HVAC Inspection Checklist: What a Certified Inspector Actually Checks

A complete HVAC inspection checklist covers five areas: heating equipment, cooling equipment, ductwork and airflow, electrical and safety controls, and code or permit compliance. The checklist below is the actual sequence I work through on escrow inspections across Los Angeles and the South Bay — not a generic maintenance list, but what a NATE-certified inspector checks when a real transaction (and often a $12,000–$15,000 system) is on the line. Use it to inspect your own home, to prepare for a professional visit, or to understand what your general home inspector isn’t checking. Buying? Jump to the 12 HVAC items to check before closing.

What Does an HVAC Inspection Include?

An HVAC inspection includes testing the heating and cooling equipment under load, measuring airflow and duct integrity, verifying electrical connections and safety controls, and checking that past work was permitted and meets current California code. On an escrow inspection, every finding is photo-documented in a written report. The four checks that separate a real inspection from a quick look:

• Static pressure measurement — the blood pressure of the system; high readings reveal duct restrictions that choke performance and shorten equipment life.
• Refrigerant charge verification — an under- or over-charged AC can run for years while quietly destroying its compressor.
• Heat exchanger evaluation — cracks here are a carbon monoxide risk and the most expensive furnace failure.
• Permit and compliance history — unpermitted past installs and untested ducts become the next owner’s cost. Under California’s Title 24, that testing was called HERS and, for projects under the 2025 Energy Code, now runs through the ECC Program.

The Complete HVAC Inspection Checklist

Buying a Home in Los Angeles? 12 HVAC Items to Inspect Before Closing

If you are in escrow, these are the 12 HVAC items worth confirming before your contingency period ends. Some you can check on a walk-through; others need an inspector’s instruments. Each one either affects safety, changes what the system is worth, or becomes a negotiating point.

1. Equipment age. Read the data plates on the furnace or air handler and the outdoor unit. Age frames everything else, from remaining life to whether a repair is worth making.
2. Operation in both modes. Run heating and cooling. A system that won’t start, short-cycles, or blows lukewarm air needs a closer look.
3. Refrigerant type. The data plate shows whether the system uses R-22, R-410A, or a newer A2L refrigerant. It affects repair cost and replacement planning. See R-410A to R-454B and R-32.
4. Ductwork. Look for disconnected, crushed, or uninsulated ducts in the attic or crawlspace. Duct problems quietly waste capacity.
5. Airflow at the registers. Every room should get air. Weak or missing airflow can point to duct, blower, or filter problems.
6. Permits. Confirm recent replacements were permitted and finaled with the city or county. Our LA County permit guide shows where to check.
7. Condensate drainage. Check drain lines, pans, and overflow protection, especially for attic or closet units that sit above living space.
8. Filtration. A missing, wrong-sized, or badly loaded filter tells you about maintenance and can affect the coil and blower.
9. Refrigerant line insulation. Damaged or missing insulation on the suction line outside wastes efficiency and can cause condensation.
10. Electrical at the equipment. Look for a proper disconnect, intact wiring, and no signs of overheating.
11. Noise and zoning. Unusual noise from the outdoor unit or blower, and zones or thermostats that don’t respond, are worth documenting.
12. Visible installation defects. Improper venting, poor clearances, makeshift repairs, and corrosion on coastal outdoor units are common findings in LA homes.

When any of these turn up a problem, a written report with photos gives your agent something concrete to negotiate with, and a cost-to-cure report puts a price on the fix.

Can You Do Your Own HVAC Inspection?

Partly — and the honest breakdown matters. A homeowner can safely check filters (right size, snug fit, replaced within 90 days), clear two feet of space around the outdoor unit, confirm every register blows when the system runs, look for water around the indoor unit, listen for grinding or repeated start-stop cycles, and test the thermostat in both modes. What you cannot do without instruments and training: measure refrigerant charge, read static pressure, evaluate a heat exchanger, or perform combustion safety testing. Those four items are precisely where the expensive surprises live — which is why a self-check is good maintenance but not a substitute when money is changing hands on a home.

How to Prepare for an HVAC Inspection

Clear access to the furnace or air handler (closets, attics, and garage storage are the usual blockers), make sure the outdoor unit is reachable, have any service records or permits you hold available, and leave the utilities on — a system that can’t be run can’t be inspected. If it’s an escrow inspection, that last point is worth coordinating with the listing agent before inspection day; a de-energized system is the most common cause of a wasted trip.

Buying a Home? This Checklist Is the Inspection

Everything above is what our flat-fee HVAC escrow inspection documents in writing — $595 per system, photo-documented, with findings your agent can use to negotiate repair credits before your contingency period closes. It exists because general home inspections check almost none of this list in depth (here’s what HVAC inspections cost and why). We cover the South Bay, including Torrance and Redondo Beach. Agents and home inspectors: our referral program for real estate professionals is built around exactly this report.

HVAC Inspection Checklist FAQ