RealFyre Sizing Guide
Sizing a gas log set is fairly straight forward and most fireplaces can be sized using general measurement guidelines. Certain fireplace shapes (for example, the steep taper and shallow depth of a Rumford Fireplace) may require additional consideration.
In general, for vented sets with a safety pilot control, you should select the next smallest size. For example, if the rear width is 24" and you wish to use a safety control, rather than a 24" set you should select a 20" or 21" set.
RealFyre Vented Gas Logs are for use in fireplaces in which it is safe to burn wood. The flue size (chimney opening) must be sufficient to exhaust all of the products of combustion (soot, carbon monoxide, carbon dioxide and water vapor are the primary products) up the chimney. If not, or if other conditions exist that prevent full venting, these combustion products will enter the room, which can be harmful to health and property. A vented gas log set is not a cure for a "smoking chimney".
RealFyre nominal log set sizes are based on the approximate length of the front log (or combined length of two-piece front logs) of the set. These measurements should be taken from the fireplace floor, inside the hearth or lip of the fireplace, and behind any wire screens or railing that may be permanently attached to the fireplace. In deeper fireplaces, front width measurements can be taken 6" to 8" from the front, allowing better centering below the flue of the fireplace.
All vented pan burners will produce soot, therefore a vented gas log set does not correct a "smoking fireplace" (one in which smoke and soot enter the living space). The most tell-tale sign of a smoking fireplace is a blackened fireplace face immediately above the fireplace opening.
There are only two places for the soot and other products of combustion to go: (1) up the chimney, or (2) into the room. The gas log set does not influence where it will go Potential reasons for soot going into the room include:
- Damper not open or not open far enough.
- Too small of a flue.
- Too large of a fireplace opening in comparison to the flue opening (1/10 rule. For masonry chimneys, most codes require that the area of the flue be no less than 1/10 of the area of the fireplace opening. Metal chimneys can exhaust well with smaller flue size.).
- Obstruction in the chimney. Bird nest, creosote build-up, etc.
- Negative room pressure created by kitchen exhaust fans, ceiling fans, etc.
- Log set installed too close to the opening. The combustion products are spilling out of the opening into the room.
- Air flows outside the house that do not promote proper draft. May require lengthening the chimney stack or the installation of a chimney cap.
- Chronic "smoking fireplace". Fireplace design related.
- Chimney "cold block" that inhibits air flow up the chimney.
Use of the gas log set (or wood burning, for that matter) should cease until the source is identified and corrected. Failure to do so may result in harm to life and property. If unable to correct the smoking condition, the only gas log set that can be safely used is a vent-free gas log set (such as the Rasmussen Chillbuster series), which are certified to ANSI Z21.11.2, the national unvented heater standard. This standard is the most restrictive of all gas appliance standards. This standard does not permit sooting and allows the lowest level of carbon monoxide of all gas appliances.