gas fireplaces vented or ventless?
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I’m remodeling the living room in the house i just bought and the wife wants to add a fireplace. All the fireplaces at Lowes or home depot are ventless. I can see how these would be easier to install, not having to cut a hole thru the wall to vent. I am going to put it on an outside wall regardless,the directvent fireplaces i have researched are more expensive and you have to buy the double wall pipe ,which is also expensive. What are the pros or cons to either system?
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If you like the idea of loading your house with water vapor and other combustion byproducts, possibly including carbon monoxide, you should definitely go ventless. Otherwise, I'd suggest venting.
Andy Engel
Senior editor, Fine Woodworking magazine
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This post, and your answer, could not be more timely. My DW and I just moved into a new home that is equipped with a vent-free LP gas fireplace. I spent several hours today reviewing the FHB archives and came to the same conclusion. Thanks for the confirmation.
They are designed and tested to be safe for supplemental heat. Some states prohibit ventless appliances for primary heat.
Despite their testing and certification I am skeptical that it is impossible to develop problems many years down the road, so I would be leery of installing a ventless gas appliance.
>>They are designed and tested to be safe for supplemental heat. Some states prohibit ventless appliances for primary heat.Every building code I know of says you have to use in accordance with the manufacturer's specs.The manufacturers say they are only for supplemental heat.Thus, every state forbids them as a primary heat source.And you can't use them in bedrooms or baths, and you have to open a window or door.If you use them right, they're pretty stupid.If you use them wrong, they can be deadly.
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Sojourners: Christians for Justice and Peace
If you use them right, they're pretty stupid.
If you use them wrong, they can be deadly.
I like that. Hope you don't mind if I use it.
I have a ventless fireplace for ten years and it is very efficient it does add some water content but not as bad as the naysayers say. Mine is set up in my greatroom/kitchen/dining area which is 44'x 24' in 10' ceiling I don't open any windows and it does fine. I do recommend a carbon dioxide detector as co2 is a silent killer but with precautions I feel it is a viable source for heat.
ANDYSZ2I MAY DISAGREE WITH WHAT YOUR SAYING BUT I WILL DEFEND TO THE DEATH YOUR RIGHT TO SAY IT.
Remodeler/Punchout
>>I don't open any windows and it does fine. I do recommend a carbon dioxide detector as co2 is a silent killer but with precautions I feel it is a viable source for heat.A CO2 detector won't do squat for carbon monoxide <G>And there are varying sensitivities for CO detectors. And some folks are more vulnerable than others. The $20 aren't worth the money in my opinion. The $40-50 ones are kind of ok for healthy adults who keep their combustion appliances well tuned. For anyone else, a low level monitor is only $125 or so. What's your life, or your health worthSure, there are millions of "ventless heaters" out there that don't cause problems. (They do vent - inside: using one is like choosing to live in a chimney.)And there are some ventless heaters out there that kill people.And probably more out there that cause significant health problems without people knowing it.Each person has his or her own way of evaluating risk.The way I look at it, why take such a high risk for such a small monetary reason?Your mileage may vary.
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Sojourners: Christians for Justice and Peace
I'm a bit curious about this. If one lived in a fairly old "loose" house, at 99% efficiency, you're getting, what, 1% "bad" gases?I wonder how much "bad" gas a regular HW water or non-energy efficient furnace gives off in comparison?Figure, a decent-sized area, as supplemental heating (meaning you don't run the ventless fireplace more than what, 3-4 hours/night or something during the week)?Now, if one lived in a 'tight' house, probably not a good idea (but then you'd probably not need supplemental heat).In my house, it would probably work fine (it's an old house, fairly loose, and dry as hell in the winter so I have to run a supplmental humidifier for the central air).BUT, it's nigh to impossible to find a ventless one around here, so I ended up with a direct-vent unit (only 77% efficient).Is there a big cost factor between the two? I honestly don't know (since I couldn't find one)--even though they are allowed in my municipality.I'd think the efficiency of the unit would affect heating costs somewhat, but then again, I wanted it mainly for aesthetics (as opposed to a regular fireplace where all the air goes up the chimney)--NG insert, BTW.Just some random thoughts.
99% = 1% bad gass is bad logic.
100% efficiency means all of the heat produced stays in the house. You could still be producing lethal amounts of CO.
Thanks, I did not realize that. The literature from a ventless unit makes it seem like it's "so efficient" that all but 1% of the bad stuff is consumed/burned, etc.Having never priced one, I don't know what the cost difference of the unit itself is, although I'd hazard that installation is a big chunk of the difference.
Vent free fireplaces reley on an "oxygen depletion sensor" that will shut off the pilot when the o2 reaches 18.5%. o2 is normally 20.9%. when it is reduced to 19.5% that means something else is there and that % translates to 75,000 ppm. And the fireplace can still burn. Not a pleasant thought.
here is an interesting link.http://www.occupationalhazards.com/safety_zones/31/article.php?id=1502
>>I'm a bit curious about this. If one lived in a fairly old "loose" house, at 99% efficiency, you're getting, what, 1% "bad" gases?As Rich noted, efficiency relates to conversion of potential heat into actual heat.So long as a combustion appliance is operating properly, the CO produced is minimal.But if it isn't (and, in the case of gas log sets, that can include if the logs aren't installed and kept in The manufacturer's required positions -and they are rarely installed properly, in my experience) they can produce large amounts of carbon monoxide.Because the CO is in hot gases, it rises.The "safety" mechanism on ventless heaters is the "oxygen depletion sensor" aka the pilot light, which shrinks if oxygen levels drop too far and shuts off the gas flow.But the pilot light is at the bottom; and the CO moves up.If a door is open from the room the heater is in, the CO will spread out and up, leaving the heater merrily burning and spreading its deadly charms.
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Sojourners: Christians for Justice and Peace
This should be a "no brainer" but it's "all about the money". That's why the manufacturer's of the ventless make them, they can beat the competitors' prices easily and with a simple defence....."they're legal" and they are 100% efficient. The vented manufacturer's dealers have to justify the extra cost and that some heat is lost to the outdoors in the name of safety.
In Canada, residential ventless gas heaters are not allowed; we do have portable kerosene heaters though. It is recommended that windows be open while they are used......that increases heat loss!!!!