Living here in the Valley, your vehicle’s AC system gets used almost year round, and over time you may have noticed the air coming from your vents has a foul odor.
The main cause of this is the bacteria building up on the evaporator core due to the moisture in the system. The evaporator is located inside of the dash and looks like a radiator, but it has refrigerant passing though it instead of engine coolant.
While you may not realize it, your AC system not only cools the air coming into your vehicle, but it also removes moisture. This is why your AC compressor comes on when you also are using the defroster setting. When the air moves across your evaporator core that is being cooled by the refrigerant, the air cools and the moisture is removed. This is why, when it is very humid, you see the water dripping under your vehicle when the AC is on.
When your system is turned off, the evaporator still is wet from the moisture, and bacteria starts to form. Now, when the air moves across the evaporator, the smell comes with it and into the cabin of your vehicle. Most vehicles are equipped with a cabin air filter. Regular changes of this filter will help lessen the odor but will not eliminate it. The filter is mainly there to filter out dust and debris, but a charcoal infused filter will help with odor control.
To eliminate the issue, strong disinfecting foam needs to be applied to the evaporator to kill the fungi. The foam is injected into the evaporator housing and it penetrates into the fins of the evaporator. The foam kills the bacteria and will leave it smelling fresh. This should be an annual service, along with changing the cabin filter.
To help your evaporator stay cleaner longer, use your climate control in fresh air mode and not recirculation. Heavy use of recycled air causes a higher level of bacteria to form. You have either a fresh or recycled setting on the climate control unit, or you may have a Max AC setting. Use the fresh air or Non-Max AC option. Turn off the AC unit a few minutes before turning off the car. This will allow the evaporator to dry faster. Keep your cabin filter clean to allow maximum air flow.
As the case is with most maintenance items on your vehicle, the more proactive you are with your preventive maintenance, the fewer issues you will have with that system.
For more information, call H and I Automotive at (480) 985-9279. We are a full service professional automotive service center, serving our East Valley neighbors since 2009. Find us online at handiautomotive.com or on Facebook and Google+.