Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. What Components of the Heating and AC System Are Most Likely to Fail?

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

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P0222 OBD-II Trouble Code: Throttle/Pedal Position Switch/Sensor B Circuit Low Input
P0222 code definition Throttle/Pedal Position Switch/Sensor B Circuit Low Input What the P0222...
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: No heat when ideling or driving slow.

The lack of heat being generated by your system may indicate a clogged heater core. The [heater core]((https://www.yourmechanic.com/services/heater-is-not-working-inspection) is a small radiator like unit that circulates the hot coolant from the engine through the heater core which then uses this...

Q: Car heater blowing cold air.

There are a few different reasons why your heater could be blowing cold air. First, there may be a problem with your Heater controls. Inside your dashboard there are a series of doors that direct airflow. If one of these...

Q: Service light on, high temperature, heat off

The only way to gain insight as to what happened it to retrieve the diagnostic trouble codes associated with the Check Engine Light. Even if the Check Engine Light is not on anymore, you may be able to retrieve history...