On Sun, 11 Jan 2009 19:45:35 GMT, aemeijers wrote:

(I like the sounds a furnace makes. Reassures me the damn thing is working.)

Funny you mention this: ours decided to take a vacation Friday night,
so Saturday morning when I got up at 6:30 and the house was 49F, I
called the installing company. Outside temps were single digits F.
Cold! Interestingly, apparently there was a sag in the exhaust PVC
piping that was backflowing some of the gasses and preventing the
pressure switches from engaging to give the motor the fuel needed to
heat the house, so the motor was running, but not heating the house.
$150 later, we seem to be all set. Whew. Then the snow started
coming down, so the timing was perfect.