Chemical odor from central heating's chimney
I have an outdoor natural gas central heating unit (which also has a built-in AC). On the side of this large box-like unit is a small vent that outputs hot air/gasses. The odor of these gasses has a VERY strong "chemically" smell. Is this normal, or might there be excessive unburnt natural gas mixing with the normal heater vent exhaust? And can this be dangerous?
Answer to furnace vent odor...
To save anyone who may read this thread in the future: the smell from the vent was caused by poisonous gasses due to a cracked combustion chamber in the gas furnace.
There are only two solutions to this problem (that is, if you lived through the carbon monoxide poisoning that this issue causes): replace the combustion chamber (>$1500), or get a new central heating unit (>$4200).
PS: I'm really somewhat surprised that this HVAC forum didn't know the answer to this critical life and death problem...