# Legal disclaimer HVACBuddy publishes general information. **It is not engineering, tax, or legal advice.** ## Engineering and safety Sizing, equipment selection and duct design require a calculation performed for your house by a qualified professional. Nothing here substitutes for a Manual J. ## Tax and incentives We explain programs; we cannot tell you whether you personally qualify. Eligibility depends on your circumstances. Consult the IRS, your state energy office, or a tax professional. ## Electrical, gas and refrigerant work These require a licensed, EPA-certified technician. Pages marked professional-only explain the problem and what a technician will do — they are not repair procedures. By [HVACBuddy Editorial Team](https://hvacbuddy.shop/authors/editorial-team/). Last reviewed: 2026-08-18.