On line you can check out the cost of various fuels per million btu. Cut wood is one of the least expensive ways to heat a home. Growing up we never paid for wood, always sought out free junk wood and I just cleaned the chimney a few times a season. Now that I have a child with asthma and a home that is only served by electricity I have had to rely on heat pumps and a pellet stove. (Puffs of smoke from wood stove when opening the door to feed wood are a problem for asthma.) Cold days when the heat pumps start cutting in electric resistance heat we run the pellet stove. It was the largest I could find (E----o Maxx) and holds three bags of pellets. The fan is LOUD - similar to a window AC unit on high (moved the TV to another room). Having used a wood stove for many year (before child) I can give first hand benefits of a large pellet stove. 1. No smoke or dust in the house. 2. We leave it unattended all of the time, it can even be wired to a thermostat. 3. Simple operation - don't have to adjust or babysit the fire. 4. This year I bought 2 tons of pellets for about $360 stored in the garage. I am fine with spending the money for the convenience.

I looked around at the different types of fireplaces and the choices are overwhelming. I don't know which one is appropriate for my application. Here's my situation: There's a chimney with a hole in it, which I believe was used for a wood stove or pellet stove vent. I want to convert that to a fireplace, preferably propane. Is there something that will just hang on the wall with a vent to the hole in the chimney?

No, it's not. Gasd and pellet stoves concentrate heat in limited areas and the heat is much less intense that with wood as a fuel. And a wood stove requires quite different venting ans air supplies. So don't even try. It would probably void your fire insurance if a fire happened.

I have not needed to change to propane with an old classic range, only the new style. However, it seems clear to me that you would only need to adjust each burner to your own desire. The nice feature about open burners is that you can control gas volume with an adjustable nut and you adjust air volume with a slide shutter that you just push more open or closed by hand and a screw driver. More gas, more air; less gas, less air; just barely no yellow flames; no problem.