Use the current rule
As of October 6, 2026, EPA's current residential and light-commercial systems table shows a narrow inventory exception: there is no federal installation compliance date for systems where all specified components were manufactured or imported before January 1, 2025. EPA's May 2026 reconsideration removed the earlier January 1, 2026 deadline for qualifying inventory. EPA current systems table, EPA May 2026 technical fact sheet.
That is not blanket permission for any equipment offered today. It also does not settle applicable Colorado requirements, Denver permitting, or the manufacturer's installation conditions.
Ask the installer to identify the applicable requirements and document why the complete proposed system qualifies. “We already have it in the warehouse” does not establish the manufacture or import history of every specified component.
Compare the actual systems
Request full outdoor-unit, indoor-coil, indoor-unit, and control model numbers, refrigerant designation, approved combination, installation scope, and warranty.
For a newer-refrigerant model, ask what its instructions require, whether any additional safety or installation components are included, and who will service it. Do not assume it can use an existing coil or be substituted without other changes.
For qualifying older inventory, ask about part availability, warranty start, service support, and whether the price advantage remains after all necessary installation work. Older inventory does not automatically mean a poor purchase, but it should have a documented reason to be your better option.
Avoid guaranteed savings or future refrigerant-price predictions. Those cannot establish the cost of your home's next repair.
Match the timing to your need
If your current AC can be repaired reasonably, that may allow a less rushed comparison. If cooling is unavailable, arrange a practical cooled space while proposals are reviewed. Do not let urgency eliminate compatibility or compliance checks.
Your next step is to request two complete options and the written eligibility basis for any inventory exception. Have the installer confirm applicable state and local requirements before you authorize the purchase. Then choose the package whose performance, support, and total price best fit your home.