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My client would like to purchase a ventless heater to put in his blocked up fireplace

rockinroger | Posted in General Questions on

I understand they can run on natural gas, LP gas, or denatured ethanol.
Are these units putting out any substantial heat or are they more decorative?

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  1. n9T92uZrBV | | #1

    Ventless heaters are a bad idea. They are a step backwards from the invention of the chimney for keeping crud out of your breathing space.

  2. homedesign | | #2

    Agreed...BAD IDEA

    What would Bob Vila do?

  3. GBA Editor
    Martin Holladay | | #3

    Bad idea. Read Alex Wilson's blog: Avoid Unvented Gas Heaters.

  4. rockinroger | | #4

    Thanks for the replies.. I know nothing about them and it just might stay that way.

  5. mrbreadpuddin | | #5

    It might not be that hard to find someone to run a new liner up the old chkimney, that way you can instal any kind of heater you want to,

  6. rockinroger | | #6

    Mr. Goodwin,
    We've considered that option, but a lot of these old New Orleans, French Quarter double shotgun homes, circa 1865, have double sided fireplaces with a partition wall dividing the fireplace. A fireplace for each side with a common flue. To make things more interesting, right above the ceiling joists the chimney is offset about 20 degrees before returning to plumb and then going through the roof.
    We might just find him a good electric space heater, but with 12' ceilings that's not really too efficient.
    Wintering in Fla. might be cheaper! LOL.

  7. user-659915 | | #7

    Is the purpose of the exercise to find a good use for the old fireplace or is it to efficiently heat the home? If the latter, and if you can find a good location on an exterior wall, a room-sealed direct vent unit will be the no-fuss no-muss solution.

  8. 56i9GixV4K | | #8

    I don't know why a ventless heater was voted against so soon. They do put out heat. They don't make a mess and polute the air as Jeremy mentioned. A ventless fireplace would actually look great dressing up an old abandoned fireplace. I've got a great inventory, but send a message if you'd like to take a look. I'm not going to spam.

  9. kevin_in_denver | | #9

    You may think this answer is tongue in cheek, but I'm dead serious. Get a 43" plasma TV now on sale for under $400. The plasma screens put out more heat than any other style.

    In a family room, the TV and fireplace always compete for "center stage". When you put in a DVD of a fire, you have a very attractive "fire" that is putting out some heat, and zero carbon monoxide, and a "fireplace" that didn't force the TV into an awkward spot on the wall.

    A win-win.

  10. GBA Editor
    Martin Holladay | | #10

    Since unvented space heaters use your living room as a chimney, how can you possibly say that they "don't pollute the air"?

    Even if I were willing to ignore the other combustion by-products -- and I'm not -- they give off way too much water vapor.

  11. rockinroger | | #11

    Thank you one and all for your insights and thoughts. After considering them, we are going to see if we can get a flue liner down the chimney, and get a nice old -fashioned cast iron "cradle" with fake logs,and hook up some natural gas.
    It doesn't get that cold here in New Orleans, and this application is all about "atmosphere".
    Happy Holidays - Roger Steinbrink

  12. user-757117 | | #12

    I thought Kevin Dickson had a not-so-bad idea...
    I even found the article Martin wrote on the demise of the U.S. furnace industry.

    Well, good luck.

  13. GBA Editor
    Martin Holladay | | #13

    I assume you are referring to the April Fools' Day news report:
    Researchers Predict U.S. Furnace Industry Is Doomed

  14. user-757117 | | #14

    Martin, that's the one.
    April fools gag or not I think there's something to it.

  15. rockinroger | | #15

    As far as putting a flatscreen a fireplace, I took a nice old maple mantlepiece, turned it upside -down, built a base to raise it up, and added a few more sticks of moulding. I then used a nice old slab for the top & added some small crown moulding, a cove & it turned out awesome!

  16. smartadv | | #16

    This is an example of a lot of misleading and incorrect information being published on the internet.
    Vent free or ventless fireplaces have been in use for over 20 years. There are NO hard facts to back up these claims. Ventless fireplaces are 99% efficient safe and UL tested.
    Be careful of “self-proclaimed” experts who really don’t know what they are talking about.

  17. Expert Member
    Dana Dorsett | | #17

    Alan: Ventless fireplaces require sufficient ventilation to purge the moisture and other combustion products. They may be "safe" in leaky &/or over-ventilated homes, but there's no question but that they are a source of indoor air pollution.

    In green building air sealing the building envelope to minimize heating cooling loads due to infiltration is on the short-list, making this sort of appliance a "solution-problem", covering some of the space heating load, but creating a greater need for ventilation management with a higher ventilation rate than would otherwise be required. This is not a trivial problem to solve, and thus not a great way to heat a space.

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