Dampers on Fireplaces: A Complete Guide to Installation and Use

Installing a damper on your fireplace is a relatively simple process, but it's crucial to get it right to ensure safe and efficient use.

A damper is typically installed in the flue of a fireplace, and its primary function is to control airflow and prevent heat from escaping. It's usually a metal or ceramic flap that can be opened or closed to regulate airflow.

To install a damper, you'll need to access the flue of your fireplace, which can be a bit of a challenge, especially if you have a masonry fireplace. However, with the right tools and a bit of patience, you can do it yourself.

The type of damper you need will depend on the type of fireplace you have, with masonry fireplaces typically requiring a more robust damper than prefabricated fireplaces.

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A damper's size and type matter when selecting one for your fireplace. Typically, a 6-inch or 8-inch damper is standard, but larger or smaller sizes may be necessary depending on your chimney's dimensions.

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There are two main types of dampers: throat dampers and top-sealing dampers. Throat dampers are more common and sit inside the chimney flue, while top-sealing dampers fit over the top of the chimney.

A throat damper's location inside the flue allows for easier installation and maintenance, but it can also create a gap for cold air to enter if not properly sealed.

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Chimney dampers are designed to withstand heat and come in various materials. Cast iron and stainless steel are the most common materials used to make dampers, with some cap dampers made from cast aluminum.

Cast iron or steel dampers are often used in masonry fireplaces and come with a worm gear mechanism that allows for easy opening and closing. A key is usually visible from the front of the fireplace, and turning it to the left opens the damper, while turning it to the right closes it.

Some dampers are made from ceramic materials, but this is less common.

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There are different types of dampers available, each designed for specific types of fireplaces.

Cast iron or steel dampers are commonly used in masonry fireplaces. They usually span the full width at the top of the firebox and are operated by a worm gear mechanism.

Lever-operated dampers are another type, often found in masonry fireplaces. They're operated by a simple lever mounted on the right inside wall of the fireplace.

ZC pivoting dampers are used in factory-built zero clearance fireplaces. The damper is a simple metal plate that pivots open when a lever is pushed or pulled.

Lock-top dampers are designed to seal the chimney at its top, rather than at the top of the firebox. They come in different sizes and shapes, but their function is the same as other dampers: to seal up the chimney.

Here are the different types of dampers:

Chimney dampers are designed to withstand heat, but not all materials are created equal. Cast iron is a common material used for dampers, as it can handle the high temperatures near the fire.

Some dampers are made from stainless steel, which is even more durable and resistant to heat.

Cast aluminum is used for cap dampers, which are farther away from the fire. This makes sense, as they don't need to withstand the same level of heat as other dampers.

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A damper's main function is regulating smoke and gases, and preventing outside air from entering the home when the fireplace isn't in use.

There are different types of dampers, including throat dampers and top-sealing dampers. Throat dampers are typically installed just above the firebox, while top-sealing dampers are installed at the top of the chimney.

A properly functioning damper can help prevent cold air from entering the home and warm air from escaping. This can make your home more energy efficient and weatherproof.

To adjust the damper for proper airflow, you can partially close it to slow down the burning of the fire. However, be careful not to close it all the way, as this can cause back puffing or smoke to flow into the room.

Here are some key differences between a damper and a primary air control:

In addition to regulating airflow, a damper can also help to prevent wildlife from entering the home through the chimney. This is especially important if you live in an area with a lot of wildlife, such as birds or squirrels.

It's also worth noting that a damper should be fully opened when a fire is going, and closed when the fire and coals are out and the fireplace is not in use. This will help to prevent cold air from entering the home and warm air from escaping.

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Always open the damper fully before lighting a fire, allowing smoke and gases to escape through the chimney instead of coming back into the house.

The fireplace damper is crucial for safety and efficiency, and you should check to make sure it's completely open before starting a fire.

You should close the chimney damper when the fire and coals are out and the fireplace is not in use, to prevent heated air from being pulled through the fireplace and lost up the chimney.

Each year, retail fireplace dealers get phone calls from customers asking why their furnace cycles on or why the living room cools down when they have a fire, and nine times out of ten, the fire has gone out and the damper has been left open.

Never close a fireplace damper while a fire is burning, as smoke will quickly back up and fill the room, posing severe health risks and potential property damage.

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Regular maintenance is essential to ensure the damper works and seals properly, and you should inspect the damper once a season for damage or wear and tear.

Some people may think they can get away with closing the damper partially, but this is not recommended as it can allow smoke and other contaminants into the house.

Here are some safety tips to keep in mind:

If your damper is not shutting or is missing, the fireplace can be safely used if it passes a chimney inspection.

If you notice a damper that doesn't seal tightly, it's probably time to call in a professional. Damper problems can be caused by a buildup of soot and creosote, which can affect the damper's ability to operate.

Moisture can also cause cast iron dampers to rust and deteriorate. This can happen over time, especially if your damper has been exposed to high temperatures.

Excessive heat buildup can warp the original shape of a damper, making it difficult to function properly. This is a common issue that can be caused by years of heating up to high temperatures.

If you find that your damper is missing or damaged, don't worry, there are options available. A certified chimney professional can inspect your entire fireplace system and recommend the best course of action.

Here are some common problems that homeowners experience with their chimney dampers:

Annual inspections by a certified chimney professional can help catch these issues before they become major problems. They will inspect your entire fireplace system, including the damper and chimney, and provide recommendations for repair or replacement.

If you're tired of a cold and drafty wood burning fireplace, there's a solution. The Lock Top II Chimney Damper With Cap is a perfect solution for this issue.

A traditional metal fireplace throat damper can be very leaky even when closed, but the Lock Top Chimper Damper offers a better alternative. This damper can save you money by reducing heat loss.

The US Fireplace Top Damper Plus is another option for sealing your chimney. It's a top mount style damper that prevents heat or air conditioning loss when the wood fireplace is not being used. Unlike traditional throat dampers, it doesn't leak.

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You can also consider the US Fireplace Top Damper, which provides an energy tight seal for any fireplace. It's made of stainless steel and aluminum, ensuring it won't rust.

Here are some common uses for dampers:

It's worth noting that gas burning fireplaces don't require dampers due to building code.

If you need to replace a chimney damper, you'll want to consider a replacement cable, like the 50-foot cable for chimney dampers.

A 50-foot cable is a standard length for replacing dampers, so you'll want to make sure you have enough to complete the job.

You can find replacement cables specifically designed for chimney dampers, such as the 50-foot cable mentioned earlier.

The Round Stainless Steel Kit is a top-notch option for restoration projects involving wood burning fireplaces. It's constructed from high-quality 316Ti stainless steel, which is built to withstand repeated chimney fires.

This heavy-duty Round Flue Damper is a game-changer for homeowners who want a reliable and safe way to control airflow in their chimney. It's spring-powered and designed to drop into place, making it easy to install.

The Round Stainless Steel Kit is a great choice for those who want a durable and long-lasting solution. It's not prone to melting like other dampers on the market, which is a major safety concern.

You might be wondering how much of a difference a good damper can make in your energy bills. The truth is, a masonry fireplace with traditional metal throat dampers can be responsible for around 8% of your total heating cost.

If you need to replace a chimney damper cable, you'll want to get the right length to fit your needs.

A 50-foot cable for chimney dampers is available, providing enough length to cover most installations.

This cable is specifically designed for use with dampers, ensuring a secure and reliable connection.

The Handle/Valve Extender is a game-changer for those hard-to-reach dampers.

The HEK Handgrip/Valve Extender Kit is a must-have for high chimney dampers.

This kit allows you to extend your reach by many extra inches, making it much easier to install or remove your Chimney Balloon.

The valve handle is also conveniently located near the valve mouth, making it a breeze to use.

The kit comes with a chain assembly, bracket, nail anchors, adhesive, and allen wrench.

Your house will quickly fill with smoke if you start a fire with a closed damper.

You should get into the habit of checking whether the damper is open or not before starting a fire for safety reasons.

To determine if the damper is open or not, you'll need to know the type of damper you have.

Before you light that first fire of the season, make sure to inspect your damper for damage. Over time, dampers can rust, warp, or get clogged with soot and creosote.

It's essential to check the damper once a season for damage or wear and tear. If it's difficult to open and close, call a chimney specialist to see if it can be repaired or if it needs to be replaced.

A little preparation now can save you from bigger problems later. This is especially true when it comes to fireplaces and chimneys, which require regular maintenance to ensure safe and efficient use.

Gas logs can be vented or unvented, and this affects how you use the damper. Vented gas logs require the damper to be wide open to operate safely.

Local codes and the type of gas logs you have will determine whether you need to open the damper for safety. Many vented gas log sets are designed to run continuously with the pilot light on, so it's easy to forget to open the damper before ignition.

Unvented gas logs, on the other hand, can be operated with the damper closed. They may add a bit of heat to the room, but they also add moisture, which can lead to odors and other issues.

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Before starting a fire with your gas logs, it's essential to check the controls to ensure the damper is in the correct position. Familiarize yourself with the chimney and its controls to make this process easier.

A closed damper can cause smoke to fill your house, which is not only unpleasant but also a serious safety risk. You risk damage to your home, belongings, and health.

If you're unsure about the damper's position in an unfamiliar house, perform a visual check after looking at the control position. This will help you avoid any potential hazards.

A closed throat damper will cause smoke to fill your house immediately when you start a fire.

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Gas logs require attention to safety and functionality.

Some gas log sets are vented, meaning the damper must be wide open to operate safely.

Local codes and the type of gas logs determine the damper's position.

A small C-clamp keeps the damper slightly ajar in vented gas log sets.

Unvented gas logs can be operated with the damper closed.

Operating unvented gas logs for too long can add considerable moisture to the room.

Some unvented equipment may cause odors in the home.

Manufacturers often recommend operating unvented gas logs for only a few hours.

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If you're looking to improve the efficiency of your damper, consider installing a damper lock to prevent accidental openings, which can lead to heat loss and reduced chimney performance.

The type of damper you choose depends on the type of chimney you have, with throat dampers suitable for masonry chimneys and top-sealing dampers ideal for prefabricated chimneys.

Installing a new damper can be a DIY-friendly project, but it's essential to ensure proper fit and sealing to maintain a safe and efficient chimney system.

For optimal performance, maintain your damper by cleaning it regularly to prevent creosote buildup and ensure smooth operation.

To install a top mount chimney damper, you may need a Flue Extension if there's no existing flue tile extending from the chimney top or the flue tile is too short.

The extension pieces are 4 inches tall and easily bolt to the flue extension with tapcon screws, which you'll need to purchase separately.

You'll need to purchase tapcon screws separately to secure the Flue Extension to the damper.

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