• What is the difference between a Direct Vent and Vent-Free unit?

    Vent-Free units do not require a flue while direct vents have a flue that must be vented outside through a wall or the roof. Direct Vent units have a fixed glass panel, while on Vent-Free models, glass fronts are prohibited.

  • How safe is a Vent-Free fireplace?

    Extremely safe. Vent-Free appliances have been sold in the USA since the 1960s and have an exceptional safety record. In fact, Vent-Free fireplaces represent the fastest-growing segment of the fireplace industry due to flexibility in installation. Each product must comply with stringent National Safety Standard called ANSI Z21.11.2b. Please visit for more information

  • What is the recommended room size for your fireplaces?

    Suggested 400 square feet space for our 3′ units, 500 square foot minimum for our 4′ units, either Vent Free or Direct Vent A minimum of 1,000 square feet for the 6′ Direct Vent.

  • How do I place electronics and artwork above a Spark?

    Please realize heat is a natural bi-product of our fireplaces. We know that heat rises, however, the direction in which air flows is completely unpredictable in any given room. Each installation is unique. Placing electronics and artwork above our fireplaces will have to be at the owner’s discretion and we therefore cannot offer any advice or recommendations, as there are just too many variables.

    Before installing a flat-screen TV, check with the manufacturer and/or store you where you purchased it. We recommend you place the TV at least 18″ above the top of the opening of the fireplace and more importantly, recess the front of the wall above the fireplace at least 4″ so the TV is recessed into the wall and out of the heat path.

  • Is electricity required for the electronic ignition?

    Yes, there is a 7v transformer that should be plugged into an 110v outlet.

  • Why do some pictures show an air grille on the Vent-Free unit?

    An air vent is required for all vent-free fireplaces. There are different techniques to conceal an air path underneath the surround if desired. Please see the each unit’s Installation Manual for more details.

  • Can I remove the glass from the Direct Vent Fire Ribbon?

    The glass can be removed for cleaning purposes, but must be firmly in place when the unit is in operation.

  • What types of fuel can be used with your products?

    Our products are designed and certified to run on propane or natural gas. You will need to provide your preference when you place your order

  • Are your fireplaces energy-efficient?

    Yes, between 80 and 95 percent depending on the model

  • Can I replace my fake log set?

    You have several options. Our Linear Burner System easily works as a retrofit system. Most people choose the smaller Linear Burner System to fit into their existing masonry fireplace, while others create a wood-burning environment and use the linear burner system as a customization.  See Linear Burner Overview for more info.  And finally some customers opt to remove their existing fireplace and go with a Direct Vent or Vent-Free unit instead

  • Can I bring the surround material to the edge of the firebox?

    Yes, Direct Vent and Vent-Free units are designed to have noncombustible surround material wrap to the opening of the firebox, (however a 1/4″ reveal must be left around the firebox opening). This maximizes its unique rectangular shape.

  • Where do I get the surround?

    We currently do not sell surrounds (although the Slim 46 includes a surround available in either Stainless Steel or Satin Black). They are a design element specified by an architect or designer.

  • Can any of your products be used outdoors?

    Yes. The Linear Burner System Outdoor, the Fire Ribbon Outdoor and the CUBE can all be used in any outdoor environment. All of our other products are approved for indoor use only.

  • Who can install my Spark fireplace?

    A gas fireplace installer or licensed HVAC contractor with similar experience is required for installation. Failure to use a certified professional may void the warranty. If you are having trouble, we might have resources that can help. Please contact us at 203-791-2725.

  • Where are your products approved?

    Please visit our certifications page for more information.

  • Are your products UL approved?

    All of our products are certified to industry standard ANSI and CSA codes. We use OMNI test labs, which specializes in the certification of gas products. UL is a certifying agency, equivalent to OMNI. OMNI tests our products to the same codes as UL listed products. OMNI is approved by all 50 states and all local municipalities in the US and all territories and Provinces in Canada. For additional information, visit our certifications page

  • What kind of pipe do I need to order?

    Our Direct Vent fireplaces work with M&G Duravent DirectVent Pro, 4″x 6 5/8″ pipe except for the Slim 46, DV 48 and the DV 19 that require the 5” x 8” pipe. Please visit the Duravent dealer locator web page for more information.

  • Why is the Elevation where I live important?

    Vent Free units

    At elevations higher than 4500 feet, the air is thinner and does not allow the oxygen depletion sensor to work properly.
    This faulty ODS reading will automatically shut down the pilot.


    Direct Vent units

    In the USA the appliance must be de-rated 4% for every 1,000ft above 4,500ft elevations (this is done at the factory so must be specified when ordered).  In Canada these appliances are certified for altitudes of 0-4,500ft.


    Linear Burner System:

    Linear Burner units are de-rated if needed on a case by case basis on any linear burners over 4500 ft. (this is done at the factory so elevation must be specified when ordered)

  • How does an ODS work on the Vent Free fireplaces?

    An Oxygen Depletion Sensor (ODS) pilot system reacts to a decrease in a room’s oxygen supply in a manner that shuts off the gas supply to the appliance. The gas pilot burns normally when it is exposed to normal air (20.9 percent oxygen). In the rare case when the oxygen level in a room starts to drop to an 18 – 18.5 percent level, the pilot flame lifts off of the thermocouple, which causes the gas valve to close. In other words, it shuts off the gas supply and “fails safe.” This unit was introduced to the U.S. in 1980 – 1981. All ANSI certified vent-free gas products incorporate an ODS. Based upon data available from manufacturers of the ODS, manufacturers of vent-free gas appliances and data available via legal databases, there are no documented deaths associated with emissions from vent-free gas products that incorporate an ODS. This data covers a 20-year history during which more than eight million units were sold in the U.S.

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