Furnace Installation & Replacement in Centennial

Centennial's elevation calls for about a 23% derate. A furnace with 80,000 Btu/h input at sea level runs at about 62,000 here once it has high-altitude orifices and correct gas pressure. We run a Manual J first and choose a model whose derated output meets the load. Finished basements in these homes often have one or two supply registers and no dedicated return, so we check that the ductwork can deliver what the new furnace produces.

Under HB23-1161, a gas furnace sold new in Colorado must emit no more than 14 ng/J of NOx or carry the current ENERGY STAR certification. ENERGY STAR Version 5.0, in effect since July 31, 2026, requires 97% AFUE in northern states. Your quote should say which path the furnace meets. Any compliant model we install in a Centennial home also gets the altitude setup described above. You can read more in our NOx rules guide.

Most 1970s and 1980s homes here vent the furnace and water heater together through a metal B-vent to the roof. An ultra-low NOx 80% furnace can often reuse it after inspection. A 97% condensing furnace needs a new PVC route, usually a sidewall near the furnace, plus a drain, and the water heater left on the B-vent has to be checked and often resized because one appliance in a vent sized for two may not draft well.

In the One-Stop process, a straight replacement doesn't need plan review, but any venting change still has to pass inspection.

City utility listings name Xcel Energy and CORE Electric Cooperative, with the provider varying by address, so check your bills before planning around a rebate. If Xcel is your gas utility, note that a rebate tracker reports Xcel dropped gas furnace rebates on January 1, 2026. Heat pump rebates depend on your electric utility. A $1,000 Colorado tax credit for air-source heat pumps plus Power Ahead Colorado's $1,500 for cold-climate models apply either way.

If your AC dates from the same era as the furnace, a dual-fuel system replaces both with one project and keeps gas heat for cold snaps.