Gas Fireplace Inserts are used to convert an existing wood burning fireplaces, both pre-fab (zero-clearance) and masonry, to a more efficient gas appliance. They consist of a Gas Log set installed into a Steel or Cast-Iron Heat Exchanger and are usually sealed on the front with glass - the exception being Vent-Free gas inserts which are usually open. Many of these units have fans to move the heat, and are also available with remote controls, wall switches or wall-mounted thermostats.
These Gas Inserts are much more efficient than the Vented Gas Logs, and the sealed fronts (glass) provide an extra safety factor. Quality Gas Inserts can provide BTU outputs ranging from 10,000 to 40,000 BTU and can burn as high as 80% (+-) efficiency.
Most modern Gas Inserts are direct vent, which means they use a two-pipe system, one which brings combustion air into the insert and the other which vents the exhaust. With a direct vent, it is usually mandatory to completely line the chimney to the top with two Flexible aluminum or Stainless steel pipes. This assures proper balance of the intake and exhaust and assures safe operation.
Some Gas Fireplace Inserts are B-Vent, which means they use a single pipe system. These units are often less efficient than direct vent because they use interior house air for combustion. B vented units must also be lined to the chimney top, although with only a single pipe in this case.
Vent Free Inserts use no chimney at all, and so consist of only a metal box with a vent-free log set inside. The existing chimney is not used in this case. It may be that a vent-free insert offers no advantage over a Vent-Free log set, so prospective Vent-Free buyers should study the options carefully and consult with their contractor or fireplace pro.
Gas Inserts sell for $1400. to $3500+ with professional installation adding another $800 to $1500 (approx) to the price. This is typical a job for a pro - meaning an HVAC contractor, plumber or fireplace pro.
Make certain that your existing wood burning fireplace is cleaned well before installing your new gas fireplace insert!
If you like the idea of a Gas Fireplace conversion, and are looking for a unit to provide supplemental heating as well as the beauty of a flickering fire, check out the Gas Inserts at your local retailer or preferred internet merchant!