Combustion Air Vs Venting What Actually Controls Draft And Safety

How combustion air and venting differ and why both control furnace draft and safety, plus how to spot supply and exhaust problems in the field.

This guide is part of the HVACTools.pro library: practical, field-tested HVAC procedures and best practices written for working technicians. The full article renders when the page hydrates; the section below previews related material in the meantime.

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