A furnace heat exchanger keeps dangerous gases out of the air circulating in the building. It's a must-have on any furnace ...
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5 Types of Furnaces and How to Identify Them

Gas furnaces generate heat by burning natural gas. They’re available in varying sizes and energy efficiencies and produce a ...
Venting rules change with efficiency — and mixing them up can lead to moisture buildup, heat exchanger damage, and dangerous combustion issues.