ANY OIL FURNACE EXPERTS OUT THERE

I got my issue with my oil furnace for my garage taken care of now im having issues with the one for the house. Every year i clean the furnace that in the house. Change the intake filters, take the nozzle assembly out & clean it, change the oil filter. This year i did every thing but change the oil filter. Also the nozzle was changed last year. Also this year i decided to take the duct work apart that goes to the chimney. Ive been here for 6 years & its never been cleaned. WOW it had alot of soot in it. The short piece of duct work that went into the chimney was rust off so got a new piece. Now as im putting it all back together the piece of duct work that has the barometric damper fell & the door fell off & the pins that hold the door on went flying. So i bought a new & installed it as the instructions said . OK for the problem. When ever the furnace starts it smells like its burning rich. I go to the basement & it has a slight haze that you can only see when you look at the ceiling lights. This furnace never did this before. The only 2 thing i can think of is 1 the oil filter needs changed or i didnt get the duct work into the chimney fare enough or to fare. I really cant aford to call a tech. Any thoughts ?

Heat Exchanger is shot, cracked and is letting the burned gasses into the interior of your home.

Time to replace.

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