House full of smoke

[Bluetick]

OK, with the garage door wide open, I lit the furnace. No smoke, really, when lighting. Throw some wood in and let it burn, leaving the garage door wide open. Forty five minutes later, I'm smelling smoke upstairs. So that furnace is getting all of outdoors to use for fuel-air and it's still back puffing. So I think it's looking more like the chimney is too short and partially blocked by the masonry chimney. What think you?

 

[Armstrong]

Did you get the chimney extended and get it figured out? If the Chimney height was the culprit, I would think that you would be getting smoke to start and not part way through. Also seems like you wouldn't be burning through the wood so fast...
Make sure ash pan gasket is very good and you experiment still with just the upper air control open. If the Chimney is causing any flow restrictions, air entering lower air supply would be spilling out upper air supply. Maybe even try that scenario for a bit to see if it does smoke

 

[Oldman47]

You need to look for what is keeping your house pressure low. It could be something you have overlooked like a bathroom exhaust fan or a stove exhaust fan that is drawing some air out of the house.

 

[Armstrong]

I agree that something else would be causing the smoking issue other than Chimney height. Have you found the culprit yet? Did you have the chimney extended?

 

[blades]

Got one of those Radon units Running? No one ever mentions them.