Suburban Water Heater Tripping House Breaker

[Interex]

When I got my trailer home for the first time, I plugged it into my garage outlet (dedicated 20 amp) and it immediately tripped the breaker. After some troubleshooting, I figured out it was the water heater running in electric mode (switch outside turned on). When I turned it off, the breaker stopped tripping but I thought it was odd. Why would the water heater trip the breaker? I wasn't even running the A/C at the time but when I do run just my A/C, the breaker can take the load. Is the water heater really taking that much juice or do I have a bad electric element? I normally run it in propane mode when camping and turn on the water heater as well when I'm on 30 amp shore power. Not issues tripping the 30 amp breakers at the camp sites. Any ideas or is it common knowledge to not run water heaters in electric mode unless I'm on 30 amp power?

[Interex]

DutchmenSport wrote:
If the breaker is tripping when you run the air conditioner, then either the breaker is NOT 20 amps, or else it's getting weak.

Another thing... if you have anything running on that same circuit in the house, lights, appliances, devices) anything in the house on that same circuit, you could easily exceed the 20 amps. Make sure absolutely everything on that circuit is turned off in the garage.

It's not tripping when it runs the A/C so I figured it's something to do with just the water heater.

Old-Biscuit wrote:
Tripping service breaker for garage outlet.......
WH element is 1440W and can pull 12--12.5 amps
Add in converter especially when charging batteries

PLUS anything else on that garage outlet circuit???

But element would have to be energized (in heat mode) otherwise NO amps

With CB immediately tripping......bad element.
At least with a Suburban it is right there under burner tube in outside compartment vs on backside of WH tank like Atwoods

Nothing else on the circuit. Since it trips as soon as I plug it in, I'm leaning towards a bad element.

Toddupton wrote:
Is the element bad in the water heater? Was it full of water while it was turned on or was it empty?

Water heater was full when I plugged it in.

MEXICOWANDERER wrote:
MANY water heater coil failures short to ground. Disconnect wire from element. Turn breaker on. Ta Dah! Black & White diagnostic.

I was reading about that. I may try that. Thanks!

eHoefler wrote:
Length of exstension cord and size with dramaticaly affect it.

I was only running the 30 amp cord with an adapter on the end.

j-d wrote:
You "brought trailer home for the first time"... Is this a new trailer, new to you, or one you've had and used awhile?

Really shouldn't trip a 20 with a less-than-15 load, even with converter running. Maybe if your House Battery was also low...

Is your 20A breaker a GFCI Breaker?

Maybe weak breaker...

My gut is, failing element, but it's that, a guess.

We have 15000 A/C and basically we can't run electric water heater in summer with its 30A service. I replaced the 1440W element with a 1000W and it lets me run it sometimes. I try to run it at off times. Like when campground voltage is high, and when we don't need to run something else.

It's a new trailer to me but only a year old. The 20a breaker is not a GFCI.

I'm going to take a look at the ground wires and see if I need to replace the element.

Thanks so much for everyone's input!

[j-d]

You "brought trailer home for the first time"... Is this a new trailer, new to you, or one you've had and used awhile?

Really shouldn't trip a 20 with a less-than-15 load, even with converter running. Maybe if your House Battery was also low...

Is your 20A breaker a GFCI Breaker?

Maybe weak breaker...

My gut is, failing element, but it's that, a guess.

We have 15000 A/C and basically we can't run electric water heater in summer with its 30A service. I replaced the 1440W element with a 1000W and it lets me run it sometimes. I try to run it at off times. Like when campground voltage is high, and when we don't need to run something else.

[eHoefler]

Length of exstension cord and size with dramaticaly affect it.

[MEXICOWANDERER]

MANY water heater coil failures short to ground. Disconnect wire from element. Turn breaker on. Ta Dah! Black & White diagnostic.

[Toddupton]

Is the element bad in the water heater? Was it full of water while it was turned on or was it empty?

[Old-Biscuit]

Tripping service breaker for garage outlet.......
WH element is 1440W and can pull 12--12.5 amps
Add in converter especially when charging batteries

PLUS anything else on that garage outlet circuit???

But element would have to be energized (in heat mode) otherwise NO amps

With CB immediately tripping......bad element.
At least with a Suburban it is right there under burner tube in outside compartment vs on backside of WH tank like Atwoods

[DutchmenSport]

If the breaker is tripping when you run the air conditioner, then either the breaker is NOT 20 amps, or else it's getting weak.

Another thing... if you have anything running on that same circuit in the house, lights, appliances, devices) anything in the house on that same circuit, you could easily exceed the 20 amps. Make sure absolutely everything on that circuit is turned off in the garage.