What to Do While an Air Conditioner Releases White Smoke?

Imagine you’ve got home from work and switched on your air conditioner to make the room cooler, only for the AC to start blowing smoke. I’m assuming you will shut it down immediately before the question ‘why is my air conditioner blowing smoke’ hits you.

Your air conditioner blowing smoke can be nothing or a sign there is a problem. It can be caused by high humidity inside the unit, a clogged drain line, overheating, worn-out components, or an electrical failure.

You have to troubleshoot these common causes to know the exact cause and solve them. The best part is that I have prepared this article to give you the easiest time dealing with the air conditioner blowing smoke.

Why Is Your Air Conditioner Blowing Smoke?

An air conditioner does an excellent job keeping our homes cool during the summer. It does this by combining several components that work in harmony to ensure you stay cozy.

However, at times, a problem may arise and create a sign to tell you something is wrong, and this time that sign is smoke. It’s up to you now to notice it and take the necessary step.

The best approach is to diagnose the problem and fix it as soon as possible, and the whole process starts by identifying the problem and picking the right solution.

Here is a list of the common issues that make your air conditioner blow smoke.

1) Humidity

If the amount of humidity in the air conditioner is lower than that around the air vent or the registers, there is a chance you will see some fog forming.

The whitish smoke is vapor caused by the moisture reaching its dew point. The fog is odorless, and it does not pose any immediate heal risk or a problem to the air conditioner.

There is no need to get concerned or call a professional. You can solve the issue by running the unit on high for a couple of minutes to help achieve the AC interior humidity and outside humidity to reach equilibrium.

However, if the smoke doesn’t disappear or keeps happening, you’ll have to troubleshoot the problem further by inspecting the air filter.

A clogged air filter restricts the airflow, preventing the equilibrium from happening. You want to clean it with clean water to remove all the dust and dirt accumulating on it before trying to run it on high a second time.

Typically, consider cleaning your AC air filters regularly and replacing them once every 3-months.

2) Clogged Drain Line

If your conditioner is still blowing odorless white smoke even after giving it time to reach equilibrium, there might be a problem with the condensate drain line, a very common problem with old ACs.

As air conditioners strip heat out of room air, they also remove some condensed moisture to form the water that drains out through a drain line. Typically, the condensate collects on a drain pan under the evaporator coil before flowing out through a drain hose to the outside.

With time, the air conditioner will accumulate dust and dirt that can find its way on the drain pan. And since the condensate flow isn’t strong enough to push this dirt and debris out, the accumulation can cause blockage and clog to the extent that no water is flowing out again.

When the cold condensate comes into contact with heat inside the AC, it turns into steam, and the blower fan blows it out.

Open the necessary covers and clean the drain line, including the drain pan and the drain hose, to ensure the water flows nicely to the outside. If it’s dirty, pour some vinegar or mild drain cleaner in the drain pan and allow it to sit for a few minutes. Using a Wet/Dry Shop Vac pull all the stuff out of the drain line.

3) A Worn Out Component

If your air conditioner is operating fine, but there is a funny noise, smoke, and a burning smell, it could be a sign that there is a worn-out component(s), especially if your air conditioner is a couple of years old.

The two common parts that could produce smoke when worn out are the fan belt available in the belt-driven fan and the fan motor. Typically, the smoke will have a terrible smell that can be toxic to you.

That’s why it’s crucially important you shut down the air conditioner if you notice the smoke and contact an HVAC professional to check it out.

4) Overheating

If there are no funny sounds, but your air conditioner is still blowing smoke with a strange smell, you have a more serious problem.

With air conditioners fitted with many electrical components, they require proper ventilation to keep them cool and prevent overheating.

If the airflow inside the unit is restricted, there is a chance of overheating, producing smoke and a nasty burning smell. If you leave it untreated, it can evolve into dark, smelly smoke, and you might even start to hear a strange sound.

One cause of this problem is a severely clogged air filter as it will prevent proper ventilation to the electrical components.

The best solution here is to get in touch with an HVAC professional and make sure the airflow remains high by regularly cleaning the air filters and the air conditioner.

5) Electrical Failure

The last possible cause of your air conditioner blowing smoke is an electrical failure. A faulty wiring or a short circuit inside the AC could cause a burn that can cause smoke and a burning smell.

The air conditioner might sometimes shut down on itself and fire up when you start it again. However, you shouldn’t operate it at all. With time the small problem will turn huge and increase the risk of causing a fire or an electrical blackout by burning out the fuse.

So, it’d be best to shut off the air conditioner entirely and call an HVAC professional to have a look. Be prepared for the worst; the damage might be too far gone and repairing the unit is more expensive than getting a new one.

How Can You Avoid Air Conditioner Smoke Issues?

If your air conditioner isn’t blowing smoke anymore or you’ve been forced to get a new air conditioner because of the damage extent, here are general tips that can help you avoid the problem entirely.

Clean or Change AC’s Air Filter Regularly

Cleaning an AC air filter is a simple process. All you need is to snap the air filter out of the unit and use clean water to remove the dirt and debris that accumulated since the last time you cleaned it.

Consider changing it if it’s too dirty or a couple of months old (3 months or more). Changing the AC’s air filter is also easy and cheap. A new air filter will prevent the unit from blowing smoke and better the air quality in your home.

Even though the recommended period to change your air conditioner’s filter is after every 3 months, it’d be best to check it regularly for clogging and clean or replace it when necessary.

Give the Air Conditioner Yearly Checkups

Get in contact with a local HVAC professional you can trust and contract them to perform yearly checkups on your air conditioner. If your unit is an older model, the frequency might increase to two or three times a year.

The checkups can help reveal the underlying problem before it becomes a severe issue in the long run. It’s always better to fix the problems on your schedule before they become serious and force the air conditioner to blow out smoke.

Size Your Air Conditioner Properly

Suppose you want to enjoy the highest AC efficiency and avoid intermittent AC operation that can cause humidity problems, get the right size unit for your home. An oversized model can exacerbate a water vapor problem. But the perfect size will save you from the problem, and allow you to enjoy its full potential without wasting money and energy.

Related Questions

Why is my air conditioner setting off the smoke alarm?

Your air conditioner setting off the smoke alarm is mostly has nothing to do with smoke. Some smoke sensor alarms have a feature for alerting homeowners of power surges. If the AC’s electrical setup is faulty, it can cause a power surge every time you start it. That will trigger the alarm, and you should take it seriously and call an electrician or an HVAC professional to have a look.

What does a bad AC compressor sound like?

A loud, high-pitched, or grinding noise is emitted; a smoky odor may also accompany that. If you hear this coming from your air conditioner, it’s likely your AC compressor has gone bad.