Mythbusters Blows Up Water Heater

They made another version for a 2 story house mock up.

Now that look like fun.

When I was in High School we were shown a very similar saftey film in shop class. You would of thought they had learned by now not to show kids things like that.

Jimmie

The house across the street turned into a rental upon the death of grandma. 1st renter installed an old wood cookstove in the basement that had a waterback. He didn't like the looks of the pipe stubs so he put pipe caps on them. First fire he wound up with shrapnel throughout the basement, fortunately, none penetrated to the first floor.

Harry K

Tony wrote in news: snipped-for-privacy@mid.individual.net:

A well laid out plan produces satisfaction. Ditch those pesky expensive parts!

Ol' Buster took a hard hit in that bathtub. He should gets a chek for dat.

The home where our pastor grew up was virtually destroyed around them early one morning when the water heater blew. His parents bed on the second floor was moved several feet and the main floor was basically demolished. Miraculously no-one was hurt.

Thre's a good reason they require safety over-temp and over-pressure valves today.

About a year ago the boiler blew up at one of the frat houses at OSU, and it effectively totaled the building. I'm not sure why the over pressure/over temp valves didn't release. It did a *lot* of damage and they condemned the building because of it.

I never watch that show but that was cool.

Wonder how many folk bother to check the safety valve every once in a while?

One in 500 trillion? If you open them to test, they usually leak.

Red Green wrote in news:Xns9CFA7E8DE5E32RedGreen@216.168.3.70:

Could the pressure in the tank push back against the cold water supply ?

Sure can, when my dad had a gas station we started getting steam out the water pipes. We found it was coming from the restaraunt next door.

Jimmie

My hot water tank is in the garage and the vent opens to let hot water run on the front outside entrance. A small screened area.

I open it to rinse and wash down the floor there and it doesn't leak. Perhaps it is because I use it on occasion that it doesn't leak.

Just saying it is not a one time use thing.

The heater in the video was configured to a worst possible case scenario, with all ports plugged and all safety devices disabled. In most homes there is a back flow check valve on the water supply, so there isn't much of any push back possible.

Even with some push back, if the water temp has gone high enough in the heater, when the system ruptures at any point, even a toilet supply line at the other end of the house, you still have a catastrophic depresurization, reduction in the boiling point of the water and flashing to steam situation.

I don't think so because water will not compress. Hence the term "water hammer". There would have to be another way for the pressure to release.

Actually, the pressure in the tank would indeed push back into the cold water supply. If there are any accumulators, they would buffer the pressure change. Otherwise, sooner or later (probably sooner) some over pressure valve somewhere will give, whether it is the one on your tank or your neighbors tank or some valve attached to the water supply. Your water lines in your house are not closed - they are open to the city supply, and all of your neighbors houses. Unless, like I said, there is a check valve somewhere. Unless you have, for example, a well. Then the pressure would push water into your accumulator (water tank). Since it is probably a small tank, your water pressure would rise until a check valve opens or something breaks.

In most municipal water supplies in North America, the answer is yes. In Zambia our water supply filled what was basically a "stock tank" in the attic and everything was gravity fed from there, so the "geyser" couls cause reversion flow without any trouble. In the hot season (3/4 of the year) we just turned the geyser off and got very warm water direct fron the tap. Needed to refrigerate water for drinking, unless you were drinking tea.

"Pete C." wrote in news:4b48fde5$0$12118$ snipped-for-privacy@unlimited.usenetmonster.com:

You make it sound so dismal. Good job:-)