What if your gas log fireplace sucked money out of your wallet?

What if your gas log fireplace sucked money out of your wallet?

Fireplace Sucks amin

What would you do if the directions of your vented gas log fireplace said: “Step 4: Turn on the gas and light log set with a flaming $10 bill”. No matter what you tried, you couldn’t get the gas log to light unless you burned a $10 bill and put it to the logs to light it. I think you would be tempted to write the manufacturer about this issue, or talk to the store you bought it from, or maybe just not use it!

The inefficiency of a vented gas log fireplace

In a way, this is what it is like to use a vented gas log fireplace. You get little to no usable heat from the device, you consume fuel in it, its use/or non-use sucks heat from your home, but it sure makes a nice flickery flame. Is it worth it?

There are some key elements that are dead wrong with vented gas log kits. The primary issue is the damper use with these kits. Most state building codes say if a vented gas log is installed in a fireplace the metal damper has to be locked open or removed. The reason for this particular code is so that people don’t turn on their vented gas log and forget to open the damper and therefore asphyxiate the inhabitants of the home. The reality of this code is the homeowner has to live with a sizable hole in their homes energy envelope that is releasing energy 24/7.

Vented gas logs do not produce usable heat

The vented gas logs combustion process does little to produce usable heat to the living area. Much like a wood burning fireplace, the vented gas log wastes heat in many ways. The combustion process grabs already heated air from your home and burns the oxygen and combustible gasses in it. The heat that is created in this combustion quickly rises and grabs more heated inside air and tosses it up the chimney. You can restrict the amount of inside air that the fireplace has access to by installing glass doors, but this will also severely limit the amount of radiant heat that fireplace can cast forward into your living space. This radiant heat is the heat you feel on your skin in front of the fireplace and is the only usable heat that the fireplace will produce since the combustion heat is pouring out the top of the chimney. In the meantime, the home is drawing in cold outside air from other places (i.e. windows, light sockets, doors, etc) to replace the air that is escaping the home through the chimney. This is referred to as the “stack effect”.

How much money and heat is lost?

Most vented gas log operate at a consumption of .5 to 1 Therm per hour. In January of 2008 one Therm of Natural Gas cost me $1.57. So if you burn your vented gas log for 3 hours you wasted $4.71 worth of fossil fuels, and have no heat to show for it. With that same amount of natural gas you could have heated a 1200 sq ft home with a 95% efficient power vent furnace all day long.

Vented gas logs are good for ambiance

The flickery yellow flame that is produced by a vented gas log is a very realistic looking flame, but it is a low temperature flame and therefore tends to burn “dirty” and outputs soot and other pollutants. If you have a vented gas log fireplace or are considering having your wood fireplace fitted for one. Consider first the cost and environmental ramifications of using it.

What is better a vented-gas log or a vent-free gas log fireplace?

What is better a vented-gas log or a vent-free gas log fireplace?

Gas log

Q: Jason – I have an old vented gas log that is crumbling and needs to be replaced. What is better to replace it with, a vented gas log or a vent-less gas log?-NW

A: NW- If you go with a vented gas log install you will certainly have to commit yourself to having the chimney damper removed or clipped or disabled in the open position according to current code for vented fireplace install. This means you will have a gaping hole to the outside
all the time. Many gas log owners are surprised to find that their fireplace flue damper has already been disabled when their original gas log was installed. The building fireplace code that states to disable the damper, is often an adequate enough reason for a homeowner not to go with any vented variety gas log.

In the vent-less model, you do get the benefit of retaining all of the heat if you keep the damper closed, but any of the CO, CO2, Nitrogen or moisture that it puts out will enter your living area as well. In the winter when your home is closed up you really want to minimize the extra pollutants you introduce to your already recycled inside air. This is not just with the fireplace, this goes for candles, sprays, paints and other pollutants. You obviously can’t avoid these items all-together, but do you want to introduce new contributors like a vent-free fireplace?

From our conversation on the phone, I am sure you have your heart set on a vented gas log, and you were just looking for brand-name references from me. But please take into account other options like electric fireplace inserts if you are looking for fireplace ambiance, or maybe even a candelabra with candles burned with the damper open as other suitable ambiance option that won’t cost you in heat loss. – Jason

Ventless gas logs that have a chimney…this is not normal.

Ventless gas logs that have a chimney…this is not normal.

Log wall

Q: Jason, I live in Tennessee, in a restored log home from the very early 1800s. I have a number of ventless logs inside of chimneys (which were originally wood burning.) We use our ventless logs during the winter to heat the rooms we’re in. (The house is 6000 square feet, and keeping the whole thing climate controlled seems wasteful, considering how poor logs are as insulators…) I want to figure out some way to keep more of the heat from the ventless logs in. Is the right thing to get one of your Chimney Balloons, some sort of heat reflector, a blower fan, or to stop being a cheapskate and spend the 700 a month it takes to heat the whole house if we simply do things “the normal way” with the central H/AC. – ER

A: Dear ER, Thank you for your interest in the Chimney Balloon. In order to answer your question well I think i need to clarify with you that you do in fact have vent free gas logs. If you have vent-free gas logs you would have no chimney at all in the fireplace. The vent free variety of fireplace is usually just a firebox in the wall with a heat disapator on the top of the fire box. If this is in fact what you have, then you have no need for a Chimney Balloon because you have no chimney. If you have a vented gas log then you do have a chimney in your fireplace and it is likely that the damper has been clipped open or is otherwise disabled due to current code regarding gas logs. In this case a Chimney Balloon will help you quite a bit. When a vented gas fireplace is not in use, its open damper will suck the heat right out of the room due to the air stack effect in your home, especially in historacle log construction like your home. As far as heating your home goes. Right now it sounds like you are practicing zone heating. This can be very effective way of cost savings in a home your size (6000 square feet). I hate to say this…but $700 per month is actually a resonable amount to pay in the winter months to heat this size of area with a traditional HVAC system. If there are not many of you living in your home you may find zone heating is the way to go. I am for it as long as it is done safely and makes your home as usable as it can be for your needs. I would encourage you to have an energy audit of your home (if you havent already) as a trained professional in insulation would be able to direct you to even greater savings, Jason

Q: Thanks for the reply. Here is where it gets weird. In the 6 fireplaces in my home, there *used* to be standard issue wood fires. Then they were replaced by vented gas logs in the 70s. In the very late 90s early 2ks, they replaced all of the vented logs with *ventless* logs. So I have 6 fireplaces with ventless logs in my house 🙂 Actual fireplaces, with chimneys. So, given *that*, what do you think is the right “plan A”? 🙂 Thanks! – ER

A: OK, well that clears things up a bit. Since you do have chimneys over these “ventless” gas logs then you can use a Chimney Balloon to plug these fireplace chimneys. The key is that you have to remove the Chimney Balloon from the chimney before you light that particular fireplace. This is particularly important to note if you are used to just firing up your gas logs without opening a damper. A Chimney Balloon is deigned to burst if you light a fire under it, and it doesnt matter if it is a vented or vent free fire. You have a unique situation here, but with a home that is 200 years old I bet you have a lot of unique situations with your home. Im sure it has a lot of character and has had many owners over it life and each owner has made interesting changes im sure. If I can be of further assistance please let me know – Jason

7″ Chimney flue with a swivel damper on a prefab fireplace. Will a 9×9 Chimney Balloon work on this?

7″ Chimney flue with a swivel damper on a prefab fireplace. Will a 9×9 Chimney Balloon work on this?

Fireplace damper swivel

Q: Jason, My fireplace has a small flue that is 7.5 inches in diameter. The type of fireplace damper I have is a small swivel type of damper. The damper is a round plate with a metal rod handle that goes through the middle of the round plate. See photo taken from inside the fireplace firebox looking up at the damper. Can I use a 9×9 Chimney Balloon on this chimney flue? – DC

A: Dear DC, Thank you for sending the photo of the swivel fireplace damper in your fireplace. A picture is worth a thousand words when it comes to describing fireplace dampers.

I would guess you have a gas log fireplace considering I think I see a clip on your damper holding it open. Often these clips are put on dampers according to building codes that dictate that a fireplace with a gas log fireplace unit must have the damper disabled or clipped open if they have a vented gas log. This code was written so that a family will not be asphyxiated with Carbon Monoxide if someone turns on the gas log without opening the damper first. The unfortunate thing is having your damper open all the time lets in a lot of cold air and lets out a lot of expensive home heat.

A Chimney Balloon can be used in this flue and I would recommend a 9×9 Chimney Balloon with an HEK handle extender. When you insert the 9×9 make sure you DO NOT pre-inflate it at all. Simply attach the handle extender to the handle before installation, so that you will have plenty of reach to get the Chimney Balloon past the swivel damper and  into a clear spot in the flue. Then slide the Chimney Balloon past the open damper and inflate it in place once you have it in the flue.

Since the 9×9 is slightly over-sized for this 7.5″ flue. If you start overinflating the Chimney Balloon you will notice that it will tend to want to tilt or tip sideways in the flue. If this starts to happen, simply remove a little air from the Chimney Balloon and coax it back down into horizontal position by pulling lightly on the handle valve. Let me know if you have any other questions. – Jason