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Understanding 2009 multi stage gas furnaces and AFUE gains
The article explains 2009 gas furnace design shifts to multistage and modulating tech. AFUE rises toward 98 percent with condensing heat exchangers and plastic venting. It notes efficiency gains, cooler operation, variable speed blowers, propane conversion, and the need for compatible thermostats for optimal performance. It also includes a reader inquiry and author response from James Dulley.
MENTIONED IN THIS ARTICLE
Jim
Steven G
Steven