Furnace Replacement: What a Complete Proposal Covers

Start with the home, not the old nameplate

A contractor should assess the home’s heating load and discuss changes made since the existing furnace was installed. New windows, added insulation, air sealing, or remodeled rooms can change the amount and distribution of heat needed.

Ask for the sizing method and the assumptions behind it. If the bid simply proposes a furnace with the same capacity as the old one, ask what supports that choice and whether comfort complaints or uneven temperatures will be addressed.

Make installation details explicit

Furnace type affects the installation: fuel supply, electrical connection, flue or direct-vent arrangements, combustion air, condensate drainage, and thermostat compatibility may all need review. Have the contractor identify what is included and what would trigger additional work.

A replacement can expose issues with an existing vent, chimney liner, return-air path, or ductwork. Ask how the installer checks those components and whether required safety testing and inspections are included.

• List equipment make, model, input/output capacity, and efficiency rating.
• Clarify removal, disposal, permits, inspection, startup, and warranty registration.

Compare bids on equivalent terms

ENERGY STAR lists certified furnace products, which can help verify a model designation; certification alone does not establish that the unit is correctly sized or installed. Compare the same fuel, capacity range, controls, venting scope, and included duct repairs across proposals.

Current local prices are unavailable here. Ask each bidder for a written total with exclusions, a work schedule, warranty responsibilities, and a plan for commissioning and handoff. Resolve differences in scope before treating the bids as comparable.