Our Electric Rheem 40 gallon is in a closet upstairs. I was recently in the closet and, as I always do, glanced at the pan which the tank sits in. Just a habit-just in case. Well, on that day, there was about 3/8 inch of water in the pan. Not enough to begin flowing out of the drip line. I got a shop vac and removed all the water. I assumed the tank bottom had rusted out as there was no sign of leakage anywhere higher. I went back the next day and the pan was bone dry. Two weeks later, it’s still dry. Not a hint of moisture in the pan or anywhere on the tank. I can’t figure out where the water came from. There is no roof leak. No pipe leaking. The tank is in an insulated, heated area so is not sweating. And the heater is doing its job just fine. No sign of failure in any way. I’m at a loss as to the source of that water. The only thing I can think of was a quick pressure release? But if that happened, would the water flow down into the pan?

Thanks for your input.