Whether you’re making a DIY fire pit or fire table, using individual elements or a complete, CSA-certified burner kit, the underlying requirements of a propane installation are all the same.
First, always have your gas connections made by a qualified and licensed gas installer. Working with gas is dangerous, so you want to be sure the installation is done according to local building codes and is safe to operate.
Ventilation
When designing your fire feature, the most important consideration is adequate ventilation for any enclosed areas where gas could possibly collect.
Keep in mind that propane is heavier than air. When planning the ventilation for your gas feature, you should locate it in the lowest portion of the enclosure. This allows any gas that drops to the bottom, to drain out of the enclosure.
IN ADDITION to vents, propane fire features are required to have one side of the enclosure completely open. Most DIYers eliminate the floor.
Think of propane as water. You wouldn’t want it to drain down and collect inside of your structure. So, always leave sufficient ventilation for it to escape. In fact, the safest design is to leave the bottom out of the main structure entirely and have it suspended a few inches above the ground with legs, wheels, or some other design element.
Install support inside to keep the propane tank off the ground and out of sight, but having vents placed low on the sides and a floor-less structure with several inches of open air below where the floor would be and the ground, allows propane to fall and safely dissipate outward from the bottom.
Air Mixer Is a Must-Have
Propane has a much higher carbon content than natural gas. This not only causes propane to be heavier; it can also result in a deposit of black soot when it’s burned. To help the propane burn cleaner and reduce the likelihood of unsightly residue on your fire glass, you need to add an air mixer to the bottom of your burner.
The air mixer is a piece of pipe with a venturi (the tapered tube that increases gas pressure) in the center to draw air into the gas. Adding air to the gas helps the gas burn more completely. Air mixers are sized according to Btu rating, so you’ll want to select the correct size of air mixer to match your burner pan.
Gas Fittings
Now for a quick primer on gas fitting standards. There are two types of fittings used for gas fire features. The two types cannot be connected directly together without a “coupling” to convert the fitting types.
One type of fitting used in many commercially made fire pits and barbecue grills is the flared fitting. These are easy to identify since they have a flared tip. This flared tip is what provides the seal for the gas.
YELLOW TEFLON tape is required for NPT fittings, but should NOT be used with flared fittings.
Since the flared tip is making the seal, the only purpose of the thread is to hold the flare tightly in place in order to retain the seal. Since the threads aren’t providing the seal, you should not use Teflon pipe tape when connecting flared fittings.
The other type of fitting is a tapered fitting called NPT – commonly known as National Pipe Tapered Thread, which is a standard for tapered threads. With NPT, the seal is provided directly by the threads. That means the tighter you screw the threads in place, the tighter the seal.
For NPT fittings, Teflon gas tape is always required. In the U.S. and Canada, Teflon gas tape is designated by the color yellow for easy identification.
If you’re measuring existing NPT sizes, you should know that the size is loosely based on the inside diameter of the pipe and not on the actual thread size. For example, the outside thread diameter for half-inch NPT measures just over three-quarters of an inch, which is the size used for most of our burners and components.
Burners
There are two types of burners most commonly used in fire features.
Burner rings provide a flexible option for many fire features from custom fire bowls suitable for a table to large projects such as a fire pit made with pavers.
DROP IN BURNER pans are the most popular choice for DIYers because they are the easiest to install.
Burner rings from Celestial Fire Glass are made from stainless steel tubing, with slightly inward-facing holes on the top. They can be installed upright or upside down, but for propane installations, they must always face up. This is because propane is heavier than air and needs a little push to rise through your fire glass or lava rocks up to the surface.
The second type of burner, which is the most popular and easiest to install, is the drop-in burner pan. Drop-in burner pans are the “go-to” choice for fire tables because they include the burner and a pan in one assembly. This makes installation a breeze.
Burner pans are installed by placing them into a cut-out in your tabletop that’s about an inch larger than the actual pan size (the part that sits below the surface). This provides an extra half-inch of spacing on all sides around the drop-in portion of the pan making it easy to place in the cutout. Plus, the extra space allows for some expansion and contraction during heating and cooling.
Drop-in burner pans are held in place by their own weight, so other than dropping it into place, there’s no other work required to mount the burner pan. The burner pan has a half-inch NPT male fitting on the bottom to connect to the gas supply line.
Gas Regulators
Propane fire pits require gas pressure of between 7 inches Water Column and 11 inches Water Column. Water column, commonly referred to as WC, is the amount of gas pressure required to raise water in a vertical tube at a given distance.
As a frame of reference, 28 inches WC is equal to 1 PSI (pounds per square inch). Therefore, 7 inches WC is one-quarter of one PSI, and 11 inches is slightly more.
The pressure required for a propane burner is higher than what is used for typical barbecue grills. This is because the grill only requires a small flame for cooking, while fire pits have a larger flame for display and heat.
Barbecue grills use a low-pressure regulator that meets the needs of the smaller flame. For a fire pit, you’ll need to use a high-pressure propane regulator to get the desired flame height. If the highest your flame will go is an inch or two, it’s most likely because you have a low-pressure barbecue grill regulator installed.
The Right Hose
There are several types of hoses used for gas appliances.
One type is a standard flex hose, which should be avoided. Standard flex hoses have evenly spaced ribs along their entire length. This even spacing causes an oscillation effect, which results in a high-pitched whistling sound. Not what you want to hear when you’re trying to relax by your fire pit!
A “whistle-free” flex hose features uneven rib spacing in order to prevent oscillation and whistling noise.
The most common type of hose is a standard rubber gas hose. These won’t whistle, since the inside is a smooth surface without any ribs. Rubber gas hoses typically come with most propane regulators and connection kits.
Lighting Up
To turn the gas on and control the flame height, you have two options with propane.
The first option is to use a high-pressure, adjustable regulator. It’s the easiest to install since it simply connects the propane tank directly to the burner. The gas is controlled by the knob on the regulator located by the propane tank. This is a suitable option if you have easy access to your propane tank to adjust the flame.
When connecting the regulator to the burner, be sure to add the appropriate-sized air mixer.
Celestial Fire Glass offers ignition kits that include the regulator, key valve, air mixer, and hoses needed to connect your burner to a propane tank. With this option, the key valve is installed in the cabinet under your fire table and is used to turn the gas on and adjust the flame height. No additional parts are needed to make your gas connection with this kit.
The easiest way to manually light your fire pit is with a butane stick lighter. Another option is to install a spark igniter. With this option, the igniter is located above the burner. Since propane is very heavy, it may pool in your burner pan before it gets high enough to ignite. When this happens, there is a large initial flame, which can be dangerous.
If having a spark igniter on your propane fire pit is important to you, we recommend going with a complete CSA-certified burner kit. These kits are CSA- certified for safety and include everything you need—burner pan, propane regulator, hoses, flame control knob, spark igniter, and thermocouple.
The thermocouple is a safety feature required in CSA-certified kits. The spark igniter and thermocouple are housed in a small box with holes on all sides. Inside, gas is directed at the spark igniter, which enables the flame to light as soon as the gas is turned on. If the thermocouple doesn’t sense the heat of the flame, it turns the gas off preventing a dangerous build-up of gas.
Give Us a Call
If you need help determining what parts you need or how to install them—or if you just want to troubleshoot a problem – give us a call. We’re happy to assist!
Our technical support team is based in Frederick, Maryland. They’re available by phone from 8 AM to 5 PM Eastern Time, Monday through Friday.