Skip the auto shop - Our mechanics make house calls

What Components of the Heating and AC System Are Most Likely to Fail?

under the hood

The average automotive heating and cooling system (HVAC) is actually very complex, and they’re not connected to one another outside the cabin. Yes, your HVAC controls allow you to switch from warm air to cold, adjust the fan speed and more, but these are actually two completely separate systems and they operate independently of one another. As such, there are several components in both the heating and AC system that are prone to wear and tear and can fail over time.

Heating components

The most likely components of the heating system to fail are as follows:

  • Thermostat
  • Low Coolant
  • Heater Core
  • Radiator Cap (pressurized system)

AC components

The most likely components to fail in your car’s AC system are very different, and include the following:

  • Compressor and/or clutch (many cars use a combo unit that must be replaced if the clutch fails)
  • Low Refrigerant (caused by leaks in the high or low pressure side)
  • Serpentine Belt (drives the compressor and clutch)
  • Compressor Switch (controls compressor and clutch cycling)

While these are some of the most common parts of the heating and AC system to fail, they are just the tip of the proverbial iceberg. Your car’s HVAC system is complex, and requires a significant number of components in order to operate correctly. Professional diagnosis and repair is vital if you’re experiencing problems.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How Long Does a Throttle Return Spring Last?
Not all vehicles on the road feature an electronic throttle control (ETC), which is also called drive-by-wire. For vehicles that don't offer this system, they have a throttle cable instead that...
Insurance Requirements for Car Registration in Kentucky
The Kentucky Transportation Cabinet requires that all drivers in Kentucky carry liability automotive insurance, or “financial responsibility” in order to operate a vehicle legally and maintain vehicle...
Veteran and Military Driver Laws and Benefits in Idaho
The state of Idaho offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch in the...


Related questions

Q: My heater blows a lot of air it just doesn't get very hot

Hello there, a few common faults will cause your vehicle to have air that is not very hot. Without knowing the year, make and model of the vehicle I can only provide a broad answer. The most likely faults are...

Q: ac freon, still not cool, serviced, stil now cool, then looked at and given price high quote to replace leaking seal. Acceptable?

If an air conditioning system is empty, or not performing well, if it passes a visual inspection, the first step to diagnosing it is to do a vacuum and recharge. This process will involve a labor charge of 1 to...

Q: Heat turns cold after I drive for awhile. Got the water pump changed and the thermostat. Still having issues

If the cooling system gets low at all, usually the first thing you notice is that the heat goes away. The system could seem to be full, but have air pockets causing your problem. That can be solved by bleeding...