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Rasmussen Alterna ventless burner kit with gray fireballs and media color samples
  • Rasmussen Alterna ventless burner kit with gray fireballs and media color samples
  • Rasmussen Alterna fireballs shown close up with seven available color options
  • Rasmussen Alterna burner kit safety pilot options, including manual and remote controls
  • Rasmussen Alterna burner gas connection diagram with supply line and flex connector
  • Rasmussen Alterna burner kit chart listing fireplace size requirements and dimensions
  • 20-inch see-through fireball burner kit with brown media and a metal safety pilot valve
  • 20-inch see-through fireball burner kit with light gray media and wired safety pilot valve
  • Rasmussen 20-inch ventless burner kit with beige fireballs and electronic ignition components
  • Rasmussen 20-inch ventless burner kit with brown fireballs and remote control components
  • Rasmussen 20-inch ventless burner kit with natural fireballs and electronic ignition components
  • Rasmussen 20-inch ventless burner kit with beige fireballs and a manual safety pilot
  • Rasmussen 20-inch ventless burner kit with brown fireballs and safety pilot controls
  • Rasmussen 20-inch ventless burner kit with natural fireballs and a manual safety pilot
  • Rasmussen 20-inch ventless burner kit with dark gray fireballs and electronic ignition components
  • Rasmussen 20-inch ventless burner kit with beige fireballs and remote control components
  • Rasmussen 20-inch ventless burner kit with natural fireballs and remote control components
  • Rasmussen 20-inch ventless burner kit with dark gray fireballs and a manual safety pilot
  • 20-inch see-through fireball burner kit with beige fireballs and safety pilot controls
  • 20-inch see-through fireball burner kit with natural-tone fireballs and safety pilot controls
  • 20-inch see-through fireball burner kit with dark gray fireballs and remote control components
  • 20-inch see-through fireball burner kit with black fireballs and electronic pilot components
  • 20-inch see-through fireball burner kit with adobe red fireballs and electronic pilot components
  • 20-inch see-through fireball burner kit with dark gray fireballs and safety pilot controls
  • 20-inch see-through fireball burner kit with black fireballs and manual safety pilot
  • 20-inch see-through fireball burner kit with light gray fireballs and electronic pilot components
  • 20-inch see-through fireball burner kit with adobe red fireballs and manual safety pilot
  • 20-inch see-through fireball burner kit with black fireballs and remote control components
  • Rasmussen 20-inch ventless burner kit with light gray fireballs and gas valve
  • Rasmussen 20-inch ventless burner kit with adobe red fireballs and remote controls
  • Rasmussen 20-inch ventless burner kit with black fireballs and safety pilot assembly
  • Rasmussen 20-inch ventless burner kit with light gray fireballs and remote controls
  • Rasmussen 20-inch ventless burner kit with adobe red fireballs and safety pilot assembly
  • Rasmussen 20-inch ventless burner kit with brown fireballs and ignition components
Rasmussen Alterna Ventless FireBalls See-Thru 20-Inch Burner Kit

Rasmussen
Starting At $1,158.00

Rasmussen Alterna Ventless FireBalls See-Thru 20-Inch Burner Kit

SKU: DF-ANB20-B-Config
Fuel Type:Propane

Price:

Starting At $1,158.00
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Optional Accessories:
Description Specifications What to Consider Downloads
Product Features
  • See-Thru FireBall Design - Features fourteen smooth, full-round 4-inch FireBalls arranged in two tiers on each side for a contemporary flame display.
  • Dual-Sided Flame Display - Designed for see-through fireplaces, providing an attractive view of the flames and FireBalls from both sides.
  • Improved Flame Performance - Redesigned burner step and increased clearance help promote better flame movement and presentation.
  • Discreet Ball Supports - Individual supports securely position the FireBalls while minimizing visible hardware for a cleaner appearance.
  • Durable Steel Construction - Mild steel chassis with a high-temperature black powder-coated finish and a heat-resistant painted burner.
Product Description
The Rasmussen Alterna Ventless FireBalls See-Thru 20-Inch Burner Kit delivers a contemporary fireplace experience with a distinctive arrangement of smooth, full-round 4-inch FireBalls and lively gas flames visible from both sides. Designed for see-through fireplaces, this vent-free system features individual FireBall supports for a cleaner presentation, an improved burner step engineered to enhance flame performance, and increased clearance for better flame movement. Its durable mild steel chassis features a high-temperature black powder-coated finish, while the burner is protected with high-temperature paint. Designed for indoor installations, the kit includes fourteen smooth FireBalls arranged in two tiers on each side, creating a balanced flame display that can be enjoyed from adjoining living spaces. The double-face burner design provides a striking contemporary centerpiece while maintaining a streamlined appearance with minimal visible support hardware.
⚠️ WARNING: This product can expose you to chemicals including LEAD AND LEAD COMPOUNDS, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov/.
Choose Product Options To See Full Specifications

Vented vs. Vent-Free

Vent type refers to how the fuel emissions are managed, your selection should be based on they type of firebox in your home and ensuring it meets your local codes.

Vented
  • Most popular option for gas logs
  • Gas logs must be used in a firebox with a working chimney flue
  • Can be less efficient as a heat source because of the open chimney
Vent-Free
  • Can be used in any approved firebox - with or without a flue
  • Very efficient energy source as no heat is lost through the chimney
  • Requires an oxygen depletion sensor to safely monitor gas emissions
  • Some states do not allow vent-free units - check your local codes

Choosing Gas Log Size

Know your fireplace dimensions - Measure front width, back width, the depth and the height of your firebox.

Before You Begin:
  • Take clearances into account to avoid any overheating of combustibles
  • Be sure to leave room on the sides for a valve/remote system if using them
  • Gas log sets can range anywhere from 12 to 96 inches, but most common sizes range from 18 to 30 inches
Looking For a Custom Size?
  • Many brands offer the ability to create custom logs/burners to fit any firebox
  • Usually standard sized log sets will fit nearly any firebox but some fireboxes are unique

Outdoor vs. Indoor

Because of their ceramic construction, many log sets can be used indoors or outdoors - with the proper considerations.

Indoor Log Sets
  • Can use black steel or stainless steel burners with confidence
  • All safety pilot options are able to be used
Outdoor Log Sets
  • Be sure to use a stainless steel burner to withstand the elements
  • Safety pilot kits may not be an option if you can't protect them from weather
  • Match light is the most reliable option

Gas Supply

For gas log sets, burners will be supplied from the same gas that supplies the rest of your home.

Natural Gas
  • Most common gas type for gas logs
  • Almost all homes in urban/suburban developments will have access to natural gas
  • Natural gas does not sink, which helps avoid the build-up of gas on the fireplace floor
Propane
  • More common for rural homes
  • Often runs off of a large stand alone propane tank
  • Propane is heavier than air and will settle on the fireplace floor - a reason why most manufacturers require the use of a safety pilot kit to help burn excess gas before it settles

Ignition and Controls

Ignition/controls refer to how the gas log set is started.

Match Light
  • Most basic and inexpensive ignition method
  • Manually open your gas valve and light the burner with a lighter or match
  • Flame height can be easily adjusted
  • Very reliable - all mechanical parts (nothing should ever break)
Manual Safety Pilot
  • A pilot system allows convenient ignition by having an open flame source that ignites the main burner when the gas valve is opened
  • Features a standing pilot (the pilot light will stay lit at all times)
  • Often times can be paired with a remote, wall switch, or thermostat
Electronic Ignition
  • Similar to a manual safety pilot but allows the pilot to be lit automatically
  • The pilot can be standing or intermittent (shut-off between uses)
  • More energy efficient by shutting off the pilot in between uses
  • Can be paired with a remote control, wall switch, or thermostat

Log Set Profiles

There are two types of log styles - one-sided and two-sided

One Sided Gas Log Sets
  • For installation in a traditional fireplace with only one viewing angle
  • Most common log set option - the logs are designed with this profile in mind
Two-Sided Gas Log Sets
  • Also referred to as "see through", "dual face", or even "peninsula" style log sets
  • These logs are designed to have multiple viewing angles - either two sided or three sided in some cases
  • Very contemporary option to join two rooms together with one fire feature
Product Resources

Rasmussen

Rasmussen is a leading brand in the fireplace industry with over a century of experience. Their gas fireplace logs are crafted using a meticulous process, resulting in some of the most realistic logs available. Rasmussen offers a variety of gas log sets, fireplace remotes, components, service parts, and accessories to enhance any firebox. The company stands behind their products, offering a lifetime warranty on all log castings and a two-year warranty on burners and grates.

Shop All Rasmussen

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