HVAC Red Flags for Homebuyers

When you walk through a home you might notice the kitchen, the layout, the backyard or how much natural light it gets. The furnace and air conditioner probably aren't the first things you think about.

But these systems are important. Replacing a furnace or air conditioner can cost thousands of dollars, so it is worth checking their age and condition before buying a home. 

Here are a few things to look for.

Start by finding out how old the furnace and air conditioner are. You can usually find the information on a label attached to the equipment. The serial number may also tell you when the unit was made. Furnaces and air conditioners often last around 15 to 20 years, although some can last longer with regular maintenance.

A furnace or air conditioner can look new without actually being new. For example, a newer thermostat does not mean the furnace is new. An outdoor air conditioner can also look clean even if it is several years old. Instead of judging the system by how it looks, check its age and ask about its maintenance history.

Take a quick look at the furnace and air conditioner during your home tour or inspection.

Watch for:

    • Rust or corrosion

    • Water around the furnace or air conditioner

    • A lot of dirt or dust

    • Damaged or loose wires

    • Burn marks

    • Strange noises

    • Burning or musty smells

    • Rooms that are much hotter or colder than others

One of these signs does not always mean there is a serious problem. However, several issues together could mean the system needs attention.

If possible, pay attention when the furnace or air conditioner turns on. You should not hear loud grinding, squealing or heavy shaking. The system should generally start and run without unusual noises.

A home inspector will usually turn the system on, check that it is working and look at its visible condition. They will also note its age and any obvious problems. However, some issues may not be easy to find during a regular home inspection.