Here is another previous post on the subject: posted by: renron on 12.19.2006 at 07:28 pm in Fireplaces Forum First, DON'T install a ventless fireplace!!! Even though the MFG.s will tell you the exhaust fumes are OK, do you really want to breathe them? Many people end up with Major Headaches and chronic breathing issues. Does it sound like a good idea to breathe burnt exhaust gasses? B type flue(vent) pipes are dual thickness pipes. A pipe inside another pipe, suitable for use at 1" or more to flammable materials. Outer casing pipe is sealed and will not conduct air. D (Direct Vent) type flue(vent) pipes are also dual layers but they are capable of exhausting burnt gas through the inner pipe and importing exterior(outside) combustion air for burning. Think of a straw inside a larger straw. Inside straw blowing, outside straw sucking outside air for combustion. A fan is usually used to help exhaust the burnt gasses. Details below: B-Vent (Natural Vent) gas fireplaces are designed primarily for decorative use. Generally they produce a larger and more realistic yellow flame. B-vent fireplaces are sometimes available without a glass window, so many homeowners are attracted to this design because of the open, realistic flame effect; some models do have a glass window so the existence of a window on a fireplace does not define its product classification. Natural vent gas fireplaces use room air for combustion and vent fumes through a vent or chimney that must terminate vertically above the roof line. The key to determining whether a B-vent fireplace will meet your heating needs is to check the manufacturer's listed efficiency rating (gas consumed x efficiency = heat output). While efficient, heater-rated B-vent fireplaces do exist, many lower quality "builder grade" fireplaces have no efficiency rating and, therefore, will not supply substantial heat. In fact, this category of fireplace will often use the greatest amount of gas at the lowest range of efficiencies. If you live in a warmer climate where you want the aesthetics of a fire without much heat, this may be the appliance for you. Likewise, bedrooms and smaller rooms may be a good candidate for a b-vent fireplace, but please check building codes to see if this class of fireplace is approved in your locality or for installation in the room where you'd like to use it. Local/national codes in some areas prohibit the use of b-vent rated appliances, especially in colder climates. Be aware that very "air tight" houses can cause performance problems with b-vent rated appliances, so please consult an experienced fireplace installer who can advise you on the proper installation and use you are considering. Direct Vent Fireplaces offer the most features with respect to gas consumption, efficiency ratings and venting options. A direct vent fireplace will always have a glass window because these fireplaces are sealed systems using a double walled venting system. Combustion air enters the appliance via one section of pipe while fumes and moisture are vented through the other pipe. Most often, a double wall "pipe within a pipe" system is used. Subject to each model's requirements for distance and offsets, direct vent fireplace venting may be terminated either horizontally or vertically. Efficiency rating will average 65% to 84%, similar to ratings on gas furnaces. Keep in mind that these appliances must "waste" some of the heat produced to create a draft of rising warm air to evacuate the fumes produced without aid of a forced air exhaust system. Think of direct vent fireplaces as a decorative furnace: the beauty of a realistic flame with high efficiency. This appliance is great for primary or supplental heating and for emergency backup heating as most work without aid of electricity. Because this is a sealed system that uses outside air for combustion, direct vent fireplaces are usually the favored choice among those in the fireplace industry because of their greater efficiency and exceptionally reliable performance. Hope this info helps, I am a General Contractor. Renron

Thanks for the info. I liked the look of the black enamel as it seemed more contemporary (but not too odd) but I noticed a whitish area on the enamel liner near where the flame had been once the fire was off. It was faint but I could see it from across the room since it was white on black and was concerned about how bad that would become over time or whether there was any way to get rid of it (cleaner, new paint, etc.). Has anyone had a black enamel liner for a few years to see how it holds up?

I've got to say that I hate our gas fireplace and would trade it for yours any day. Ours is just flicker of a yellow/blue series of flames that don't crackle or pop. I guess to each his or her own. That aside, if I was doing it again and wanted the heat advantage only, then I'd make sure to get one of the gas fired ones that have the blower and is somewhat sealed behind the glass. Otherwise, you still have the sucking of the cold air, but with none of the advantages of a real wood fireplace. I don't know the technicalities, but I'd shop around for several installers and see if you (they) can change the orientation and get at least 3 bids. Personally (although I'm not an expert) I don't see why you can't alter the flue/vent, but the cost would be more for sure. It's probably just up to the cost of redoing things and how much you are willing to pay. The stone veneer is a great idea and easy to do yourself. Also, consider stone tile. This post was edited by audiomixer on Thu, Feb 7, 13 at 23:20

Yup, if it was wood burning it's not a big deal to convert it back to wood. However if it was built with a flue for gas only that is where the problem lies. We opted not to buy the property in question but many we have looked at have gas. I'm trying to convince myself I'd be satisfied with gas. It is easy if you want to quickly warm up the area and see some "fake" flames. I just saw a new gas insert some friends put in their wood burning fireplace and it's the best one I've seen. Still nothing like the blazing wood fire we had this weekend in our Cozy Heat.