[QUOTE]Originally posted by jeffw_00
[B]I think the heat-exchanger on my 45 yr old Forced Hot Air furnace is beginning to go - we've had two CO alarms in the last month. I live in New England and am going to replace it.
SNIPPED a MISTAKE
6) By the way - my old system was a coleman "high-velocity' system with 4" ducts. I assume if i get an oversized (or A/C-sized) fan I should be ok. (I have a separate A/C system in the attic)
This is Turtle.
Answer to # 6 is a major Mess up in the making. The only way around the cure for this is to replace duct system or add on more duct to get you cfm to equal the tonage of the furnace heat and cooling. OR get the Manual D run and get ductwork to match it. You will never get a new residentiual furnace to put out the cfm need to supply the house with air through the 4" ducts.