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Letters From Vent-Free Gas Fireplace Owners
Page 1 - Letters 1-25

Page 1 (Letters 1-25)     Page 2 (Letters 26 - 50)    Page 3 (Letters 51 - 75)    Page 4 (Letters 76 - 100)    Page 5 (Letters 101+)

Sweepy If you're considering a vent-free (aka ventless, unvented or room vented) gas stove or fireplace, you should first read these letters, excerpts and E-mail postings written by unhappy vent-free owners. We've corrected spelling and grammar where necessary, and edited out some of the harsher language from the original text.

# 1: Serious ongoing health problems

My Name is Kim, I am trying desperately to locate other people who have suffered the long term effects of CO. My Family of four was poisoned for over two years, before we found out why we were all so sick. My five year old daughter was having many illnesses, eventually led to seizures. This all stemmed from a ventless gas fireplace we installed in our basement. Three months after it was installed my daughter had her first seizure. Husband began having severe headaches, trembling, memory loss, and numerous other ailments. Neurologists diagnosed daughter as epileptic!!!!! They now know they were wrong.

This began in January 1995. Husband still on oxygen every day, and medication, and extreme memory loss, and other problems. Daughter is having no more seizures, and last EEG done three months after gas shut off, was normal. First normal EEG in two years. We have been through it all!!! If anyone knows about CO, it's me and family. I have found a support group based in the United Kingdom that is helping us deal with this mess. And we are in search of other people who need our help. We are also trying to find a way to inform the public about this silent killer. Would you be able to help us in any way? Your concern could save a life. We have had a forensic scientist in our home doing tests on fireplace, and the final result was determined that you cannot put a combustible gas in an airtight home and not vent it. I have done much research on this situation and talked to toxologists, chemists, and other specialists, and not one of them can believe we are still alive, they are all behind us all the way. I'll be waiting to hear from you.


#2: Headaches, dizziness, unacceptable CO levels

We are a young couple with four children and live in a small community in Ohio. In 1996, we built a new home and moved in in late October. In November, we decided to try out our new vent free gas fireplace. Neither myself nor my husband are familiar with gas appliances, so we called [the owner of the retail shop where we bought the unit]. He had what he called a startup package for around $40. We were surprised at the charge since nothing was mentioned at the time of the sale, however we decided it would be best to know how to use it properly.

We asked [our retailer] about using a CO detector. He told us they really aren't necessary because the unit has a built in sensor that will shut itself off if the level gets too high. He also told us to let the unit burn for 4 to 5 hours to get the initial smell and burn off from the logs. We did this, but still noticed an odor even after 10-12 hours. We called [our retailer] again and were told to burn the unit for 100 hours. This seemed extremely long, but we did this over a series of 2 months.

In early January, we were still experiencing the odor and also seemed to notice a listlessness in our children, dizziness and sometimes headaches, while running the unit. At this time we still did not have a CO detector, so we have no idea how high the reading got at this point.

We finally decided to go out and buy a CO detector. Within half an hour of turning the unit on the warning alarm sounded. We called [our retailer] again and now he says that these detectors warn you way before there is a problem, so he still says we do not have a problem. We decided to buy another one and have one on the first and second floors. The upstairs would alarm within half an hour and the downstairs within 2-1/2 hours.

Again, we contacted [our retailer] and he told us the CO detectors we bought are too sensitive and to call [the manufacturer], to see what they recommend. They recommended a different brand with a digital display. So, we go out and buy our third CO detector. We now have two different brands of CO detectors in a loft area overlooking our great room. The great room measures 17x20 and has a 17 foot cathedral ceiling and this is where the vent free fireplace is located. The great room is also open to a kitchen/dining room and a 2-story entrance. So, it is a very roomy and open area. The following is an example of one days CO level readings:

  Time          Reading                Description


 7:50 am           0                Turned fireplace on

 8:05 am           7

 8:20 am           9             Upstairs CO detector alarm

 8:45 am          11

 9:40 am          13

10:15 am          14            Downstairs CO detector alarm

10:50 am          15

11:20 am          16

12:00 pm          17

12:30 pm          18

 1:20 pm          19

 2:00 pm          21                 Noticed dizziness

 2:20 pm          22

 2:45 pm          23          Headache starting - turned unit off

It took until 8:00 am next morning to get the detector reading below 10. These levels are not considered very high, but being exposed to these on a daily or every other day basis which we were in trying to get this 100 hours of burning time in, may become harmful, especially for our young children.

On another day of recording the readings, we got the following results:

  Time          Reading                 Description


10:00 am           0                Turned fireplace on

11:05 am          10

11:45 am          12

12:25 pm          14

 2:00 pm          20                Turned fireplace off

We called the fire department out and they felt we had a problem and should call the gas company. The gas company came out and they too felt we had a problem. Their representative told us any reading over 10 is unacceptable in a residential home. He also told us he was "red flagging" the unit, which he explained to mean that he had checked out all other possible sources of CO and determined the cause to be the vent free gas fireplace. This would let the gas company off the hook if something would happen to any of us.

Throughout this whole process we had over 30 phone calls to [the manufacturer] and [our retailer]. [Our retailer] was not willing to do anything except tell us to talk to the manufacturer. [The manufacturer] did try replacing the logs, they tried replacing the whole guts of the unit and the logs. The old unit was then to be sent back for testing. [The manufacturer] instructed [our retailer] to install the new burner and logs and return the old unit. I checked on the results of this and every time I was told that they had not received the unit from [our retailer]. They also tried new brick panels too. We still got the same results and every time they sent something new we had to go through the initial burn off process again.

Finally, after one year of frustration, [the manufacturer] suggested we try something new called a catalytic converter unit. They were going to send out technicians to check out the other unit and install this new catalytic converter unit. Well, here's another problem. We have the old unit enclosed in a brick front that goes all of 17' in height. I do not want to have to go through the expense and the mess of having the old one cut out and then the new one put in and still have the possibility of having problems because it would still be an unvented unit. We have done too much research in the meantime and know that we want nothing but a vented unit that has a vertical pipe running all the way up and through the roof. We only wish we knew all we do now before we started building. We are going to go through the expense and the mess and have this unit replaced, but we want nothing to do with any gas appliance that is unvented.

We have since this time talked to several people in fireplace sales and gas appliance installation and none of them are recommending the vent free units. We sure would not recommend one. We only hope that this information may persuade a person who is thinking of buying a vent free unit. Please think twice about it because we have also had moisture problems as well. Which is a totally different story.


#3: Soot all over the house

Hello, Found your webpage..and was so thrilled..have some questions. We purchased a vent free fireplace from a local distributor 2 yrs ago, and it has been nothing but a nightmare...soot, soot and more soot. I have been told it is the fact that it is vent free, or it is [the manufacturer]...whatever...they have not been able to fix the problem. So we have a beautiful fireplace I won't use, because it ruins the walls, curtains, etc. We have decided the only solution to our problem is to go with a vented fireplace, but will not buy from the same folks, and are very skeptical about buying thru a place like Lowes, etc. This can be a costly addition, and we don't want to have to go thru this repeatedly. Our source of fuel is propane..we also use this with our furnace. We have decided we'd better go to a vented fireplace, so am looking for suggestions. The fireplace we have now says max. 22, 000 btu, if that will help with size, etc. I would appreciate your assistance.
Thank You.



#4: Massive condensation damage

Despite a science background, I failed to consider the water production from burning propane when I left the (installed by builder) vent free wall gas heater on (low) in a mountain cabin during winter months to thwart freezing and supplement electric units. Well the pipes didn't freeze, but all windows had enormous ice deposits along their base and sides from the thaw/drip/freeze of condensed combustion water. This damaged drywall around the windows, cracked a large picture window (several hundred $ repair), and required me to strip and refinish water-damaged sills.

Even worse, the moisture condensed on the underside of the (poorly designed) sheet metal roof, whence it melted in spring to anoint the upstairs ceilings and floors with dripping drywall coatings and stains. This led to the belated recognition of the need for roof rebuilding (couple kilobucks) to help prevent future condensation, and the epiphany that non-vented gas heaters are bad for the house's health even if acceptable for the occupants'.

While pleased with myself for tracing the problem to the heater (I calculated how much water would be produced by the amount of propane consumed that winter while laying awake worrying about the demise of the house), I sure wish someone had educated me about the hazards beforehand.
Frank Symington


#5: Odor, dizziness

The only thing we do not like is that we feel very sick when using [a popular vent free model] even after letting the initial use take place. We're sure we let the initial odors and factory smells burn off, but it still has a dizzying effect on us. The dealer didn't help us much after we told them. I think we'll try and contact someone at the company to see if we can trade it in for a vented unit.
Posted at


#6: Wish they had bought a vented stove

[A popular vent free model] needs to be in a house with lots of air holes. If fumes bother you. I sort of wish I had paid a little more and got a vented stove. My house is a little too tight or small for a vent free one.
Posted at


#7: Hearth product retailer has removed over 200 vent-frees

I can't believe ventless products are still on the market. My company has removed over 200 vent free products now and replaced them with direct vents.The problem with this vent free issue is it's going to hurt the whole industry.When people come into our showrooms with problems, they don't say "my vent free product caused the problem" they say "my gas logs or my gas fireplace caused the problem". This is an area that we'd better start looking at as a industry.
Perry Bumpers


#8: Hearth product manufacturer refuses to offer "lung vented" products

I ran across your site yesterday when searching under "vent free". What a refreshing breath of fresh air to find a dealer who "gets it" when it comes to lung vented products! As you know, we (Heat-N-Glo, Heatilator and Aladdin) will not manufacture room vented products for the very reasons detailed on your website.
Tim Rethlake
Vice President, Business Development
Hearth Technologies
[email protected]


#9: Soot damage

Just thought you would like to know that I am currently the unhappy owner of a vent free fireplace that has sooted up my entire house. I just completed building the house this past spring, and heated it with the ventless almost exclusively this past winter after receiving a $600 electric bill after heating with my furnace for one month. Initially, the ventless fireplace seemed like a godsend.

After a couple of months, however, we noticed that the ceiling edges were beginning to collect soot. Shortly thereafter, all of the ceiling joists, wall studs, and drywall nails began showing up due to soot highlighting. We are now working with our insurance company to determine whether the cause is moisture in the gas or some failure in the ventless fireplace system. Regardless of the cause, all the walls and ceilings in our new home now looks black and dingy. Insurance will pay to have them washed and repainted, but in the meantime, the place is a mess.
Walt Guntharp


#10: Can't live with vent-free

I currently own a vent free fireplace in Orlando and am in negotiations with my home builder over it. We can't live in the house when it is on! He is offering to return some of the money paid for it and remove it and leave a useless space for the fireplace, or vent it. I think I want it vented, with glass on the front and proof that there are no leaks. He cites two studies done by the manufacturer that say the fireplace doesn't have harmful gases and was built to code. But there is a terrible odor that causes your eyes to burn, throat to itch, and eventually you get a headache.
John Edvardsen


#11: Headaches, dizziness, noxious odor

I read your Q&A about vent-free stoves. I have a [popular vent free model], and for 2 years I've been trying to make it so it doesn't smell and give me headaches and dizziness. I don't leave it on for more than half an hour because I can't stand it, so leaving it on too much is not the problem. It is in a large room with lots of windows and an open hallway; the noxious odor goes upstairs, so I know the problem isn't ventilation or the wrong size space.

I've done the burn-off routine, and the shop that sold it to me gave me replacement logs, but the problem persists. After reading your site, I know I'm not crazy. The dealer will not take it back, and I'm done trying to make it work. Can you give me any info to get into direct contact with [the manufacturer]? There is no email address at their website. You have my permission to forward this to [the manufacturer] or post it on your Q&A page.
Marbet Wolfson
Exeter, NH


#12: Wife has headaches

Hello - We recently purchased a vent free gas fireplace for our home. My wife started getting terrible headaches when it was on. We stopped using it and turned the gas off to it and her headaches went away. Is there any way to properly vent a ventless fireplace or do I need to purchase a new one?
Clyde Myers

Sweepy Hi Clyde,
Unless your vent-free was designed with the option of installing an exhaust vent (some are), there is nothing you can do with a vent-free except replace it with a vented model.


#13: Vent-free manufacturer gets 100 complaints per day

I'm so glad I came across your web site. I purchased a propane vent free gas log set during 2000. I have been unable to use it because of the smell. I've made various attempts to correct the problem: I let it burn off, I followed the manufactures recommendation and burned it on high for eight hours, I opened the windows, I've done everything to get rid of the exhaust / C0 smell. Nothing works. I've had the propane company check the recommended flow rate / pressure rate, in fact I had two companies do it. No one has offered to replace the log set, the seller told me to contact the manufacture, the manufacture hung up on me when they couldn't answer my questions. The vent free set burns our eyes, makes us dizzy and affects our throats and noses. No one will tell you this, everyone I talk to tells me my set is unusual, normally they can't smell a thing.

When I called the manufacturer, I heard another operator telling the caller he gets a hundred complaints a day. I couldn't tell what the complaint were, but I'll bet it's the smell. I was told by the manufacturer, get rid of the candles, don't buy new carpet, don't use spray cleaner, don't paint, on and on.......Believe me, I will not operate my vent free system. I will, when I can afford it, purchase a vented unit.....And I didn't tell you about the moisture, film on the windows and the complaints from visitors.

So I'm stuck with a lemon, but others beware, I have nothing to gain by telling you the truth about vent free gas logs. Be smart, you just can't breath the fumes.......Thanks for allowing me to address this issue. I wish I had found your site before my purchase. And to think I was going to invest in another vent free system thinking my first set was not operating properly.

Thank God for the internet and The Chimney Sweep.
Gary Gingrich


#14: Suffering from black lung

We too had soot damage in our home from vent free gas logs, to the tune of $41,000. In addition I started experiencing shortness of breath. After 3 months of tests I had a lung biopsy which showed that I have "black lung". Both lungs have soot inside and outside. This is something that will not go away. I'm going to the University of Michigan Medical Center today with the hope of finding out what will happen from this point on. I was told that my lungs are worse than those of a coal miner exposed to coal dust for over 20 years. In addition to the lung problems, I have a heart condition developing because of the lack of oxygen going to the heart. I have read many of your comments and encourage everyone to be checked. It's quite apparent that some of the manufacturers appear to hiding something. The logs we purchased have been discontinued and the manufacturer refuses to say why.

If anyone has similar conditions please contact me at [email protected].
Greg C. Filer


#15: "Shoe Polish" on walls

I found your site fascinating.. wish I had seen it before I purchased my gas logs... now... to my question.. my husband and I recently retired to the country. We purchased a lovely double wide home for this purpose. We had ventless gas logs installed into our fireplace and sat back waiting for cold winter days and nights. It has been two winters now and holy smokes I've noticed the walls of our new home are reddish brown and yellowed as if this home were 50 years old and neglected. The entire house will have to be repapered and painted as soon as the spring thaw occures. I cleaned a picture that hangs over the mantel and the rag was totally brown as if shoe polish had been wiped up with it. This must be very unhealthy to our breathing equipment. Now, is there any way I can hold the manufacturer responsible for the damage to my home?
Thank you.

Sweepy Hi Pat,
We're not lawyers, but it might be worth consulting yours.


#16: Sick of soot, smell

We have been experiencing soot problems on our ceilings in a huge family room that has a ventfree gas log set up. It is propane based and I am considering replacing it. What do I have to do to replace it? The company that installed the gas lines and tank stated I just needed a hood to push the heat into the room more. I got the hood and it has not helped. Also, my husband hates the smell which goes upstairs even when the unit is on low. Needless to say, we rarely use it and it cost a lot of money to install. By the way, it is in a regular masonry fireplace that has glass doors and a screen. Can you please advise me?
Mary Jacobs
[email protected]

Sweepy Hi Mary,
If you're mostly looking for the aesthetics of the fire, you can replace your vent-free gas logs with a vented set: you'll find the flames are MUCH more realistic in vented log sets. If you'd like to be able to turn off your furnace while you enjoy your fire, consider a direct vent gas insert. In the sealed environment of an insert, the flame display is positively astounding.


#17: Mom belatedly diagnosed with CO poisoning

I was so relieved to find your site so I could send my mother letters that would validate her as to her health problems of the last two years. She has a ventless system in her new home and her health problems began the first winter of use - it was run 6-8 hours a day. She had sinus problems, headaches, lethargy, dizziness, disorientation, hallucinations and eventually breathing problems. In eight months of use she went from 140 pounds to 99 pounds and when tested at 99 pounds she had a lung breathing capacity of 21%. She was sleeping on the couch most of the day. My sister and I felt like she was dying before our eyes. The doctors were stumped and ran test after test including 2 aids tests and a lung cancer screen.

After the fireplace was turned off for the spring/summer season of 2001 she began to feel much better. She still has residual symptoms - shaking, dizziness, breathing problems and confusion. Her lungs have been permanently damaged and her lifespan has been shortened by several years.

The fireplace manufacturer denies responsibility but is going to run the fireplace and do a CO test. It is very hard to prove that the fireplace is responsible for her condition. We are searching specifically for evidence that these systems could have been the cause of her problems. If anyone has any information about ventless symptoms that could help us PLEASE email me at [email protected].
Stephanie Mosely


#18: Appreciates the info2

I applaud your site and information about vent free appliances.
Keep up the good work.
Chad Clack


#19: Thanks for the website

I too purchased one of those vent-free gas fireplaces, and experienced the headaches, plants dying, and moisture problems. I also found the house had a mold problem. Your information about the CO issues explain a lot.
Thanks again for the VERY informative website.
Chris Hammerbeck


#20: Gas Company warns against buying vent free

I was very close to buying a vent free fireplace for my home. I just happened to call my gas company to see what the cost would be to install gas lines for this. The man I spoke to mentioned that I may want to think twice about getting a vent free model due to the odor. He said he had a customer who had one installed before talking to him and they are extremely upset about the odor. He told me he just wanted me to be aware of this before spending a lot of money on one. Well, I am thanking him a thousand times over. After he told me this, I decided to do a search on the Internet about odors emitted from vent free fireplaces, which is how I found this web site. After reading these letters, I am so glad that I didn't waste my money! Thank you so much for this information. If I ever buy a gas fireplace, it will be a vented unit only.
Dianne in Ohio


#21: Getting rid of vent free logs

We are replacing a [vent free] log set. Thought I was alone in my complaints until I read your site. Both the manufacturer and my installer acted like I was the only one who had these odor and health complaints. Even with a CO2 meter which read 0, we still felt sick. On top of that, we had mechanical problems, and even though the working parts of the unit were replaced, still had the same problems.
Thank you for refusing to sell vent free products.
Karen Rossi


#22: Will conversion from LP to natural gas stop "room poisoning"?

We have a ventless propane fireplace. We've learned it's poisoning the room with black smoke and causing all sorts of problems. Can we convert this ventless to burn natural gas? What are the health problems associated with natural gas, and the difficulty converting propane to natural gas? We might also want to use the same system upstairs if possible.
Please advise.
Thanks, Kevin

Sweepy Hi Kevin,
Converting your vent free fireplace from propane to natural gas won't affect the combustion emissions that are poisoning your room; the emissions from both fuels contain the same poisons. If you want to eliminate the room poisoning, your only option is to replace your vent-free with a vented model.


#23: Second try for vent free, having same problems, looking for support group

We bought our first [vent free] in 2001, and it sooted up our house. The serviceman the dealer sent out to inspect it said the [vent free] was faulty. We believed the dealer when he said no safety problems had been reported, and that this was just an isolated incident, so we purchased a replacement. The second [vent free] has a redesigned burner (the company is saying this was done for cosmetic reasons only), and although it is not emitting soot that we can readily see, our home still has damage from soot. After we paid for painting & cleaning at the end of the first season and had the heater cleaned it emitted soot again the following season. My daughter has recently seen her doctor because of severe headaches. We had no idea that the [vent free] could be causing this. I am terrified now.

I have questioned the manufacturer repeatedly about safety, and about the fact that we're living with the soot. The manufacturer and their lawyers are denying that the [vent free] is malfunctioning. Instead, they have said that it wasn't properly installed and that maintenance wasn't done, that the report the dealer sent in said that the [vent free] was clogged with dust and debris.

Is it possible to let the persons who have contacted your web page know that they should contact the U.S. Consumer Product Safety Commission in their area regarding problems they have with their vent free heaters? I have also contacted the Attorney General's Office and will not stop until something is done to stop the danger sold to us. If there is an organized support group please E-mail me at [email protected]


#24: Removing vent free fireplace because of toxic by-products

I recently finished my basement and decided to install a ventless fireplace to help heat the basement during the winter months. I was assured from several different store owners that vent free is completely safe, and that they burn so efficient (99.9%) that there is no concern over carbon monoxide (CO) levels, smell, or O2 depletion. My basement is 1200 sq. ft. and open. The fireplace was installed by a licensed workman. Despite turning the gas log set on low and allowing for adequate ventilation, the unit still produced a lot of odor and high levels of CO (over 20 PPM within 1 hour). I called the store where I bought the unit and they said that I should try "curing the logs" by burning it on high for about 6 hours. I explained that this does not account for the high level of CO. He said that up to 30 PPM is considered safe. I did a little research, and it turns out that IAQ guidelines allow a MAXIMUM CO level of 25 PPM/1 hour. In addition, I removed the logs and the burner unit still produced high levels of CO and odor. For the safety of my family and those who may purchase our house in the future, I am removing this fireplace. I believe that anyone considering buying a vent free should use common sense in this decision. Natural or LP Gas fuels produce toxic by-products. Period. The "studies" referenced by many sellers of vent free fireplaces are sponsored by the vent free gas log industry, and the results are inherently biased.
Mark Caswell
Saline, MI
[email protected]


#25: "Horror Stories" help make decision for vented fireplace

I went to three fireplace stores today and each salesperson told me that the vent free models were hands down a better choice. I just came across your site as I was looking for vent free fireplaces online. After reading the countless emails of horror stories regarding vent free fireplaces, I have decided to purchase a vented model instead. I am shocked that these vent free models can still be sold with all the health related illnesses they can cause. I'll make sure to sway people away from vent free fireplace models in the future.
My family and I thank you.
Chris and Erin Minchk
[email protected]


Page 1 (Letters 1-25)     Page 2 (Letters 26 - 50)    Page 3 (Letters 51 - 75)    Page 4 (Letters 76 - 100)    Page 5 (Letters 101+)


Read about how much CO2 a vent-free fireplace exhausts into the breathing space

Read about a recent study of the effects of long-term exposure to CO gases

Read about respiratory irritation from vent-free exhaust in the breathing space

Read a posting about vent-free gas appliances from an indoor air quality scientist

Read what Consumer Reports Magazine has to say about vent-free products

Read letters in defense of vent-free products

Read our opinion about vent-free gas appliances

Read about a 2016 ASHRAE standard that could eliminate the entire vent-free product category in the US

Have a vent-free experience you'd like to report?  Here's a link to the Consumer Product Safety Commission website.


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