AC & Furnace Size Verification Checklist PDF

✓Home & Climate Inputs+

Square footage entered is CONDITIONED (heated/cooled) floor area only — not garages, unfinished attics/basements, or porches
Climate zone selection confirmed against your actual location, not just guessed from general region
Insulation quality assessed honestly (attic, walls, windows) rather than defaulting to Average without checking
Sun/window exposure selection checked against actual window count, size, and orientation, not just a guess
Ceiling height measured for the actual room(s), not assumed at the standard 8 ft default — especially for vaulted/cathedral ceilings

✓Before Purchasing Equipment+

An ACCA Manual J load calculation obtained from a licensed HVAC contractor before purchasing equipment
Confirmed the selected equipment size isn't being oversized "to be safe"
If ducted: existing ductwork confirmed adequate for the new equipment's actual airflow (CFM), not just reused by default
Local permit requirements and electrical/gas line capacity checked before scheduling installation
Contractor's HVAC license and liability insurance verified before signing a contract or making a deposit

✓Efficiency & Equipment Ratings+

Furnace AFUE selection confirmed against the actual unit being considered, not left at an assumed default
Difference between the furnace's OUTPUT BTU (what heats the home) and INPUT BTU (what's on the spec sheet) understood before comparing units
Contractor quotes cross-checked against each other for the SAME sizing basis (Manual J, not a rule of thumb)
AC SEER/SEER2 rating confirmed against the current DOE regional minimum efficiency standard for your area

✓Installation & Safety+

Electrical circuit/breaker sized for the NEW equipment's actual amperage draw, not just reused from the old unit's circuit
Gas line sizing and venting confirmed adequate for the new furnace's actual BTU input, especially when upsizing
Carbon monoxide detector installed and tested near a new or replaced gas furnace
AC evaporator coil's condensate drain line confirmed sloped and clear, with a secondary drain/float switch installed where required
Outdoor condenser unit placement confirmed with adequate clearance (commonly 24-30 in on the service side) for airflow and future service access

✓After Installation+

System startup/commissioning performed by the installer, verifying refrigerant charge and airflow against manufacturer spec — not just powered on
Thermostat programmed and tested through a full heating AND cooling call before considering the job complete
Final permit inspection scheduled/passed where required, and manufacturer warranty registration completed

AC & Furnace Size Verification Checklist