Here's another Home Despot Rheem electric water heater story; rental house water heater reported as a problem. Loud popping (*described as firecrackers going off in the wall). I figure it's just sediment in the bottom of the tank has concluded the lower heating element, and the air bubbles boiling off. I drop by HD and pick up a replacement of the same type as last time. Last replacement was 10yrs ago, with a 10 year warranty...
Get there and unload, power it back up, and BANG! Sparks flying out of the wall connection. Here's what I found there:
Over time, the circuit resistance caused the wire nuts to melt, shorting out one of the legs to ground! Got that fixed up with better materials and clean splices, and figured it was prudent just to replace the heater anyway, since it had been 10 years, it's a rental house, and I don't want calls in the middle of the night.
The renter and I plumbed in the replacement, rolled the old one out to the curb, and I applied water pressure. As the tank filled, once the water level got up to the lower heating element, the seal started leaking. I shut it all down, pulled the lower heating element, and whoever put it in didn't lube the gasket and wrapped the sealing ring around the element threads...
Another trip to HD. And come to find out they don't just sell the sealing gasket without selling you a heating element, too. At least now I have a spare if I ever need one.
So far, going strong. Rheem sets their manufacturer warranty on the length of the anode rode inside the heater. Depending on use and water hardness, the warranty ends up pretty close to failure of the anode, followed by a tank hole, but nobody ever changes anode rods, do they?