If you have ever experienced it, you know that sooting from a fireplace can cause unsightly damage throughout a home. In some cases, sooting from gas firelogs is caused by improper placement of the logs, such that flame impinges on the artificial log. When heated, the “log” will give off soot, so placement of the logs is important. Some manufacturers provide locating pins for the logs to rest on, so that proper placement is easier to achieve.
Propane or natural gas-fired gas logs are mostly decorative, but to provide some measure of functionality by recovering some of the heat output, some firelogs are non-vented. For such non-vented firelogs, the homeowner is not relying on a chimney with good “drawing” characteristics to prevent soot deposition in his home, but rather on efficient combustion.
Often, sooting problems with non-vented firelogs occurs when the primary air inlet openings become partially blocked with lint, dust, spider webs, animal dander, and the like. If air cannot flow freely through the openings, the mixture of gas and air becomes “rich”, resulting in inefficient combustion and sooting. Manufacturers of firelogs generally recommend inspection before each use and frequent cleaning of these openings, for example every three months.
The problem is that it is difficult to see the openings without use of a small mirror, short of removing the firelogs from the fireplace. The openings may be a series of small holes or slots; these openings are located where the smaller diameter gas tube from the gas control valve enters the larger diameter burner tube. Unfortunately, these openings almost always are best viewed from the rear, which requires a mirror. Once you have located the openings, you can blow air through them to dislodge the debris; a can of compressed air from a computer or electronic equipment supplier works well, particularly with the small “straw” that allows the airstream to be concentrated and directed.
Don’t forget while cleaning these primary inlets to also blow out the pilot inlet air hole, located in the tube a couple of inches upstream from where the pilot flame comes out when lit. Of course, the unit and pilot must be off during cleaning. It may be necessary to insert the “straw” from the compressed air can into a flexible drinking straw to make the 180 degree turn to blow through the air inlet holes from the front side of the firelogs.
With routine care and maintenance, you will continue to enjoy the warmth of the firelogs without the worry of a messy clean up.
Roger Davis, a senior consulting engineer at The Warren Group, is a licensed professional engineer in South Carolina, North Carolina, Alabama, Georgia and Mississippi. He holds a Bachelor of Science in Mechanical Engineering and a Master of Business Administration from the University of South Carolina. He’s also achieved a Certificate in Crane Safety from the Georgia Institute of Technology, Distance Learning and Professional Education Center, Atlanta, Georgia. Roger is a certified fire and explosion investigator and certified vehicle fire investigator. He is experienced with municipal water, sanitary sewer, and storm water system design, construction, and operations. His expertise also includes property damage and personal injury investigations involving municipal utilities. He is an accomplished gas and diesel engine mechanic and has more than 30 years of experience with hydraulic plumbing and piping issues. Roger has investigated claims and injuries ranging from pressure piping system failures and material and personnel handling equipment to large engine failures and fires involving machinery, generators and vehicles.