TL;DR
Dual fuel is an HVAC configuration that pairs an electric heat pump with a gas furnace as backup, letting the system run the cheaper heat source for the conditions: the heat pump in mild weather and the furnace below a programmed balance point, often 25 to 40 degrees Fahrenheit. The furnace replaces electric resistance strips as the auxiliary, which cuts winter bills in cold climates with low gas prices.
What it means
Dual fuel is an HVAC configuration that pairs an electric heat pump with a gas furnace as backup, letting the system run the cheaper heat source for the conditions: the heat pump in mild weather and the furnace below a programmed balance point, often 25 to 40 degrees Fahrenheit. The furnace replaces electric resistance strips as the auxiliary, which cuts winter bills in cold climates with low gas prices. Controls must lock out simultaneous operation, since a furnace firing under a running heat pump coil can overheat it.
Where it sits in the glossary
Dual fuel is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
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