Cost of car AC repair

How does air conditioning work in a car?

In a technical sense, air conditioning works by forcing a refrigerant to change from liquid to a gaseous state in a pressurized closed loop.

To better understand this complicated process, here’s a closer look at each major component in an AC system and how it functions.

• Compressor: Functions as a power unit for the system and is attached to the engine via the serpentine belt. Compresses low-pressure gas into a high-pressure, high-temperature gas.
• Condenser: Uses moving air to rapidly cool the high-pressure, high-temperature gas, turning it into a low-pressure liquid. Generally mounted near the grille of your vehicle.
• Dryer: Contains a material (known as a desiccant) that removes water from the refrigerant.
• Expansion valve or orifice: Allows the system to bleed off pressure at a carefully measured rate and quickly lower the temperature. Turns refrigerant into a fine mist.
• Evaporator: Located behind the dash, the evaporator turns the liquid back into a gas in tubes. Air is blown over these supercooled tubes and into the cabin as cool air.

How much does it cost to repair a car air conditioner?

Car AC repair is generally more affordable than replacing components. However, repair costs will vary based on the extent of the work and the parts needed.

We talked with mechanics nationwide to get estimates for the cost of recharging the air conditioning systems and inspecting for leaks in our sample vehicles. Average costs for each vehicle averaged between $430 and $521, with most of the cost coming from labor.

How much does it cost to replace a car air conditioner?

Because car air conditioning systems have multiple components, it’s rarely necessary to replace the entire system.

The most common individual component that needs replacing in modern car air conditioning systems is the compressor. It’s possible for other parts to fail, but the compressor is the single most stressed piece of equipment in the system — and also the most expensive to replace.

According to Tom Bonfe, owner of Bonfe's Auto Service & Body Repair in St. Paul, Minnesota: “Compressors are never an easy cost to swallow. Although we are known for our cold, it gets very hot and muggy here in the summer. We have lines of people coming in when the heat kicks in to get their AC compressors replaced. If a customer doesn't have cold AC, this is the first place we look.”

Our survey of mechanics resulted in average compressor replacement costs ranging from $1,319 to $2,515 for our sample vehicles.

Symptoms of a bad car air conditioner

A faulty air conditioner can present itself in multiple ways; so, if you notice any of the following problems, your car’s AC could be to blame.

Not blowing cold air

Your AC may turn on and blow air, but if the air from your vents isn’t as cold as you’d like, it’s not of much use.

If your AC stops blowing cold air, it could be a number of possible issues:

• AC compressor is failing: Compressor issues are some of the most common failures in air conditioning systems. If the refrigerant is not compressed into a high-pressure, high-temperature gas, all other parts of the system will not work properly. Compressors usually fail because of a leak in the system or a lack of refrigerant. The refrigerant contains lubricant, and once it’s gone, the compressor will often fail due to friction.
• Low refrigerant: Over time, all AC systems will need to be refilled or “recharged” with refrigerant. This is normal and occurs because of the high pressure in the system. Over time, all cars will eventually need their AC systems recharged.
• Leaking refrigerant: Air conditioners are closed systems, and if their refrigerant is allowed to leak out, they will not be able to maintain pressure, causing the whole process to fail.
• Failing compressor clutch: Compressors are attached to the engine via a serpentine belt. The compressor clutch spins freely when the AC is not in use and activates when the compressor needs the power to operate. If the compressor clutch is failing, it will make an audible “clunk” when engaging the compressor, and eventually, it will stop functioning completely.
• Clogged condenser: Since the compressor needs surface area to operate, road debris or damage can prevent it from doing its job. It’s not uncommon to see condensers full of gunk, bugs and dirt when customers arrive at a shop complaining about warm air blowing.
• Faulty electrical system: Broken fuses or frayed wires can cause issues within the AC system because components are not being activated at the right times.

Foul or mildewy air

If the air coming from your vents smells, you may have a faulty drier or mold growing in the evaporator of your air conditioning system.

Loud noises

As mentioned above, when compressors or compressor clutches fail, they often make a loud noise that sounds like a clunk or a thud.

What if you have a warranty?

Air conditioners generally fall under bumper-to-bumper warranty coverage. So, if your vehicle is still under the manufacturer's bumper-to-bumper warranty coverage, a faulty AC component should be covered by the manufacturer at no cost to you.

You may also be able to dodge an expensive car AC repair bill if you purchased an extended bumper-to-bumper warranty for your vehicle. Just know that an extended auto warranty may require you to pay a deductible before coverage kicks in.

Michelle from Florida told us a $1,400 repair only cost a $100 deductible under warranty: “Everything went pretty well when I submitted a claim. The most expensive one that I had was my air conditioner. That was $1,400 and I spent 100 bucks for it.”

Based on the estimates we received for our sample vehicles, a car AC compressor replacement may not be enough to totally offset the cost of an extended warranty, but it can help you avoid an unexpected lump-sum payment. Plus, if you need another covered repair during your warranty period, you could come out ahead.

» CALCULATE: How much does an extended car warranty cost?

Should I repair or replace my air conditioner?

The right way to handle a broken car air conditioning system really depends on what your mechanic’s diagnosis is.

If your car’s AC is not blowing cold air but your mechanic says it’s because of a leak in the compressor line, then there’s no reason to replace the compressor. Repair should work just fine.

On the other hand, if your mechanic indicates that the compressor is faulty, repair isn’t really an option — you’ll need to replace the compressor with a new one. The good news is that there are very few scenarios that would require the replacement of your car’s entire air conditioning system.