replying to RichK, ExpressMechTech1 wrote:
Soot issues in these furnaces are caused by rusted or otherwise clogged burner
venturis. This chokes off most of the primary combustion air and you get
bright yellow flames and loads of soot. It is an order of magnitude worse on
propane models. Carrier is very good about warranty support on these but it is
important to choose a competent tech. The burners must be replaced also, and
again replaced if they ever go bad in future to prevent a repeat.

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