New one on me...for the electricians

[trailerbikecamp]

SIL and her husband bought a new to them fiver this year. Last night when they got to the unit, sitting on a seasonal site,the water in the tank was already hot. The power switch for the tank was in the off position and propane tanks were both turned off.

Another friend had the exact same issue last night, but her hybrid TT was only put there yesterday afternoon. Same thing, power switch to hot water tank and propane were both off.

These 2 units are fed from the same distribution panel in the campground.

Both trailers had hot water before having their tanks turned on, using either electric or propane. Power is 120V, 30A typical rv outlet.

[ppine]

Reversing the polarity does not close the open switch leg.

[Old-Biscuit]

Captain_Happy wrote:
I've got a Suburban water heater with electric element. The water heater has no switch inside the water heater, it's fed from a breaker in the 120 volt electrical panel. The switch on the inside is for the propane only.

No way to find out if the 120 volt in feeding the element is to get yourself an volt/ohm meter and check it for power. Otherwise your just guessing

All Suburban Water Heaters WITH OEM electric element have an On/Off switch in outside compartment lower left corner behind/below gas valve.

Unless it has been removed by someone....

[Captain_Happy]

I've got a Suburban water heater with electric element. The water heater has no switch inside the water heater, it's fed from a breaker in the 120 volt electrical panel. The switch on the inside is for the propane only.

No way to find out if the 120 volt in feeding the element is to get yourself an volt/ohm meter and check it for power. Otherwise your just guessing

[westernrvparkow]

Wild guess, but I would check to see if the polarity at the 30 amp receptacle is reversed, simply because I don't like coincidences. Reversed polarity would cause power to be distributed to the heater even with the switch in the off position. There would still need to be some weird short or shunt to a ground or the neutral, but I guess it could be possible. One incident I would say failed switch. Two means I check the switches but also start thinking about other, weirder possibilities. A reversed polarity situation is somewhat common and easily corrected. To check, the hot side should be the left hand slot when looking at the receptacle. Use a multimeter/voltmeter to check the voltage between that slot and the U shaped ground. It should read about 120 volts. Then test the right slot to the U shaped ground, it should have no voltage. If they are reversed, the park wiring needs to be reversed. If both tests read 120 volts, there are bigger problems. That would be a good 2nd stop in your investigation.

[time2roll]

The law of conservation of energy in physics does not have an exception for RV water heaters.

[Old-Biscuit]

When you have eliminated the impossible, whatever remains, however improbable, must be the truth.


The water heater electric element was energized via a closed switch.

[ppine]

Maybe the water source was already hot.

[wa8yxm]

time2roll wrote:
The water did not self heat.

I recall one day in August when I was stuck in S.E. Ga (Townsend). and when it was time to take a shower I realized I'd not turned on the water heater (For some reason I'd turned it off,, possibly by accident, the day before)>> Still had a nice warm shower.

YES. it self heated. Sunshine can do that to ya.

[fj12ryder]

The electric power was on at the water heater, now you just have to find out which switch, or both, was actually turned on even though it didn't look like it. If the propane was turned off, that's the only way it will work.

[trailerbikecamp]

Both campers have a switch inside for gas and a second switch for electric. This is in addition to the power switch that donno0128 mentioned, that is on the tank itself.

The weather was warm yesterday, but the water temp was well above what the temp was. It wasn't steaming hot, but not far off it. It felt close to what our hot tub is, just for comparison. Ambient temp yesterday was 23C,(73F).

[donn0128]

sch911 wrote:

trailerbikecamper wrote:
Both tanks have a local switch at the tank and a primary switch inside the camper. The switch inside was turned off on both campers

I thought the inside switch was for gas and the outside switch was for electric. If the outside switch was left on it would explain this...

Generally speaking there can or cannot be a switch inside for the electric side. There will also be a breaker on the main panel. On my last fiver there was a 20A breaker, no inside switch and an outside switch because it was a Suburban water heater. If there is no inside switch and the outside switch fails in the closed position then the water heater will be on. There is only one sure fire way to prevent this, turn the breaker off before you leave.

[red31]

What temp was the water? My cabin's well water has a pressure storage tank in a small shed that gets very warm in the summer with little use. Same with the small unplugged hot water storage/heater indoors.

[time2roll]

The water did not self heat.

[sch911]

trailerbikecamper wrote:
Both tanks have a local switch at the tank and a primary switch inside the camper. The switch inside was turned off on both campers

I thought the inside switch was for gas and the outside switch was for electric. If the outside switch was left on it would explain this...