On 11/20/2012 9:30 AM, Home Guy wrote:
harry wrote:

The gas air mixture has to be right to get a good explosion.
This can't be guaranteed before ignition takes place.

If you have a gas leak in the basement, I garantee that somewhere in the
house the mixture will be perfect, and that somewhere will change over
time as more gas fills the house.

And a source of ignition has to be provided somehow.

The occupants of the house probably turned down the thermostat to
somewhere between 60 and 65f before they left.

This would be a clever way to set off the explosion.

The furnace is working, the house is sitting at 70f. You set the
thermostat to 65, you create your gas leak near the furnace, and you get
everyone out and go to the casino where you'll be spending the night.
It will take hours for the house temp to fall to 65, and all the while
the house is filling with gas. You turn off the water heater (or dial
it down to some low temp so it doesn't come on).

The house cools, the thermostat kicks in, the furnace ignition comes on,
then BOOM.

And, so what if it doesn't "go boom!" but just burns to the ground? The
(presumed) objective to have a reason to file an insurance claim has
been achieved...

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