Hello, I have recently changed my old mercury stat with a new honeywell round stat; Problem I'm having is I have to turn the temp up to 80 to have the furnace kick on and the bottom temp is at 70-72, I have the switch on the inside where it suppose to be any ideas. Thanks Bob

What's the model of the stat?

You know that the furnace will start with no air movement before the fan kicks in? Are you seeing this or are you looking at the flame in the furnace?

What's the model of the stat?

You know that the furnace will start with no air movement before the fan kicks in? Are you seeing this or are you looking at the flame in the furnace?

Model#ct87k i have to turn the stat that high just to get the furnace to start

The manual is here:

http://customer.honeywell.com/techlit/pdf/PackedLit/69-1959EFS.pdf

If the system type is correct, then I would consider the tstat defective and call either the sore or Honeywell.

I wanted to see if there was the equlivelent of an anticipator which needs to be adjusted in mechanical stats. It's possible that the dial is out of calibration.