has anybody ever heard of such an animal ? I have not, and it seems like an obvious idea, so I figure there must be a problem – maybe air supply…
I was thinking of making one out of an old wood stove, just putting in a gas bar like in the back of some fireplaces – so somebody tell me why I can’t before I blow myself up….
Replies
The mixing of fuel types as a heating unit or flue space is not code permitted.
Gas requires a constant regulated amount of air to allow a complete burn. Gas burning creates a flue exhaust tnat has water vapor, co2 and co. The damper setting would have to remain at an optimum setting,
Wood burn rate is regulated by variable damper and when the damper is closed down the unburned wood becomes charcoal or snuffs out. Wood gases and creoste are by products of wood burn and will coat the lining of a chimney.
If you add the gas's water vapor to the creasote lined chimney you will have large reosote crystals forming, which when you burn the next load of wood may generate a flue fire. You don't want to experience a flue fire!
How can you keep the wood ash from contaminating the burner orfices and venturie tubes. The wood fire will corrode the gas burner components. The gas valves and pilot light assemblies will not tolerate the a hot bed of burning coals.
To best of my knowledge............Not a safe do-able concept!
.............Iron Helix
ok - so, what I'm hearing is, you're jealous of my genius and want to steal my idea...
but seriously, thanks for disabusing me of a crazy notion - I knew there was an obvious problem...
does this mean those old fireplaces with the gas bar in back are at least noncompliant and possibly dangerous?
The "gas bar in the back of a wood burning fireplace" was installed to assist the inept with the lighting of the logs in a wood burning fireplace. After the logs were started then it is supposedly manually turned off.
Many of them were manufactured out of a simple piece of pipe, with a manual valve in the masonry outside of the firebox. The use of safety valves and pilot lites was omitted. Considered okay in those days but not so now.
Yes I would consider them as noncompliant and dangerous.
Newer devices may have the safety stuff, but I've not seen one installed. Maybe someone else has had other experiences. Or a fireplace shop could fill in the blanks on availability.
Everyone today is into the "ventless fireplaces"....which is another safety problem in itself.
Secondly the wood burning fireplace is a full draft chimney which allows a draft that would handle the gas "log lighter" and the wood fire. Fireplace flues require cleaning to remove creosote build-up. F/Ps do not accumulate creosote as quickly and in the quantities a closed chamber wood fired heater does due to the limiting damper.
...............Iron Helix
Are you talking about wood-burning supplemental heaters for forced air systems. We have one in our house made by Johnson Energy Controls, but have never used it because our flue tiles are broken. It has blowers that send hot air into the furnace return and a flue to the chimney.
Aaron
no, but that's an interesting idea - I assume the flue gasses are isolated to avoid the problems pointed out by Iron Helix...?