Symptoms of a Bad or Failing AC Accumulator

AC Accumulator

Modern air conditioning systems are made up of several components that work together to provide cold air for the vehicle's interior. One of those components is the accumulator, also commonly referred to as the receiver/drier. The AC accumulator is a metal canister that acts as a filter for the AC system. It is filled with desiccant, a moisture absorbing material. It's purpose is to filter out any debris that may be flowing through the AC system, and to eliminate any moisture that may be present in the system. Any foreign particles or moisture that get pumped through the system can cause damage which can lead to corrosion, which can lead to greater problems, such as leaks. This is why virtually every AC system uses an accumulator, as they protect the system from such potential problems.

When the AC accumulator begins to fail, it will usually display a few warning signs. Taking heed of these signs so that the necessary repairs can be made will go a long way in ensuring that your AC system remains clean, moisture free, and functioning properly.

1. Rattling noises during operation

One of the first warning signs that an accumulator has failed is a rattling noise when the AC is turned on. Accumulators contain chambers inside, and a rattling noise may be indicative of internal damage to the accumulator potentially due to corrosion. A rattling noise may also be indicative that a fitting or hose may have come loose or suffered damage - a more serious problem.

2. Noticeable refrigerant leaks

Another more obvious and more serious sign that an accumulator has failed is a visible refrigerant leak. When an accumulator has failed and begins to leak, it will cause pools of refrigerant to form underneath the vehicle or in the engine bay if the leak is substantial enough. If the problem is not addressed in a timely manner, the refrigerant will eventually completely leak out from the system, which will completely disable the air conditioning until recharged.

3. Moldy smell when the AC is on

Another sign that the accumulator has failed is a moldy smell will appear when the AC is turned on. If the accumulator is damaged in any way, or is no longer filtering out moisture from the system, then the resulting moisture may result in mold and mildew buildup in the AC system, which will produce a smell.

As this component is essentially the filter that protects the entire system from contamination, it is important to replace or repair the AC accumulator as soon as any problems are detected. If you suspect that you may have a problem with your AC accumulator, or perhaps with something else in the AC system, this is something that a professional technician, such as one from YourMechanic, should be able to advise you with and repair as needed.

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

Car trouble?

Our mechanics make house calls.

  • Get a quote & book a service online
  • Save up to 30% compared to shops
  • Repairs, maintenance & diagnostics
  • 12-month, 12,000-mile warranty
GET A QUOTE

Excellent rating

Rating@3x

Need a mechanic?

Our certified mobile mechanics make house calls in over 700 U.S. cities. Fast, free online quotes for your car repair.

Get a quote

Post a question and get free advice from our certified mechanics.


Ask a question