HVAC inspection before buying a house

Do you need an HVAC inspection before buying a house?

Yes, if your home inspection report flags the furnace, air conditioner or heat pump as old, not working, or not fully checked. Book a heating, ventilation and air conditioning (HVAC) technician for an HVAC inspection before buying the house, inside your inspection window, not after closing. Your home inspector ran the system, but was not required to open the heat exchanger, test the refrigerant, or price the fix. The technician's written findings give you something specific to put in your repair request.

Key takeaways

• A written report can be an extra on some inspections. Confirm it is included, and its arrival date, when you book.
• If the house was inspected on a cold day, the air conditioner may never have been run.
• Ask the technician to test for carbon monoxide and to put a price beside each fix.

What does a home inspector leave for the HVAC technician?

Your inspector worked to one of two national standards. The one from the International Association of Certified Home Inspectors, or InterNACHI, has them run the heating and cooling with the normal controls. The InterNACHI standard does not require them to look inside the heat exchanger, or to check the system's size, capacity or airflow. For cooling, it also skips refrigerant and refrigerant leaks.

The American Society of Home Inspectors, or ASHI, has its inspectors open the access panels that open easily. Its standard still leaves out heat exchangers, and whether the heating or cooling reaches every room evenly.

Neither inspector has to price anything. InterNACHI excludes repair cost estimates, and ASHI excludes the costs of corrections. When a report line says "further evaluation," ASHI means a look by a qualified professional or service technician beyond a home inspection. For heating and cooling, that is an HVAC technician.

Which report findings mean you should book one?

Book the technician if the report says any of these:

• The heat exchanger, flue or venting was not inspected, or shows rust or backdrafting. This is a safety item. The Environmental Protection Agency lists leaking furnaces and furnace backdrafting among the sources of carbon monoxide, which it says "can kill you before you are aware it is in your home." Get the technician in before you talk money. A cracked heat exchanger is the worst case, covered in cracked heat exchanger on an inspection report.
• The system is old. ASHI inspectors must report systems near the end of their service lives. InterNACHI's life expectancy chart gives a furnace 15 to 25 years, a central air conditioner 7 to 15, and a heat pump 10 to 15, as a general guideline only. Read the age off the equipment's data plate.
• A system did not run, or was not tested. InterNACHI inspectors must report a heating system that did not operate. They are not required to run the air conditioner below 65°F outside.
• Rooms that run hot or cold. Sizing and balance are outside both standards, so the report cannot answer it. A technician can.

If you smell gas at the house, leave the area and call 911 from well away from the leak. The technician comes after that.

How much does an HVAC inspection cost?

Fixr puts the national average range at $237 to $430, and adds a travel fee of $27 to $50. Today's Homeowner puts a full inspection of heating, cooling and ductwork at $150 to $500 on average. Price moves with the system type, the home's size, and how much you ask the technician to cover.

You can also book one part of the system at a time. Fixr's ranges:

For a house you are buying, book the whole system. Fixr says a full inspection of every component can cost as much as $700, and many people get one when buying a home.

What does an HVAC inspection consist of, and how long does it take?

Fixr's standard checkup covers the electrical connections, refrigerant levels, ducts, blowers, filters, heat exchangers and condensate drain lines. The technician also tests airflow and efficiency. Most inspections take one to two hours. Afterward, the technician writes a report of everything they found, with recommended fixes.

Today's Homeowner lists a written report among the extras in pricier inspections. So when you book, confirm the report, the heat exchanger check and the carbon monoxide test are all included. Ask for a price beside each recommended fix, and ask when the report will arrive against your contingency date.

To prepare, send the technician the HVAC page of your inspection report and the equipment's age. Make sure the attic and any crawlspace with ductwork can be reached. Ask the seller for the maintenance records.

What can you ask the seller for after the HVAC report?

Put each HVAC finding, with the technician's price beside it, into the same repair request as the rest of your report. You can ask for the repair, a credit, or a lower price. What to ask for after a home inspection covers which lines are worth asking about.

Here is what an old furnace can add up to. Say the report lists a 22-year-old furnace. A full inspection at Fixr's range plus the travel fee is $264 to $480 ($237 + $27 to $430 + $50). If the technician says replace it, Today's Homeowner puts furnace replacement at $2,800 to $7,000, with installation, removal and labor. Together that is $3,064 to $7,480 ($264 + $2,800 to $480 + $7,000). The technician's written bid replaces these figures.

Get the estimate in writing, with the company name, the technician's name and the date. How to get repair estimates during the inspection period shows how to get a bid back before your deadline.

What if the seller says no?

You have three choices. Accept the house and budget for the work, pay part of it and ask again, or, if the work is too much, ask your agent or attorney what your contract allows and by when.

Before you accept, ask your loan officer whether the lender needs working heat or a repair done before closing.

What is the $5,000 rule for HVAC?

It is a rule of thumb for repair or replace. CBS News explains it: multiply the system's age by the repair cost. Over $5,000, replacement is often the better long-term choice. In its example, a 12-year-old air conditioner with a $500 repair scores $6,000. CBS calls it a starting point, not a replacement for a professional evaluation.

How do I know what my HVAC findings are worth?

The technician's written estimate prices the HVAC lines. The rest of your report still needs numbers before you send a request. Kept prices every line of an inspection report for $79, usually under 4 hours, and marks the ones that need a professional quote.

If the HVAC bid is one line of a long report and your window is closing, upload your inspection report to Kept and send the seller a priced list.

Sources

• InterNACHI, Standards of Practice for Performing a General Home Inspection
• ASHI, Standard of Practice for Home Inspections
• InterNACHI, Standard Estimated Life Expectancy Chart for Homes
• Environmental Protection Agency, Carbon Monoxide's Impact on Indoor Air Quality
• Pipeline and Hazardous Materials Safety Administration, Emergency Response
• Fixr, HVAC Inspection Cost
• Today's Homeowner, HVAC Inspection Cost
• Today's Homeowner, Furnace Replacement Cost
• CBS News, What is the $5,000 rule for HVAC systems?