maybe it was a still incognito - Some are supposed to be low pressure just like a conventional system inside. Pressure relief valve must have gone south-if it had one.
I have often wondered how many people are burning a homemade system with the "know enough to be dangerous" engineer totally unaware that he was proudly exposing his family to a bomb. "Sure it had a safety valve...See the reciept from the scrap man". Up north in WI. I saw a homemade air compressor built from a large propane tank. Used to blow off farm machinery and fill tires. NO gauge,NO pressure switch and NO safety valve !! It ran till the circuit breaker tripped. I was informed that I new nothing as it's been like that over 20 year's.
True. Its a tongue in cheek response referring to the deodorant can vs. wood stove that can be found on FHC. Some kids blew up an indoor stove with it... It's been said that water will expand 1000 times when it turns into steam, therefore the horrific damage with the OWB.
Remember that vid - from somewhere in Europe- Few years back about 8 blocks from my shop homeowner with wood heater of some sort blew the roof off the garage- as well as taking most everyones windows out in the immediate vacinity. Don't have any details.
Steam is an awesome power! Water at 245 F at 30 lbs psi when instantly turned to steam has a expansion factor of 300,000 to 1. I run an open system that operates at static pressure.
The more efficient units are not open systems. But..... There's got to be fail-safes. Relief valve and a failsafe that will melt, and dump pressure if it gets too hot.
I'm wondering if calling the local fire department would give us some answers. A t&p valve is only reliable if it's occasionally seen some love, how many people have put a bucket under the one on their water heater. Hmmmmm, be honest now. Now how many people will go and give it a tug just to find the green mineral laden gizmo won't shut off.... HONEY !!!! ANOTHER BUCKET !!!!!!! HURRY !!! O #$@& that's hot $#&@ !!!!
T&P valves never shut off !! Not even new...I won't touch them. When the cities go through and put new water meters with check valves in, everybody has trouble with the T&P valves dripping. The only cure is an expansion tank on the water heater.