Bad Tpr Valve destroys the building


**[size=4]Bad Tpr Valve **

http://communitypress.ca/ArticleDisplay.aspx?e=2758242
**Explosion destroys cottage **

**Local News **

**Damage estimated at up to $200,000 **

Posted By Megan Abraham

Posted 1 day ago

Megan Abraham
Community Press
Marmora — A seasonal residence on Crowe Lake is being torn down after it was destroyed by a hot water tank explosion.
Central Hastings OPP and Marmora and Lake fire department responded to a call from a neighbour of the home at 741 Marble Point Rd. at 5:30 p.m. Sunday.
Marmora and Lake Fire Chief Tony Brownson said an all-day investigation Monday determined a 20-gallon hot water tank in the basement of the cottage was the culprit.
“The pressure relief valve failed, or there wasn’t one at all, then the element continued to heat the water, causing it to boil, which created pressure,” he said.
Brownson said an exploding water tank can have the same destructive power as dynamite.
The “shockwave” from the explosion lifted the entire home off its foundation, destroyed the interior of the home and blew out all of its windows, he said.
“The tank went through the basement ceiling, up through a bedroom, through a set of bunk beds with four mattresses, through the bedroom ceiling, the attic, out the roof of the home, and landed in the front yard,” he said.
The residence was vacant at the time of the explosion, which has been ruled as accidental
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Only a 20 gal tank. Imagine what would have happened if it had been a 333 imp gal tank or larger.
There would have been nothing but tooth picks left.
When water turns to steam it increase in volume 17 times.

The expansion ratio is actually 1700:1.

Rapid transition of superheated water to steam makes for a big boom.

Didn’t we see this on an episode of ‘Myth Busters’?
I wonder what the odds are for the simultaneous catastrophic failure of at least three separate systems at the same time? Judging by the lack of hot water tank explosions; not great.

I think this is more common then we see.
My Daughter in BC lived in a Condo and they had three go none as bad as this in about a year .
They then figured they should change the rest of the units after #3 .
I know the Home Inspector who inspected this 18 months ago.

Many people do no realise just how much distruction water can do when it flases to steam It can become a rocket .

http://www.google.ca/images?hl=en&q=exploding+water+heaters&um=1&ie=UTF-8&source=univ&ei=CBSTTM7ZOcOqlAf7oN2lCg&sa=X&oi=image_result_group&ct=title&resnum=8&ved=0CEYQsAQwBw&biw=1003&bih=527

I seen a water heater last year where the homeowner took the tpr valve off and installed a garden hose spiggot so he could wash his car with hot water…scary. I made a follow up visit with the homeowner to make sure it was corrected, and it was.