Attic fan blows out water heater flame?

Two or three times in the nearly four years we've lived in this house I've had to relight the pilot in our gas water heater -- including this morning when we realized that our water was cold.
This afternoon I went into the utility/furnace room to get something and was greeted by a strong smell of gas -- and of course the pilot was out again.
Is it possible that this was caused by running the attic fan to get some air circulating in the attic while I did some work up there -- that the fan was sucking so much air down the water-heater chimney that it blew the flame out? The fan is mounted in the ceiling blowing air out of the house into the roof space -- and in this case out through the access hatch (in the garage) which was open. I didn't have any windows or doors open at the time.
Perce
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On Thu, 06 Sep 2007 20:11:24 -0400, "Percival P. Cassidy"

Yes. Don't do that. It's called down drafting, and not only can it blow out the pilot, it can suck carbon monoxide that is supposed to go up the chimney into your house. Never run the attic fan without a window open far enough to supply make-up air.
You have another problem. If the pilot goes out, the safety should shut off the gas, including the gas to the pilot. Get this checked right away. The alternative is rapid-disassembly mode.
HTH,
Paul F.
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First, that access hatch in the garage should be closed all the time. It is a safety feature. In the event of a fire in the garage it keeps the fire from rapidly spreading to the attic area and from there to the entire home.
The attic should be well vented. If not you need more vents.
Never run the attic fan without a lot of your windows open. It can cause the very problem you have observed. That problem is also a safety issue.
If you care about your family and your home, you will be more careful in the future.
--
Joseph Meehan

Dia \'s Muire duit
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On 09/07/07 05:58 am Joseph Meehan wrote:

The access hatch in the grage was open only so that I could get into the attic and work there. It's closed at other times.

Never previously having had a home with an attic fan, I had no idea what the rules for operation are -- no instructions next to the switch. Now I know.
Perce
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On Thu, 06 Sep 2007 20:11:24 -0400, "Percival P. Cassidy"

You have a bigger problem than the pilot going out if you are smelling gas. When the pilot goes out the gas valve should shut down all flow of gas to the pilot assembly. I'd get this checked before your house explodes.
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On 09/07/07 09:10 am Water Heater Dude wrote:

But isn't that a temperature-controlled thing? AFAIK, the pilot light heats a sensor that signals thats it's OK to let the gas flow. If the pilot light goes out, the sensor stays warm enough for a little while to allow a small amount of gas to flow.
There was no smell of gas when I relit the pilot yesterday morning, so gas is not continuing to flow the whole time.
I mentioned "a strong smell of gas", but I should point out that I have a very sensitive nose (many years working in a chem. lab) and smell things that others don't. (OTOH, my wife has a lousy sense of smell but hears things that nobody else does.)
Perce
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That sensor is called a thermocouple and it should be in the pilot light's flame all the time. They do fail and are easily replacable.
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On Fri, 07 Sep 2007 10:28:00 -0400, "Percival P. Cassidy"

You are guessing. Is your family's life worth a guess? You ar on a newsgroup asking for advice. Several people gave it to you, whether you follow it or not is entirely up to you, just make sure you have your life insurance paid up. Good luck with that.
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