During the night, the TP valve on our electric water heater went off. The noise, which sounded like a pressure cooker releasing pressure, woke us. It released a lot of water, but I have don't know why it happened. Can you tell me why and how to keep it from happening again?
Hi howard and Welcome to The Plumbing Page. at AskMeHelpDesk.com. T&P valves can open up for several reasons. All of which MUST be checked outr.
1- High house pressure. Do you have a pressure reducing valve (PRV) installed. If so what's the house pressure? The average is 45PSI.
2- High temperature. That's when the water turns to steam . That's what you describe in your post.
3- A faulty T&P valve. I don't think so.
It sounds to me like one of your thermostats went bad and powered up a element that produced steam. Shut the power off to the heater and either replace the thermostats or call in outside help. Good luck, Tom