Replies

1. 
   jameshowison | Sep 29, 2021 02:21pm | #1

   A room outside the main envelope? Visible from the kitchen/great room through all glass doors, think a snug/reading/TV space. Could also be with operable large windows so that it's basically a screened patio for other seasons?

   Maybe a makeup air supply from outside that supplies cold air at the front of the fireplace, very much like a kitchen cooktop hood with makeup air. What I'm saying is basically put an open fire in a fume-hood :)

   Or a minisplit 1-1 running on cooling mode devoted to extracting the excess heat :)

2. 
   user-5946022 | Sep 29, 2021 03:01pm | #2

   I agree with you - direct vent so you do not need any makeup air. Most of the direct vent gas fireplaces have a kit you can buy to convert from natural gas to propane gas.

   The available direct vent options are very limited, and very leaky. The HeatNGlow Slimline Fusion or SL3x in 32" put out 11.5k btu an hour. Someone makes one that puts out only 8k btu an hour, which is about the smallest I ever found, but I don't remember which company - google around and you can find it.

   There is definitely a business opportunity to make a very tight direct vent gas fireplace that can be easily converted between natural and propane gas. This is a much more cost effective and quieter solution to backup heat in a power outage than a generator, and add ambiance in between.

1. Expert Member
   BILL WICHERS | Sep 29, 2021 03:49pm | #3

   >"can be easily converted between natural and propane gas. "

   Usually the change is simple, often little more than swapping out an oriface in the gas valve assembly if even that. As far as I know, pretty much every gas burning device can be easily converted between natural gas (methane) and propane. That goes for cooktops, furnaces, generators, water heaters, and even fireplaces.

   I agree to only consider direct vent fireplaces here. Direct vent fireplaces are equivalent to "sealed combustion" water heaters and furnaces in that they have a seperate air path for combustion air. This means no worries about makeup air being pulled from inside the home, and no worries about combustion byproducts getting into the home, either.

   Bill

3. 
   CheeseCurd | Sep 29, 2021 04:42pm | #4

   Some of the higher end gas fireplaces (Napoleon, Mendota, etc.) have vent kits that allow you to vent the heat to the outside. These are marketed for allowing the fireplaces to be used in warm weather. Perhaps this is an option. The typical fireplaces from those manufacturers put out 30,000+ BTUs, so I assume that would quickly over-warm the house.

4. 
   walta100 | Sep 29, 2021 08:09pm | #5

   I have a Heat & glow cosmo42 gas fireplace. It seems to be very tight. As a heating appliance it is NOT very effective, as a decorative item to set a mood it is great. I understand conventional style units do put out a lot of heat.

   I did take the time fire calk around the flue pipe and make sure the fireplace is fully inside my conditioned space and not on an exterior wall.

   http://www.heatnglo.com/Products/Cosmo-SLR-Gas-Fireplace.aspx

   Walta

   A similar thread

   https://www.greenbuildingadvisor.com/question/suggestions-for-natural-gas-direct-vent-fireplace-that-is-super-air-tight