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Check Your HVAC Dampers

Are you experiencing issues with heating and cooling in a specific room or area in your home? You may have either too much airflow in a room, or none at all.

There might be an easy fix that you can do yourself before you call for service – and that’s checking the dampers in your HVAC system!

How Do I Know If I Have Dampers In My HVAC System?

First, you’ll want to make sure that you have a forced air system. It’s usually very easy to tell, since if you have a forced air system you will have air vents in each room.

You will want to look around the primary trunk line – the main ductwork coming from your furnace and indoor AC equipment. It can also be referred to as the “main supply trunk.” In more plain terms, go to where your equipment is located and check the duct pipes in that area. These are the lines that run throughout your home to the vents in your room.

If you have dampers, you will likely see a “lever” of sorts – see example above. This metal lever can be the same color as the ductwork, so bring a bright flashlight with you and hunt around carefully!

HVAC Damper Adjustment

In older homes, you may see a different style of damper that may look like a “clamp” on the ductwork with a screw.

How Do I Adjust The Dampers In My HVAC System?

Usually, it’s very simple and involves just moving the lever to the opposite position from what it is currently in. This will either open or close the damper, which will either allow the forced air to travel through that duct – or prevent the forced air from traveling through that duct. Based on where the damper is, you may be able to identify right away which room/vent it goes to. If you’re having trouble, give us a call.


HVAC Lever Damper


If your dampers are older or “non-standard,” you may need a tool such as a screwdriver to loosen the adjustment screw, move the lever, and re-tighten — but the end result should be the same.

If your damper is set incorrectly, making this adjustment can be a quick and easy fix if you’re experiencing heating and cooling issues in one room or area of the home.

What If I Don’t Have Dampers?

Many homes do not have dampers in their HVAC systems at all. If this is the case — and you’re experiencing heating/cooling issues in a specific room of the home — we’d recommend that you give us a call to set up a diagnosis visit. There could be many factors contributing to the problem, including:

  • Ductwork issues such as a leak (which would prevent heated or cooled air from reaching the room in question)
  • Issues with the blower motor
  • A blockage somewhere in the ducts, requiring a duct cleaning service

What If I Have A Zoned System?

If you have a zoned system, you may have electronically controlled dampers. If this is the case, your best option is to call us for service. These systems can be complex, and it’s best to leave this up to the professionals!

Ok. I’ve tried this and I’m still having a problem.

We recommend that you give us a call at 224-419-5324 or contact us online, and our dispatch team will help you schedule a service visit! Our professionally trained and field-seasoned techs will come out to your home and inspect your system to determine the underlying cause, and make recommendations for repair or replacement. We’ll also let you know if you need ductwork repair and what that would look like, if appropriate.

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