How Do Gas Fireplaces Work? | Mountain Home Stove & Fireplace

how do fireplace work

Gas fireplaces have been a staple of homes for centuries and if you haven’t had one before, there’s a good chance you know someone who does. They provide heat safely and reliably.  There’s a movement away from non-electric home heating; many gas appliances will provide safe heat if the power goes out.  Not only are gas fireplaces incredibly popular, but with the end of the summer, we’re inching into the perfect season to use a gas fireplace.

While gas fireplaces are a great addition to a beautiful home, some people may not be aware of how a gas fireplace works.

Before we fully get into how a fireplace works, let’s get into the basics. A gas fireplace will operate on natural gas or liquefied petroleum (propane) gas. With natural gas, the pressure is at a 6” water column pressure. Liquefied petroleum gas is twice that. What this means is that the burner regulator and orifice are different when it comes to the two gases. Besides these differences, the two basics are similar. You wouldn’t even know the difference by flame appearance alone.

The Ins and Outs

In a gas fireplace, a half-inch (or a ⅜” gas supply) line is connected to a burner through a gas valve. The burner will either be made of ceramic material or it will be a tube style burner. The burner consists of a gas valve, a control board, and fittings. The gas valve is closed as a safety measure unless there is a call for heat. It controls fuel to a pilot assembly and the burner.

When there is a call for heat, either from a thermostat, on/off switch, or remote control, the valve opens up and supplies fuel to the ignition system. Depending on the type of ignition system – electronic or standing pilot – fuel may first go to a pilot assembly then once the pilot flame is established the valve allows fuel to the burner.  The burner has small holes in it that gas flows through, which ignites and creates the flames you enjoy.  In a standing pilot system, a small flame exists full time and the valve allows fuel to the burner upon a call for heat.

Unless heat from a pilot light is present, it is common for condensation to develop inside the glass when the fireplace is first lit; however, the condensation will quickly dissipate once the unit heats up.

What About the Logs?

When you think about traditional wood-burning fireplaces (which many gas fireplaces are designed to emulate), you think of logs crackling in a fire. However, in the modern heath industry, gas fireplaces offer many different “media” options. There are plenty of realistic-looking ceramic logs that glow when they’re heated. This way, you can keep the look of a traditional fireplace without needing actual wood logs. You can also use driftwood logs, colored glass beads, sharp-edged glass, pine cones, and more.

The Basics of a Firebox

So, let’s go over the firebox. Made out of steel, it’s designed and manufactured to exact specifications. You will see that the size and dimensions of the firebox will vary between manufacturers and styles. Traditional looking fireboxes are square, 24″-48″ wide and there are also more contemporary units more wide than high – 18″ tall and five to eight feet long.

Glass and Co-Axial Venting

The glass you find on most gas fireplaces is made out of ceramic material, which can withstand high temperatures. Fireplaces are also made with tempered glass, which does not transfer heat as effectively and is less expensive, but may be the right choice in a room that doesn’t need heat.

What is co-axial venting? It’s essentially a pipe within a pipe and is manufactured in a few sizes.  The point of co-axial venting is that the products of combustion flow upwards and out in the inner pipe; air required for combustion flows downward and into the firebox in the annular space between the pipes.  It is common to find “B-vent” style venting on older units that are at the end of their life.  This vent provides only an exit for the combustion products and combustion air comes from the room.  This becomes a real problem in a “tight” house with newer or replaced windows, weather-striping or bathroom and kitchen fans, as the appliance becomes starved for combustion air and won’t run properly.

Where Can You Install a Gas Fireplace?

While you may see gas fireplaces typically in living rooms, gas fireplaces can be installed anywhere as long as a gas supply line can be installed and the venting requirements are met. You can install them in an entry, bathroom, bedroom, kitchen, even the garage!

A gas fireplace is a wonderful addition to any room in the house – if you’ve always wanted one, but weren’t sure how to go about getting one, stop by the showroom or give us a call! We’d love to install your brand new gas fireplace safely and efficiently.

Send us a message!

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2620 S. Copper Frontage Rd Unit 6b, Steamboat Springs, CO 80487

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