Furnace

[Richard]

Pilot light is on. Burners will ignite. New thermostat. Will not come on still.

[Terry Coombs]

You mean the fan/blower ? There's a temp sensor in the heat exchanger that turns the fan on/off . Looks like a little box with a disc inside and some pointers on the disc . Try rotating that disc , carefully so you don't change the pointer settings . You ARE closing the blower box door aren't you ? There's an interlock switch there too that'll kill the fan .

[Dean Hoffman]

Does your furnace have a separate on-auto switch for the fan? Turn it to on to see what happens.

[philoÂÂ]

If you were the guy who posted before we all told you ...that was NOT the problem

[trader4]

Another post not worth wasting time on because there is no complete description of the problem, actually very little to go on. Amazing how people expect answers when they don't give the most basic info.

[Lab Lover]

If it is a hot water furnace, you might check the aquastat.

[Ed Pawlowski]

Then it would be a boiler

Furnaces heat air Boilers heat water

[krw]

Even if there is nothing boiling? ;-)

[Dean Hoffman]

Izzat what they call the power of positive thinking?

[krw]

Well, when we had one, I really didn't want it boiling.

180F, good. >212F *very* bad!