bigchunk wrote:what is the three speed blower switch? maybe its set to number one instead of number 3 lets just say. and is there a question of putting a bigger blower on the unit? and also should he put a barometric damper into the pipe thats tied into his chimney he curently does not have one. he installed the harmon himself and no one told him about the baro and he acted like i was from planet zoom when i mentioned it. any input would be greatly appreciated.
A three speed would have 3 different RPM settings for the blower speed.
If it is a belt drive blower, it could have three different size pulleys on the motor and blower shaft and you could adjust the blower speed that way. That could possibly solve the air flow problem.
If the pulleys have different ODs, would switching them increase the fan speed? The big one on the motor will spin it faster.
The blower on the furnace may need to run at a different speed or is not sized properly. Keep in mind that if you are losing heat up the chimney, you will have more trouble keeping your plenum hot enough.
Review the baro stuff here; http://www.fieldcontrols.com/draftcontrol.php#draftwork
Anthracite pretty much requires a barometric damper, but wood units rarely mention baros and I'm not sure why. If he burns coal he definitely should have one. Get a draft gauge and use it no matter what you burn.
If I had a hot air furnace I would want a thermometer in the plenum and one in the stovepipe prior to the baro. The more info you have the better you can tune it. (actually, the more gauges and meters you can hook up to the monster, the more you scare the uninformed