Hot water heater issue
I just bought a used 2006 Adirondack camper and when I flip the switch to turn on the electric part of the hot water heater it throws the main breaker for the camper. I was assuming that it was the h...
Forum Discussion
DownTheAvenue wrote:
You are drawing more than 30 amps with all of that running by adding the water heater.
1400 watt water heater element at 120 volts = 11.66 amps
A/C running with low blower 1250 watts at 120 volts = 10.41 amps
Dorm refrigerator 375 watts at 120 volts = 3.125
RV refrigerator 960 watts at 120 volts = 8 amps
Converter 875 watts at 120 volts = 7.29 amps
TOTAL LOAD 40.485 AMPS
Now you know why the 30 amp breaker tripped
Without the water heater you were just under the 30 amp threshold, so when you added a big load like the water heater, you overloaded the 30 amp circuit and the main breaker did what it was designed to do.
Clearly there is too much current since the breaker is popping, but some of these numbers are way off.
A typical dorm fridge is, I think, somewhere around 100W running (but a lot more when the compressor is starting up).
An RV fridge is around 300W, not 960W.
The converter's power consumption is variable depending on the 12V load it's seeing. 7A or so is not unrealistic, particularly if the house batteries are low and being recharged. (Many converters have rather poor power factors, as well, which does not do the current consumption any favors.)
Since things seem to be working better with the replacement water heater element, maybe the old element was partly shorted and consuming somewhat more current that it should have been. It's not a common failure mode, but not beyond the realm of possibility.
