Re: Bad Alarm Installation Pictures

[Nomen Nescio <nobody@xxxxxxxxx>]

>Picture this. Cool/cloudy summer summer morning. Clouds break, temp
>goes up 15-20 outside, attic temp can easily jump up 30-40 degrees in
>far less time than the threshold of a rate of rise.
>Don't know where you're at, but in my neck of the woods, a 140 degree
>attic is not uncommon during July / August on a 95-100 degree sunny
>day.

Absolutely.  That's why you should only use rate of rise heads in attics if
they have a temperature rating of 190-200 degrees.  If you use 136 degree
rate of rise heads, you'll definitely wish you hadn't.

As I recall, the threshhold of a rate of rise detector is 15 degrees F per
minute.  That is, if the temperature increases at a rate less than that, it
doesn't go into alarm.  I don't think attic temperatures ever increase that
rapidly unless there's a fire, at least I've never seen it.  I've put lots
of 190 degree rate of rise heads inside attics and even skylights, and they
don't go off.

And if your attic is over 190 degrees, you have a definite problem. :-)

Think about the attic problems you've seen, and I'll bet the head was
popped, rather than causing an alarm and restore.  If so, that's not a
problem with the rate of rise portion of the head.

Rate of rise heads cover a much larger area than fixed temperature heads,
and they respond much quicker to a fire.

-  badenov