“I’ve been in the trade going on 33 years and I’ve never seen anything like it,” Klamath County plumbing inspector Dennis Stone told the paper. “It looked like a bunker-buster bomb went off in there, like in Iraq.”
According to Stone, the 20-gallon water heater’s pressure relief valve either corroded shut or failed altogether. While the thermostat continued to function, the pressure kept building up inside the tank until it exploded. It was hot enough to create steam, which means it was at least 220 degrees F. The pressure also blew out the garage door. No one was injured in the explosion.
The residents had heard noises from the heater before the accident and turned the water breaker off, as noted in the water heater’s instruction manual.