Our electric water heater seems to have burned out, but the breaker didn't flip off. My husband smelled an acrid burning smell in the house and traced it to the water heater, which is in the bathroom. He turned off the breaker. There had been signs the heater was failing and we had a new one on order -- age, rust drips on the outside of the heater, having to turn the hot water up during a shower. He couldn't find anything that looked like it had burned and the smell still lingers in the bathroom. He put a new heater in yesterday and it works fine. We're wondering what would have caused the burning smell and should we still be looking for the cause? Any suggestions?
Electric water heaters have 2 components that can fail and cause the burned smell. The thermostat is constantly opening and closing electrical contacts after years of operating the contacts get eroded and cause a higher resistance then they heat up and arc this is probably what happened the breaker won't trip in this case because it is not drawing any more amperage but the heat generated is at the contacts not in the rod and thus the smell. The other common failure is the fire rod itself they crack from heat cycling and short out this will normally trip the breaker but not always if they just open. The rod failure is usually in the tank so no smell is usually associated with this failure but the wiring and thermostat can smell warm due to the excess current if it shorted.