When should I open my HVAC damper?

Author: Richmond Kerluke  |  Last update: Thursday, July 24, 2025

When Should I Open and Close My HVAC Dampers? In most houses, dampers on the upper level are opened in the summer and shut in the winter. In the winter, closing the dampers on your HVAC system to the upstairs allows for heat to rise naturally as it is distributed throughout the home.

Should my HVAC damper be open or closed?

Dampers do a much better job of stopping air flow than closing the register. That's because by the time the air reaches the end of the ductwork, it has no where to go but leak out. If you close the damper, any air leakage will not have enough velocity to travel the distance of the ductwork.

Should I open my damper all the way?

No you would never burn with the top mount damper closed. The damper should be fully open when burning. The top Mount damper is more to keep warm air in and cold air out when your not using the fireplace. You should be able to adjust the handle on the cable coming down the chimney so it closes all the way.

What position should my damper be in?

HVAC Damper Open Or Closed In Summer/Winter

In most homes, dampers going to the upstairs are open in the summer and closed in the winter. By closing the dampers to the upstairs in the winter, it allows for the heat to rise naturally after first being introduced into the lower levels of the home.

When should you adjust dampers?

Most people find that they need to adjust the airflow when the weather turns from cold to hot air. To determine if your air conditioning vents need to be adjusted seasonally, you will just need to monitor the ambient air temperature in each room of your home for two or three days.

UPSTAIRS IS HOT: Adjust Dampers For Heating Plus How to Tell if Dampers are Open or Closed

How should dampers be set in the summer?

In the summer, the lower level is naturally cooler, and most people report having hot rooms. In the summer, it's critical to open the dampers on the upper level and block as much air from entering the basement as possible.

Should damper be fully closed?

The damper to your fireplace must be completely open when a fire is burning. If you close the damper even slightly, you risk allowing smoke and other dangerous contaminants from the combustion process into the house. And remember, the most dangerous by-product of combustion is carbon monoxide.

Do you get more heat with a damper open or closed?

The handle to open and close the damper should be above the fireplace opening. To open it, slide it to the right. To create fires that produce more heat, open the damper as wide as possible when lighting a fire. A wide-open damper will increase the amount of air reaching the fire and improve combustion.

What is the best damper setting?

You could row every workout at the recommended damper setting of 3-5, no matter how short or long the workout, and no matter the intensity. But if you like to experiment, you can try lower or higher drag factors and see how it affects your performance and feel.

How far open should the damper be?

always fully open the damper. If you're burning wood, keep it fully open until all the burning embers are completely burned out. If it's a gas log set, turn off the flames before the closing the damper as far as possible.

When should you close your damper?

The damper is designed to be shut when the fireplace is not in use and can be easily opened when it is. It's common to forget to close the damper after a fire goes out, however, and that leaves a big hole through which heated or cooled air can escape the house.

Do I push or pull the damper to open?

To open a damper with a poker mechanism, center the poker through the formed slot which is hooked to the breast of the fireplace damper and push in a direct upward motion.

What happens if you don't open the damper?

You need to open the damper when you start a fire to allow for proper airflow and let the smoke out. A closed damper can restrict airflow and become a safety issue since smoke would fill your house.

Is it OK to leave damper open?

One common myth about chimneys is that leaving the damper open during the summer helps “air out” the chimney. However, the opposite of true. Leaving the damper open just fouls up the rest of your home, and does nothing to clean your chimney.

Does closing a damper increase heat?

By not creating an airtight seal, these dampers minimize the strain on the system. In summer, you can close the dampers downstairs so cooler air reaches upstairs rooms. But in winter, closing upstairs vents halfway allows heat to rise.

Are dampers worth it for HVAC?

The primary benefit of using an HVAC damper is that it helps to conserve energy by allowing you to restrict airflow in certain parts of your home where it isn't needed. By regulating the flow of air, you can better maintain desired temperatures and reduce the amount of energy used throughout your home.

What does increasing damper do?

Higher damper settings allow more air into the flywheel housing. The more air, the more work it takes to spin the flywheel against the air. More air also slows the flywheel down faster on the recovery, requiring more work to accelerate it on the next stroke or pull.

What level should I row on?

A “10” setting allows the most airflow and therefore the highest resistance. A “1” permits little airflow and minimizes resistance. Beginner rowers should start in the 3-5 range. Higher settings make for more strength-oriented workouts, which are more difficult to sustain and, therefore, yield less aerobic benefits.

What sets the damper position?

The damper position is set by the thermostat. The thermostat controls the temperature in the air-conditioning system by responding to changes in the temperature. If the thermostat senses that the temperature is too hot or cold, it sends a signal to the dampers, which adjust to let in more or less air.

Does closing the damper make the fire hotter?

Use the Damper to Control Heat

Depending on how far open or shut you have the damper, your fire will be smaller and cooler (and burn for longer), or larger and hotter (and burn more quickly). The damper is usually located at the bottom of the stove.

Should the damper be open or closed at night?

What do you do to put the fireplace to bed at night? If the fire is still producing heat, the damper has to be left open. And if the damper is open, the heat inside the house finds a fast exit to the outside.

Should vents be open or closed for more heat?

Open Vent: Open vents help maintain a consistent temperature throughout your home. This is particularly important if you have a multi-story house, as closing vents on one level can lead to uneven heating or cooling.

How to set dampers in summer?

Dampers are used to control which areas get more airflow. In the summer, you want more (cold) air going to the upper stories and less to the lower stories. This is due to the fact that warm air rises, and so the upper stories will naturally be warmer than the lower.

How far should I open my damper?

Open the fireplace damper all the way when starting a fire. Let the fire burn for a few minutes then adjust the damper so that it is partially closed (about half way) to see how it affects the fire. Monitor the fire and if it's still blazing, close the damper a little more (about two-thirds).

Is it OK to close HVAC dampers?

Excessive static pressure inside an HVAC system is never a good thing. Closing too many air supply dampers could put you in the static pressure “danger zone.” Instead, have a pro measure the static pressure to see if you can safely adjust your dampers. If you can't, consider one of the alternative solutions.

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