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Furnace Repair or Replace Calculator

Weigh furnace age, repair cost, and new furnace cost with a clearly labeled rule of thumb to lean toward repair or replacement.

Screening estimate only.A professional Manual J load calculation is authoritative for final furnace sizing and equipment selection. Confirm every result with a licensed HVAC professional.

Considered suggestion

Enter age, repair cost, and new furnace cost for a rule-of-thumb lean.

Fine Print and Sources

Screening estimate only. These tools use only the values you enter and simple planning math. A professional Manual J load calculation is authoritative for equipment sizing, room loads, and final purchase decisions. Confirm with a pro before you buy.

Method: this uses a common rule of thumb. When furnace age times the repair cost is greater than the new furnace cost, or when the furnace is older than 15 years, the tool leans toward replacement. Otherwise it leans toward repair. This is a considered suggestion, not a mandate. A licensed technician who inspects the unit makes the authoritative call.