# 4: I Have a Round Drop-down Trapdoor Style Damper. How do I Plug the Round Flue Pipe?

by blogediter | Aug 21, 2017 | Chimney Plugs, Fireplaces

# 4: I Have a Round Drop-down Trapdoor Style Damper. How do I Plug the Round Flue Pipe?

4-1 Open Flue Pipe above a Round Side-Hinged Damper

4-2 Closed Round Trap-door Side-Hinged Damper

4-3 9×9 Chimney Balloon installed in a Majestic Fireplace

Fireplace #4: Round Trapdoor Side-Hinged Damper Covering a Round Flue

This is the easiest of all the fireplaces to plug. The damper drops out of the way, and you get a clear shot at the round chimney flue. These sheet metal dampers are often fitted on Majestic or Superior brand zero-clearance pre-fabricated fireplaces. These were popular in the 70’s and early 80’s, and it is hard to get damper parts for them anymore. The sheet metal doors often warp, then the asbestos ring falls off the edge of the door. At that point they drop open on their own.

Wood Burning Fireplace Users:

Open the damper and make a diameter measurement of the hole just above the damper (image 4-1), then buy a Flueblocker that will fit in that hole. Or buy one that is a bit big for the hole, since you can then trim it down to fit with a sharp pair of scissors. Here are some examples:

Example 1: You measure 8” diameter = You buy a 9” Round Flueblocker

Example 2: You measure 9” diameter = You buy a 9” Round Flueblocker

Example 3: You measure a 11” diameter = You buy a 12” Round Flueblocker

Flueblockers are physically a little bit larger than their labeled size. This is so they can press in to fit and hold in place by pressure tension. When yours arrives you just press it right into place into the round chimney flue. It is up to you if you want to close the damper below the plug.

IMPORTANT! ESPECIALLY FOR FORGETFUL PEOPLE!:
If you close the damper below the Flueblocker, mark the fireplace VERY CLEARLY that the chimney is plugged. It is easy to forget about the Flueblocker up above the damper. You MUST open the damper AND remove the Flueblocker to use the fireplace.

Gas Log Users: If you have a gas log set in this fireplace, you have a decision to make.

Here are your two options:

You can turn off the gas line to this fireplace and put in a small 9×9 or 12×12 Chimney Balloon just above the damper. This way if you have a house guest that fires up the gas logs without asking, he won’t back up exhaust fumes into the house. The Chimney Balloon will burst and fall out since it is designed to do that. The downside to this, is the Chimney Balloon is an inflatable and not as durable as a Flueblocker.
You can turn off the gas line and remove or permanently disable the gas log set and then put in a Flueblocker. Do NOT light a fire under a Flueblocker. If you do light a fire under a Flueblocker fumes backup into the house and bad things happen…enough said.

Gas logs are a separate conversation. We also have an article on how gas logs can poison you or pick your pocket over time.

Are your gas logs picking your pocket, or are they just slowly poisoning you?

by blogediter | Aug 21, 2017 | Chimney Problems, Gas Logs

If you have been a reading my blogs you have probably gathered that I am not a big fan of retrofit gas logs. I don’t like vented or vent free gas logs, but it is for two different reasons:

Vented Gas Logs:

These are usually retrofitted into wood burning fireplaces. They are sold as an easier way to enjoy your fireplace, without the inconvenience of wood. To a degree they deliver on that promise, but there is more that they deliver.

When you install a gas log you must remove the damper or have it clipped open all the time. This is a bad deal for obvious reasons. This means you have a big hole in your home all the time, and you cant close it. It doesn’t matter if your fireplace is on or not that flue has to remain open and that allows for outside air to come in.
Most of the heat that is generated by the gas logs burning goes right up the flue. Unless you have a special kind of heat exchanger in your fireplace, that gas you are burning is throwing its heat right up the flue with the fumes. All you will get is some paltry radiant heat.
Older gas logs have pilot lights. They are the drippy faucets of the gas world. 24/7 you are trickling fuel down the drain.

Vent-Free Gas Logs:

I could go on and on about vent free gas logs. I really do not like these things. You are burning gas and venting all the heat and fumes into the home. This is great for heating, but what about air quality?

Vent-less gas log manufacturers swear by their newer products and say they are safe and do not elevate CO or CO2 levels. They say they even build in CO sensors that will shut the vent free heating device off if it malfunctions and causes a CO backup.

However, The University of IL (Urbana/Champagne) in 2008 introduced results of a study they conducted on 30 homes over a 3 years period to see how vent free gas appliances do effect the homes air quality. The complete study is available on-line, but it is a bit long winded, so I will give you a brief summary of what I found most interesting about it.

NO2 is the gas most likely to exceed acceptable levels when operating a vent free device.
The safety shutoff sensor on vent free units does not sense for NO2 levels.
CO occasionally exceeded the 8hr maximum in tests where they was a long continuous run time or in a tightly enclosed space.
The EPA says “Avoid installing un-vented (or “vent-free”) space or water heating appliances“

Now we all know that Carbon Monoxide (CO) is not something we want in our homes but (NO2) Nitrogen Dioxide was new to me so I had to look up the side effects. Quite frankly, I found the side effects to be less than desirable as well.

#3: I Have a Round Butterfly Damper with a Handle Attached. How Do I Plug the Round Chimney?

by blogediter | Aug 21, 2017 | Fireplaces

#3: I Have a Round Butterfly Damper with a Handle Attached. How Do I Plug the Round Chimney?How Do I Plug the Flue?

3-1 Open Round Butterfly Damper with Handle

3-2 Closed Round Damper with Handle

above the zero clearance fireplace damper

3-3 Flueblocker above Round Damper

Fireplace #3: Butterfly Damper in a Round Chimney with a Handle on the Face of the Damper

OK, so you have a butterfly damper with a hinged handle attached to it. Sometimes these are inset into the chimney a few inches (image 3-2). Sometimes they are right at the bottom of the chimney, and the chimney widens out to the firebox immediately below the damper (image 3-1). These sheet metal butterfly dampers pivot in the middle like a carburetor choke, and are often in bad shape, rusty and warped. After-all they are just made of sheet metal, and they are in a caustic and heated environment.

Wood Burning Fireplace Users:

Option 1: If you have space below your damper.
If you are lucky enough to have a small 1”or 2” vertical bit of chimney pipe sticking down below the closed damper before the pipe opens to the firebox (image 3-2). This is the perfect spot for a Round Flueblocker. You can tuck the Flueblocker against the face of the damper. But you will have to cut a slit in the edge of the wool pad for the damper handle to come down through.

Just make a diameter measurement of the hole below the damper (image 3-2), then buy a Flueblocker that will fit in that hole. Or buy one that is a bit big for the hole, since you can then trim it down to fit with a sharp pair of scissors. Here are some examples:

Example 1: You measure 8” diameter = You buy a 9” Round Flueblocker

Example 2: You measure 9” diameter = You buy a 9” Round Flueblocker

Example 3: You measure a 11” diameter = You buy a 12” Round Flueblocker.

Note: Flueblockers are physically a little bit larger than their labeled size. This is so they can press in to fit and hold in place by pressure tension.

Option 2: If you do not have space below your damper and it immediately opens to the firebox.

If there is no room below the damper (image 3-1), you will have to go with a Flueblocker ABOVE the damper (image 3-3) The wool pad is semi-rigid, so getting it up past the damper can take some pivoting and maneuvering. You may want an extra 6″ handle extender to make your handle longer.

Gas Log Users: If you have a gas log set in this fireplace, you have a decision to make.

Here are your two options:

You can turn off the gas line to this fireplace and put in a small 9×9 or 12×12 Chimney Balloon just above the damper. This way if a house guest come over and fires up the gas logs without asking, he won’t back up exhaust fumes into the house. The Chimney Balloon will burst and fall out, since it is designed to do that. The downside to this, is the Chimney Balloon is an inflatable and not as durable as a Flueblocker.
You can turn off the gas line and remove or fully disable the gas log set and then put in a Flueblocker. The Flueblocker does not burn away if you light a fire under it. If you do light a fire under a Flueblocker fumes will back up into the house. DO NOT do that!

#2: I Have a Circular Center Pivot Damper with No Handle. How Do I Plug the Round Flue Pipe?

by blogediter | Aug 18, 2017 | Fireplaces

#2: I Have a Circular Center Pivot Damper with No Handle. How Do I Plug the Round Flue Pipe?

2-1 Round butterfly damper

2-3 Where to Measure

round Flueblocker chimney plug installed

2-4 Flueblocker above the damper

round Flueblocker installed below the fireplace damper

2-5 Installed Below the Damper

Fireplace #2: Butterfly Damper with External Handle

The good news about this application is there is no damper hardware to fight with around the damper door. The damper handle is usually on the outside lintel face of the fireplace. Sometimes those handles don’t even work, because they get disconnected or rot out. But that doesn’t matter, because we don’t need them anyway!

Wood Burning Fireplace Users: Believe it or not, this application makes you very lucky. You will notice that there is a small 1”or 2” vertical bit of chimney pipe sticking down below the closed damper before the pipe opens to the firebox. This is the perfect spot to install a Round Flueblocker below the damper door (image 2-5). Or you can install the round Flueblocker above the damper (image 2-4).

Just make a diameter measurement of the hole below the damper (image 2-3), then buy a Flueblocker that will fit in that hole. Or buy one that is a bit big for the hole, since you can then trim it down to fit with a sharp pair of scissors. Here are some examples:
Example 1: You measure 8” diameter = You buy a 9” Round Flueblocker
Example 2: You measure 9” diameter = You buy a 9” Round Flueblocker
Example 3: You measure a 11” diameter = You buy a 12” Round Flu eblocker.

Note: Flueblockers are physically a little bit larger than their labeled size. This is so they can press in to fit and hold in place by pressure tension.

Gas Log Users: If you have a gas log in this fireplace, you have a decision to make. Here are your two options:

Option 1) You can turn off the gas line to this fireplace and put in a small 9×9 or 12×12 Chimney Balloon just above the damper. This way if someone fires up the gas logs without asking, they won’t back up exhaust fumes into the house. The Chimney Balloon will burst and fall out, since it is designed to sacrifice itself if introduced to flame. The downside to this, is the Chimney Balloon is an inflatable and not as durable as a Flueblocker so it will wear out after time. Also, you will have to install the Chimney Balloon above the open damper.

Option 2) You can turn off the gas line and remove or disable the gas log set and then put in a Flueblocker. The Flueblocker does not burn off if you light a fire under it. If you do light a fire under a Flueblocker fumes will back up into the house. So DO NOT light a fire under it.

My fireplace chimney damper is closed…so why do I still get a cold draft in the winter?

by blogediter | Aug 9, 2017 | Chimney Problems

Why do Dampers Leak Cold Air Even When They Are Closed?

Fireplace dampers are a 300+ year old invention. They are not much different today than they were 300 years ago. Here are 6 reasons dampers leak cold air:

Dampers and their frames are made of cast iron or sheet metal, so even a brand new damper that has never been used is leaky. The metal on metal contact points do not close perfectly, and you cannot have weather stripping on a damper door or it will burn off when you use the fireplace.
Dampers are heated unevenly with an open flame on a regular basis. This is a recipe for metal warping.
Dampers conduct heat and cold because of their solid metal construction. There is no insulation or R-value to a damper door.
Dampers get coated with creosote and soot. This coating tends to build up and cause a crust that further foils the metal on metal contact points. This crust can be removed with some scrubbing, but even chimney sweeps rarely spend time cleaning the damper itself. They just scrub the flue and smoke chamber.
The hinges on a damper are crude mechanical devices usually consisting of two interlocking fingers or just a pivot point. They are not continuous like a piano hinge. If you push on the hinge side of a damper door, you will see there is not much holding it together.
If you have a vented gas log that was professionally installed, the damper was blocked open or removed. According to code, when a gas log is installed the damper must be locked in a fully open position. This causes an enormous amount of heat loss.

As you can see, dampers are poorly designed to serve as a dam to hold back your interior heated air and to keep cold outside air from seeping in. Using a product like a Flueblocker, a Chimella or a Chimney Balloon in your dormant fireplace can go a long way to stop heat loss, make your home less drafty, and save money on heating and A/C bills.