Q: a/c making boiling noise

asked by on May 04, 2017

When I turn on AC when its hot outside, I hear boiling noise. As if something is boiling near or behind the glove box. This does not happen when heater is turned on. Immediately noticeable when car is in hot sun.

My car has 135000 miles.
My car has an automatic transmission.

Hello, thank you for writing in. The noises you are hearing may in fact be bubbles in the system. If the refrigerant is low, there may be air caught in the system instead. As the air conditioner processes and vaporizes the refrigerant, the air processes differently, and makes the sound of bubbles. The best thing to do first, is simply to have the system recharged. Considering the circumstances, it is advised that you do not use an at home charge kit. These kits only connect to the low pressure side. To properly regulate the pressure, add refrigerant, and remove air, you need to hook up to both sides of the AC system (which requires a special set up). If there are other issues with the AC, you will be able to find them easier with it fully pressurized. For more help recharging the AC, contact our service department to schedule an appointment.

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