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Why is My Car AC Blowing White Mist?

Why is My Car AC Blowing White Mist?

The white mist that comes from the air vents of the car can make the driver panic during driving. The issue mostly comes in hot, dry, and humid weather.

Why is My Car AC Blowing White Mist? Your car AC can blow white mist due to faulty belt-driven fans or motors, overheating or failure of internal components, and electric issues. The issue also occurs due to condensation reactions, clogged air filters, water accumulation in the heater box, and leakage of the heater core. 

You should check the circuits and electrical components when this white mist comes with a burning smell and stop your car.

Failure of fan belts and motors

The AC cooling fans are in vehicles to produce air from the vents. Sometimes these fans become faulty due to electrical issues in their component.

The long-term exposure of dry air to moist air triggers the condensation process. As a result, you can see the humid white smoke coming from the air vents.

It is problematic because it builds up on glass windows and decreases visibility. In addition, the use of cooling fans worsens the situation and causes fog to build on windows.

You can fix this issue by blowing the fans at high speed to better air circulation and decrease the humidity problems.

These are belt-driven fans and contain motors that are prone to wear and tear with time. The failed motor disturbs the functioning of the cooling fan, and you have to replace it.

Removing the dust and debris from their internal parts is also necessary to keep these fans clean.

Moreover, you can also check the relay and replace the blown-out fuse to keep this part functioning.

Overheating or failure of internal components

The white mist with a burning smell produces from the air vents due to overheating issues or failure of one or more components.

You can feel the typical smell because of the failure of belt-driven fans or the motors. In addition, the electric component needs a power supply for its functioning.

Overheating occurs in these electric components due to overuse and improper ventilation system.

Turning off the unit when you feel this smelly white mist from the vents is essential because these are toxic and also become intense with time.

It is better to park your car on the side of the road and not drive more because overheating can damage the other components completely.

Search the nearby service centers by opening google Maps from your mobile phone and take your vehicles there.

You can also cool down the system by not driving it for several minutes and parking in a shady or cool area.

Furthermore, it is necessary to replace the malfunctioned components and invest in them to fix the problem.

Condensation reaction

The condensation reaction is the most common reason for misty white smoke from the air vents. However, you can also feel the misty odor while sitting in your car’s interior.

The condensation reaction occurs when warm or dry air comes in contact with cold and humid air.

Fog formation occurs due to a decrease in the dew point of the ac unit from its optimal level.

You can fix this by inspecting the unit’s different parts regularly. Proper service and inspection are essential to reduce the formation of steamed vapors.

Take your cars to the service centers after every 2 to 3 months for service of air. Furthermore, you do not need to get worried if you face this issue during driving.

Turn on the cooling fan at high speed to cool the air in the cabin’s interior at a faster rate and reduce the humidity and fog formation.

Clogged air filter

The accumulation of dust and dirt in the internal components of the air conditioning unit ruins its functioning.

You can feel the white smoke coming from car vents due to a clogged air filter and compressor unit.

The dust and dirt present in air filters during the air filtration process. The air from the outside environment contains dust and other small particles that can clog these filters.

The blocked air filters disturb the equilibrium of hot and cold air. As a result, long-term warm air with cold air increases the humidity and aggravates this situation.

It is necessary to keep both types of air in equilibrium conditions and decrease the formation of steam. Clean the air filters after several months to remove dust and debris from the service.

Take out the cabin filters, hold them in your hand and blow the air through them. You can also wash them in water containing mild cleaning detergent for 3 to 4 hours.

Take a soft brush and remove the dust and debris with it by gently rubbing it on the filters.

Electrical issues

Ac is the electrical unit with wiring, relays, and circuits for proper functioning. The white mist with a pungent smell comes from the vents due to the burning of these electric wirings and internal cables.

You can also face this issue due to a blown-out fuse or bad relay switches. The burning of the electric component occurs due to overheating and fluctuation in the voltage supply.

Check the electric component and wiring if you feel a strong burning smell from misty vapors. Change the poorly insulated or damaged wires with new ones.

Moreover, it is also essential to inspect the ground wire for proper functioning. Locate the fuse box to remove the burnt-out fuse and install a new one.

Accumulation of water in the heater box

The accumulation of water in the heater box or ac unit increases the humidity, and you can see white misty smoke from the vents of your car.

The drain holes are present in the air conditioners to remove excessive water.

The blockage of drain holes causes this water to accumulate in the heater box and produce a condensation reaction or steam formation.

It is necessary to clean these drain pipes that are clogged with dust, leaves residues, and mildew. Locate the drain hole and remove the cap from it.

Collect the visible debris with your hand, and move towards the cleaning procedure. Take a mixture of vinegar and water in a bowl.

Run this mixture through the drain tubes for unclogging of debris and mildews. Wash it with clean water to remove the residues of vinegar.

Change the drain cap and turn on the ac after 30 to 40 minutes.

Leakage in the heater core

The heater core is the tube-like structure present on the inner side of the dashboard. The warm coolant is running in it before entering the engine.

The air also passes through it to cool the warm coolant before it reaches the vents.

The tiny hole in the heater core causes leakage of the coolant, and you can feel the sweet odor with white mist coming from the air vents.

You can also see the spots on the lower side of the dashboard due to leakage of coolant and antifreeze.

The coolants and antifreeze contain anti-corrosive substances and corrosion inhibitors to coat the components of the ac unit, including the heater core.

The decrease in the corrosive inhibitors corrodes the layer of the heater core and increases the risk of leakage through this pipe.

It is essential to fix the issue and reduce antifreeze leakage from the interior cabins. Recharge the air conditioning unit and add new antifreeze liquid to it.

The level of corrosive inhibitors decreases due to contamination. Therefore, change the coolant timely and add the new one to protect against rust.

In addition, several sealing liquids are available in the market to cover the tiny holes in the heater core.

Sealing the tiny holes with sealing liquids is a suitable option rather than spending on replacing the whole unit.

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