Clicking Noise When I Turn On Heat in Car: Normal or Problem?

Does your car make clicking noises whenever you turn on the AC? This is an issue many seasoned drivers have encountered at one point or another. New drivers can also encounter the problem, which can affect any vehicle at any time.

Our article today investigates why a car can make a clicking noise whenever the heat is turned on. We further look into when this noise is likely to be heard or occur. By reading this article, you will know whether this clicking noise is normal or a problem to be solved immediately. You will also know whether you can continue driving your car and, if so, for how long.

What causes a clicking noise in my car when the heat is turned on?

A clicking noise coming from the car's AC system is not something many drivers would expect to hear. In many circumstances, many drivers, on hearing a clicking this noise, assume it will go away on its own. Many times, the clicking noise remains stubborn or even grows into some other bigger problem if ignored.

The main reasons known to cause the clicking noise whenever the heater in the car is turned on are;

1) Faulty blend door actuator

The blend door actuator is mandated to control the vehicle's climate control system. The actuator will determine which vent the air blows through. It determines whether the blend door remains closed or open. It will also control the intensity of airflow through the vents.

A blend door actuator is actually an electric motor and is quite small. Newer cars have more than one actuator. If your car has second-row climate control vents, then two blend door actuators are present.

When a blend door actuator malfunctions, you will likely hear a continuous clicking noise coming from the dashboard area when you switch on the heater. Other times, you might hear a knocking noise or some other strange noise. Besides the clicking noise, another symptom that points to a faulty actuator is irregular airflow and wrong air temperature coming out of the vents.

What causes the blend door actuator to malfunction?

The blend door actuator contains several plastic gears. Over time, these gears can get stripped or broken. The door gets stuck, and the motor skips repeatedly over a small nylon gear to try and move it to the correct position. When this actuator is damaged, a clicking noise can be heard in the dashboard area.

How to resolve faulty blend door actuator problem

The blend door actuator is a small device usually located at the center of the dashboard. You will need to know what the actuator looks like and where it's located to resolve issues relating to it. Replacing it is the most logical option because of the damage this component usually incurs. If you don't know where the actuator is located or how it works, it is best to seek the help of a qualified technician.

A blend door actuator should cost you around $20 or less. Your warranty cover can cover it depending on your car's warranty level. If you have some technical know-how, it might not be worth your time to wait in a queue to have the actuator going for $15 replaced.

A clicking noise when you turn the heat ON should not overly worry you if there are no other symptoms. A combination of clicking noise and the wrong AC temperature in summer or winter means you need to attend to this issue immediately. In many cases, however, the clicking noise is unaccompanied by other symptoms. While this is a relief, you should not drive the car for long before solving the clicking noise issue, as you might end up with a dead AC system eventually.

2) Compressor cycling on and off

The air compressor is the heart of the air conditioning system in your car. To regulate the air flowing and the temperature, the air compressor switches on and off. So switching the compressor from off to on and vice versa is normal. While going through these cycles, there will be a quiet clicking sound.

When the car compressor makes a loud clicking sound, it is time to be concerned. Rapid loud clicking noise, especially when the motor comes on, may mean debris is interfering with the motor workings. This may cause the compressor to be switching from off to on in a matter of 5 seconds.

A clicking noise from the compressor is normal when you turn on the AC. The clicking noise is an indicator that the compressor is engaged. The presence of sufficient Freon gas causes the compressor to make that clicking noise. If the gas is low, the compressor will not engage.

Solution

Even though the compressor will normally make a quiet clicking noise every time it switches to the ON position, this noise should not be rapid or loud. When such noise is noted, take your car to a professional service.

3) Worn out clutch

The AC system in your car sources its power from the engine via the serpentine belt. The serpentine belt is connected to the compressor pulley, which makes the clutch engage and disengage. Over time, due to the numerous movements, the clutch wears out. Toward the end of the life of the clutch, you will start hearing a clicking noise, mostly when you turn on the AC.

Solution

The clicking noise made by the clutch is solved by replacing it. A professional is best placed to help you replace this crucial AC component. If you ignore the clicking noise made whenever you turn on the heat in your car, you will eventually start hearing a rattling noise which can only mean more problems. You may end up with a seized compressor or a worn-out pulley when you ignore this clicking noise.

Is clicking noise normal when you turn the AC heat on?

The AC system is designed to run smoothly without making loud noises. When you hear a clicking noise, it means there is a problem. The good thing about the clicking noise when the heater is turned on is that it is unlikely to be associated with any catastrophic damage.

As highlighted above, a clicking noise made by the AC system can be caused by a faulty blend door actuator, a malfunctioning compressor, or a clutch. In most cases, the clicking noise should not be a reason to panic in the initial stages. However, when ignored, the clicking noise can become a big problem that will cost you money and time later on. In many cases, however, delaying to correct a clicking noise issue will lead to the AC blowing the wrong type of air.

Whenever you hear a clicking noise when the car AC is turned on, it is best to seek professional help immediately. If you have some technical auto knowledge, you can use a diagnostic machine to help you locate the source of the noise. The highlighted causes will help you to locate the source of the noise with ease. An OBD II scanner makes the procedure even easier because you can read the trouble codes and move on from there.

What to do to prevent the problem?

• Driving your car leads to wear and tear of parts and components of systems. You will likely experience wear and tear of AC system parts after several years of car usage. So, several systems and parts of your car should be expected to deteriorate or fail over time. For the most part, you can do nothing to prevent normal wear and tear as the car has a general lifespan, and that's why the warranty can only cover you for so long.
• Despite the fact that the AC system parts age and deteriorate in their performance over time, there are things you might be able to do to prolong the life of the above parts that cause a clicking noise whenever the heat is turned on.
• There could be debris in the system, making the AC perform below optimal capacity. This then causes the compressor to keep switching to the ON and OFF position hence the clicking noise.
• Very harsh weather will cause the blend door actuator to fail prematurely. This is because extreme weather makes the plastic gears in the actuator warp and even break. Inspecting the AC parts, especially the actuators, occasionally might help prevent you from running into this clicking noise problem.

Conclusion

In our article, we have explored why your car may be making a clicking noise when the heat is turned on. As mentioned earlier, the clicking noise will likely be made in an older car than a newer one. It is, therefore, safe to conclude that the noise is more of an old car issue than newer ones.

Solving the clicking noise problem is easy and takes only a few minutes. For the DIYers, solving their problem is easy too, but one must know what they are looking for. It is advisable to have an OBD II to help easily locate the problem. If the clicking noise is resolved on time, it should cost you little cash and time.