What is air conditioner damper

Usually, the popular parts of the air conditioner are the compressor, air filter, vents but in this article, we will discuss the least popular but more useful part of the air conditioner that is damp.

We usually think controlling airflow is very simple, as it can be done by adjusting the vent, but this is actually not that simple!

Generally, many air conditioner systems are equipped with dampers. In summer as well winter we sometimes face the issue of inconsistent airflow, that is actually due to a fault in your dampers that you have to fix as soon as possible to get the maximum performance of your air conditioner.

What are dampers?

They are designed like a plate or valve made up of galvanized steel that opens and closes to a particular extent so that the airflow remains consistent and continuously regulates the airflow through the duct.

What are dampers

Where are dampers located?

A perfect location to place the damper is the joint of ducts with the ceiling or any wall. It is the same place where the register is located. It is usually located around 4 to 6 feet away from the main duct and is closer to the central unit of the air conditioning system. Usually, manual dampers have a lever or screwdriver for the adjustment of these dampers.

Is it more efficient than that of vent ?

As it is very close to the main or central unit it can close the airflow more efficiently or it can redirect to somewhere else where you need.

HVAC dampers types

Due to the difficulty of adjusting dampers, HVAC has provided different systems in which zones of the house are divided and have common heating and cooling requirements. They are provided with separate thermostats ensuring max comfort and is more cost-effective and energy-saving.

Zone damper/volume control damper

Also known as VCD is an HVAC-type damper that divides the area into multiple zones and ensures efficiency and comfort. They are usually automated powered by electricity, vacuum, or air.

Advantages :

  • Cost effective
  • Less power consumption

Disadvantage :

  • Not reliable
  • Depend on single furnace

Fire Dampers

They are usually present in combination with the ducts of the fire compartment. They are also of HVAC  type to be used as a strategy to control fire. Under normal conditions they are open but in the case when exposed to heat the fractures get a link with each other and are closed.

Fire Dampers

Finding the dampers :

Before adjusting, finding the dampers is crucial step and challenging one.

In case of older homes :

In the case of older homes, there is a problem that they usually get blocked during the repairing process of the house or usually get blocked due to carelessness so the solution is that you should go for blueprints, but if you still fail then try to adjust the vents instead.

Absence of dampers :

You will notice that during installing air conditioners people usually skip this part due to the high cost and they think that their job can be replaced by vents. Usually, contractors place the vent as an access panel over the duct where the damper is used to be placed and this can be detected and found by throwing the light through the vent.

How to adjust automatic dampers?

After finding and locating the damper you can adjust it easily. It’s just like opening and closing the lever. Make sure you are adjusting the right part of the air conditioner, otherwise it would cause a problem. First of all label, the dampers mean to label the paths where the damper is directed and lead.

For example the rooms or kitchen. Some houses have automated dampers installed that automatically adjust the airflow according to the optimum need of the room. It is actually a hit and trial method in which you will have to face errors and mistakes too. Dampers may be manual or automated. Manual dampers are usually adjusted and controlled by a lever. On the other hand, an electric motor is used to operate automated dampers.

How to adjust automatic dampers

Why it is tiring and challenging:

It is somehow challenging and time-consuming because you will have to open and then close each damper to check whether which of the damper is closed or blocked and is not producing adequate airflow. And of course, in this scenario, you will, of course, need an assistant.

Tips for adjusting the HVAC dampers:

  1. After the identification of the effects of the damper, you should know the proper procedure for adjustments.
  2. You should know what to do to make the perfect airflow
  3. The labeling should be proper, otherwise, it would cause confusion
  4. Give adequate time to your damper to be adjusted
  5. Label according to the season too, it will alert you before the season change
  6. The increased selling price of your house
  7. You should always consult a professional
Tips for adjusting the HVAC dampers

Cooling the house:

Keep in mind that cold air will sink while the hot air usually rises due to lighter weight. And also keep in mind that the basement and lower portion of your house are usually colder as compared to the upper. So when the air conditioner is on and you want to cool the upper portion then you simply have to close the damper leading towards the lower portion of your house, the air will eventually move to the attic portion.

And if you want to cool the lower portion of your house simply switch on the air conditioner without changing the direction of dampers, the cool air will definitely cool and conditioned the lower portion.

Heating the house:

If you want to heat up your house, you will have to switch on the furnace. If you want to increase the temperature of the upper portion you will have to close the damper leading towards the lower portion or without changing the setting and adjustment of the damper warm air will rise to the upper portion. But if you want to warm up the lower portion then you will have to close the upper damper, this will lead to the warm air in the lower portion.


  1. It has more control
  2. Produce the right amount of hot/cold air
  3. It can efficiently redirect air
  4. Ensure the system to work more practically
  5. Can be used to cut off the supply of air in the area where it is not required.

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