, is the heater still on and connected etc? Where exactly are you touching the leads to?
I suspect that whatever is happening inside the contactor for the coil is affecting the reading. If you want to first just ensure you have proper volts to the unit you'll have to disconnect it and read only the line.

EDIT - it seems weird the WH would be 120v if its an electric heater. They are usually 240v unless it is really small.
EDIT 2 - I see you said it is only 12 gal. So maybe it is.
Just to be clear this is a 30A, 120v circut?

Post up a model # for the unit. I see its an AO Smith Signature 100. We can find out what the actual rated max draw is.
I'm becoming suspicious the breaker isn't allowing it to get the current it wants, either because the breaker is bad or something else (like a not great wire)
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most standard WH locations are 220/240v. So if installed this 110/120v WH in the same place... Did you grab power off the 220???

EDIT: lol just finished reading the thread.
EDIT2: Someone suggested using only one leg of the 220 to power a 110 breaker box for the WH. If i recall right, that is not to code. But i see ppl do it all the time on patios etc.
 
^^^ That is funny.

I installed a supplementary water heater for my master bathroom addition; it is a Rheem 2000W 10 gallons and it is a 120V using a 30A circuit (and fed hot water from my 40 gallon on the other end of the house.) Generally these are not the main water heater for a house because of the capacity and recovery rate but anything can happen I suppose.
 
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