Do I need a permit for HVAC work in
Gahanna, Ohio?

Gahanna HVAC permits — the key details

Gahanna's Building Department enforces the 2017 Ohio Building Code with amendments effective January 1, 2020. All HVAC work — installation, replacement, modification, or repair involving system components — falls under the mechanical permit category. The city defines 'mechanical work' in Title 13 to include furnaces, heat pumps, air conditioners, ductwork fabrication or routing changes, refrigerant line installation, venting terminations, combustion air supply, and any change to equipment nameplate capacity or SEER/AFUE rating. Like-for-like replacement is allowed only when: (1) the new equipment matches the old in tonnage (within 0.5 tons), fuel type, and mounting configuration; (2) all existing ductwork, vents, and flue pipes remain in place without relocation; and (3) no change in refrigerant type or electrical supply (voltage, amperage, or circuit). If you're upgrading from a 3-ton R-22 system to a 3-ton R-410A unit, you still need a permit because the refrigerant change requires new compatibility checks and evacuation documentation. Gahanna's Building Department is more conservative than Columbus on the 'like-for-like' exemption — they require a contractor affidavit confirming nameplate data and existing duct sizing before they'll waive the permit. Gas line work (new, rerouted, or upsized) always requires permitting because it triggers pressure-test and leak-detection inspections per NEC Article 422 and Ohio mechanical code. Even if your contractor says 'it's just a replacement,' call or visit the Building Department with equipment specs and a site photo to confirm exemption eligibility before work starts.