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.

Do HVAC dampers go bad

Yes, HVAC dampers can go bad and there is nothing extraordinary about that.

HVAC dampers are plates/valves that are responsible for stopping or regulating the flow of air in a duct.

Dampers are one of the many parts of an HVAC unit. Just like any other part of the HVAC system can malfunction or break down, the HVAC dampers can also go bad and malfunction.

There can be several different reasons why HVAC dampers go bad. Machines are machines, they are always working and their parts often malfunction or break down with time due to excessive wear and tear. Therefore, the HVAC dampers are no exception and they can also go bad with time.

Do you want to know how long your air conditioner damper can last? Let’s find out next.

How long do air conditioner damper last

20 Years!

The air conditioner damper can last for almost 20 years if you maintain them regularly.

Several different factors affect the lifespan of the damper of an air conditioner:

  • How much do you use the AC?

If you use the air conditioner a lot then the life of your HVAC damper might decrease due to excessive use plus wear and tear.

But if you don’t use your AC much frequently then the HVAC damper might have a longer life.

  • Do you maintain your AC regularly?

If you will not maintain your AC on regular basis then the life of HVAC dampers will decrease due to wear and tear.

If you will maintain your AC on regular basis then your HVAC dampers will last for longer. Therefore, we recommend you regularly maintain and service your air conditioner. Fix and repair all the problems to increase the life of your AC.

How do i know if my air conditioner damper is bad

If your air conditioner damper is gone bad then how can you identify it? What are the signs of a bad damper?

Well, HVAC dampers are responsible for regulating the airflow through a section of the duct. Dampers can either stop the air flowing through a duct or regulate it using the climate control system.

If you have a bad air conditioner damper then it will have poor and uncontrolled airflow. You will either get too much airflow or too little airflow. Another sign is that you may have very little airflow even if the ducts are closed.

Therefore, problems with the airflow are a sign that your HVAC dampers might be bad.

How much does it cost to replace ac damper

Several different factors can impact the total cost of replacing the damper of your air conditioner.

  • Cost of damper

How expensive or cheap is the price of a damper in your area? Which brand and quality of damper you will choose? Etc.

  • Cost of labor

What is the per hour cost of labor in your area? How much time and effort are required to replace the old damper with the new one.

Generally, it can cost you around $200 to $700 for replacing the dampers of your air conditioner.

Should hvac damper be open or closed

Whether you should keep the HVAC damper closed or open depends upon how you want to adjust the temperature of your house/room.

If it’s winter and the weather is chilling cold then you would like to keep your room heated and warm. Thus, you want a high temperature. In such a case, keeping the HVAC dampers closed will help you build up heat and stay warm.

If it’s summer and the weather is extremely hot then you will like to stay cool and calm. Thus, you will need a cool temperature. In such a case, keeping your HVAC dampers open will help the cool air to enter your home and keep you peaceful.

Therefore, the bottom line is that you should keep your HVAC dampers closed during winters and opened during summers.

How to know if ac damper is open

When you want to adjust the temperature of your house then it is very important to make sure that your AC damper is closed or open.

How can you find out if the damper of your AC is open?

Well, the fastest and simplest way is to go upstairs and place your hand over every single vent. It will easily help you find out which damper is closed and which is open.

Is air conditioner damper worth it

Yes, air conditioner dampers are worth it. There are two reasons for that:

  • Customize the temperature

Dampers allow you to customize the temperature of every single room without affecting the temperature of other rooms.

If you have a central air conditioning system and you want to have a different temperature in a particular roomwithout affecting the temperature of other rooms then using dampers is the best choice you can make.

Let’s suppose your parents don’t like too cold temperature in their room but all the other people in your house want cold temperature. You can use the AC damper to regulate the temperature of your parent’s room whereas the rest of the rooms will have the same cold temperature.

  • Energy saving

Central air conditioning systems cool all the rooms of your house. If you don’t need cooling in a particular room then you can simply stop the cooling in that room with the help of dampers. This way you’ll be able to save energy.

Are dampers bad for hvac

The purpose of dampers is to regulate the airflow and temperature in one room without affecting the temperatures of your other rooms.

Although dampers aren’t bad for your HVAC unit.But the way you use them has a significant impact.

If your AC unit is running and you have closed all the dampers in your house then the air will find no place to get out. This will put intense pressure on the HVAC system and inflict damage to it.

Therefore, you need to be careful of that.

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