Have a coleman model DGAAD56BDTA with the blower setting on high and I am just getting cool air, I know blue is low and red med. And black is high but where do I make the connection switch at, to put blue where black is ?

What does it say on the board where the blue red and black are connected? Does it say heat, cool, fan.

Are you sure it's a fan speed issue, or is there possibly another problem. Does the furnace heat the house sufficeintly? Or are you having problems staying warm.

are you sure its a fan speed issue, or is there possibly another problem. Does the furnace heat the house sufficeintly? or are you having problems staying warm.

Keep warm but just load and windy, has a reg. or transformer on bottom with red blue black and white, then red and blue jump to top, red is on cool blue on heat

Black should be on cool, normally red is on heat, but you say blue(lowest speed) is on heat, therefor you will not be able to lower the speed any further.


Make sure all supply registers are open(if they are not, you will get too much flow from the ones that are, causing noise and draft) Also check filters. Good luck and please let me know how it turns out.

Wouldn't mind if you rated my answer.

black should be on cool, normally red is on heat, but you say blue(lowest speed) is on heat, therefor you will not be able to lower the speed any further.


Make sure all supply registers are open(if they are not, you will get too much flow from the ones that are, causing noise and draft) Also check filters. Good luck and please let me know how it turns out.

wouldnt mind if you rated my answer.

Yes the red is on heat and black goes to cool, out of the load transformer red goes to vac and blue to com, I never in 38 years had a furnace blow so hard, all vents are open fully, I think this would blow your hat off if you walked over a vent, has to be a blower control somewhere, thanks

DO NOT change the blower speed simply because you think it is loud. When changing the speed you have to take into account the heat rise across the exchanger (I think I'm starting to sound like a broken record). Too high and you will not get sufficient air transfer. Too low and your furnace can over-heat and go off on high limit and possibly cause irreversible damage to your heat exchanger. There is a balance and your furnace's nameplate will list the acceptable range.