Yes, you can close a damper, but whether it should be closed all the way depends entirely on the type of appliance and if there is an active fire.
You must open the damper fully before lighting a fire. This allows smoke and gases to escape through the chimney instead of coming back into the house. If the damper's closed, you risk carbon monoxide buildup, which can be dangerous. Use the handle or lever inside the fireplace to open the 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.
For a Hotter Fire
Fully open the damper to maximize airflow. It provides ample oxygen to the fire, resulting in a more intense and hotter burn. The damper must be fully open when lighting the fire.
An open damper can let rainwater enter your chimney, producing multiple problems. Moisture can harm both the damper itself and additional chimney components. It can also seep into your home's structure, causing moist patches, mold, and mildew growth, and even structural damage in some cases.
In winter, the position of your damper depends on what you are using.
If you are looking at a duct that is coming off the furnace and going straight up like it is going to the upstairs, and the wing is in the same direction as the duct, it is open. If the wing is in the opposite or vertical position to the ductwork, then the damper is closed.
One caution, though: Fireplaces with installed gas logs are required to have the damper open at all times. That's either because a pilot light is constantly burning under the logs or because the homeowner might forget to open the damper when he or she turns on the fire.
The worst firewood to burn falls into two categories: toxic and highly inefficient. You should never burn wood that produces dangerous chemical fumes or excessive smoke, nor wood that burns too quickly or spits hazardous sparks.
Some of the reasons a chimney damper won't close properly include shoddy installation, age-related damage, or heavy snow or ice affecting a top-sealing type.
No. The damper must be in the fully open position when using a wood-burning fireplace. Partially closing the flue (chimney) damper can cause smoke to spill into the room when burning wood, or cause carbon monoxide (CO) to come into the room when using gas logs.
The "7 Times Rule" for chimneys dictates that the cross-sectional area of a masonry chimney flue cannot exceed seven times the area of the appliance’s vent connector (draft hood outlet) to ensure proper drafting and prevent acidic condensation. If the chimney is too large, it must be relined to prevent damage from cooling gases.
Fire dampers are installed in these duct or ventilation openings. They close automatically upon detection of heat by a heat-responsive device (usually by the melting of a fusible link at 165°F [74°C]), blocking the opening and preventing the spread of fire into the adjoining compartment.
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.
Once golden and crusty on the outside, push a long knife through the middle. If the damper is cooked through, the knife will be clean when removed. Tip: Another way to know that your damper is ready is if it sounds hollow when tapped. Serve with your favourites spreads!
The "20-degree rule" in HVAC has two meanings: it refers to the physical limit of the air conditioner (how much it can cool the air) and a thermostat guideline (how much cooler your home should be than the outside temperature).
It is illegal to burn any wood that has been treated, painted, or glued, as well as poisonous plants and driftwood. Burning these materials releases toxic chemicals, heavy metals, and hazardous fumes into the air.
Properly cured, or "seasoned" firewood needs to be cut, split and stacked for a minimum of six months to be properly dried for this fall and winters fireplace needs.
The absolute hottest burning firewood in North America is Osage Orange (also known as hedge apple or bois d'arc). It produces up to 32.9 million BTUs per cord. Other premium, ultra-dense hardwoods like Black Locust and Hickory are tied for a close second, outputting around 26 to 30 million BTUs per cord.
But can I close my damper just a little so I lose less heat on my chimney? No, never do this. 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.
Buildings are divided into fire-resisting compartments using walls, floors and ceilings designed to resist fire for a set period, typically 30, 60 or 120 minutes. Fire dampers exist to ensure that ventilation systems do not undermine this compartmentation.
Here's an example to help illustrate this, with a fireplace with a Btu rating of 30,000: (30,000 x 1.59) / 100,000 = 0.47. That means it will cost about $0.47 per hour to run your fireplace. If you run your fireplace for 8 hours a night, it will cost $3.76 a day.
When the fireplace is in use, the damper (whether it's a throat damper just above the firebox or a top-mount damper at the top of the chimney) must be open. An open damper allows smoke to exit the chimney rather than backing up into the house.
A closed fireplace damper looks like a flat or slightly angled metal plate (cast iron or steel) that completely seals off the throat or top of the chimney flue. When closed, it blocks your line of sight, preventing you from looking up into the chimney.
A fully open damper allows maximum airflow, making the fire burn hotter and faster. If you want a slower burn or a fire that lasts longer, you can partially close the damper to reduce the oxygen supply. Just be careful not to close it too much because it can lead to poor combustion and smoke buildup.