Can I partially close the damper?

Author: Dayton Satterfield III  |  Last update: Thursday, June 11, 2026

Controlling or Throttling the Damper After you open the damper and light the fireplace, wait a few minutes for the fire to build into a productive fire. Then, partially close the damper about one-third of the way. This will retain more heat inside your home, leaving plenty of room for the fumes to vent.

Should the 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.

Should the fireplace damper close all the way?

The damper should be kept closed when there is no fire or coals burning. Warm air from your home will not be lost up the chimney when the fireplace is not being used. Fully open the damper before your start a fire and keep it fully open until all embers and coals have burned out.

How long after a fire can you close the damper?

Do not close a fireplace damper until the fire is completely out.

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.

How to Open a Damper - 3 Types - Poker, Rotary, Double Pivot

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.

How to maximize heat from a fireplace?

Evenly distributing small pieces of wood throughout the fireplace will increase air circulation and speed up the burning of the wood. This creates a sustainable fire, but the wood burns faster. Placing large logs closer to the fireplace will keep the fire burning longer between refills, maximizing heat output per log.

How much to close a damper?

After you open the damper and light the fireplace, wait a few minutes for the fire to build into a productive fire. Then, partially close the damper about one-third of the way. This will retain more heat inside your home, leaving plenty of room for the fumes to vent.

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.

How do you air out a house after a fire?

Bring in fresh air

Air out your indoor spaces as much as possible by opening windows and doors. If you have minimal smoke smell/damage inside your home – and the area outside smells worse – don't take this step.

How much should the fireplace damper be open?

Open the fireplace damper all the way when starting a fire. 2. 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.

Can I close the damper with embers?

We don't recommend leaving the damper closed, because the fire can't vent through the fireplace very well, and the fire can't burn properly. Not only can leaving the damper closed affect the burning fire, but it can also allow carbon monoxide poisoning to enter the home.

How much heat is lost through an open chimney?

Warm air from your home naturally rises, and an open chimney provides an easy escape route. In fact, it's estimated that up to 30% of your home's heated air can be lost through an open chimney when the fire isn't in use.

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.

Can you close a damper all the way?

The damper is the part inside your flue that controls the airflow entering and exiting the tunnel. Should you close a damper all the way? Always fully close the damper when you are not using the fireplace. This will lower your energy bills and prevent leaf litter or pesky critters from invading your home.

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.

How to make a fireplace more efficient?

6 Tips to Make Your Fireplace Super-Efficient
  1. Burn Seasoned wood. Dry wood burns hotter and more efficiently than damp (unseasoned) wood. ...
  2. Chimney cleaning. ...
  3. Make sure your damper works correctly. ...
  4. Fix excess drafts inside your home. ...
  5. Convert an inefficient masonry fireplace.

What is the slowest burning firewood?

Hardwood burns the slowest, produces the most intense fires, and produces hot coals that remain hot long after a fire has gone out. When hardwoods are burned in good conditions for a fire, they produce very little smoke or unhealthy particulate matter.

Should I close the glass doors on my fireplace?

Keeping fireplace doors open results in a more lively fire but can lead to heat loss and safety concerns. Closing fireplace doors improves efficiency, enhances safety, and directs heat into the room. Oxygen is vital for a healthy fire, and closed doors draw air from outside to maintain an efficient burn.

How long does it take for a fire damper to close?

Actuator operated fire dampers are equipped as standard with a thermoelectric fuse, that activates the closing of the damper after the reaching or exceeding the ambient temperature of 72 °C. The actuator power circuit is interrupted and its spring closes the damper blade within 20 seconds.

How long to wait before closing damper?

How to Do It: Wait until all embers have extinguished and the fireplace is no longer warm to the touch. Closing the damper too soon can trap smoke and carbon monoxide inside your home, creating a dangerous situation. Safety Tip: Always double-check that the fire is completely out before closing the damper.

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.

Why can't I feel the heat from my fireplace?

Issues may arise from a variety of factors: creosote build up or other blockages in the chimney flue, insufficient ventilation, or negative air pressure within the home. These factors impact not only the heat of your fires, but also the safe usage of your fireplace system.

How to stop all the heat going up the chimney?

One easy and sustainable solution is to install a sheep's wool draught excluder. These come in both rectangular and circular shapes and in a range of sizes to fit any chimney. They're a kind of wool pad with a handle on one side so that they can be placed just inside the chimney.

How do I make my fireplace fire burn longer?

To make your fire burn for longer, reduce the airflow by partially closing the damper or adjusting the air vents. This helps regulate the oxygen supply to the fire, creating a slower and more controlled burn that can last for extended periods.

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