...

Gas Fire Pit Flame Height – How To Get a Good Flame

Exploring Fire Pit Gas Supply
Table of contents

 

Gas Fire Pit Flame Height

One of the most common questions we get from people is concerning their gas fire pit flame height.
The two most common variations of this question are;

  1.  “How do I ensure I get a good flame height?”
  2.  “Why is my flame height so puny?”

We always prefer hearing the first question, because it suggests the fire pit is at the planning stage and no equipment has yet been bought. This is good news, this means we get to help the client buy the most appropriate fire pit or fire pit kit. However, if it’s the second question then it is likely someone who has a disappointing set-up which may require further expense to fix.

Nine out of ten times poor flame height is directly related to the gas supply, as you will see.

Expectations – What is a reasonable gas fire pit flame height?

We would expect a minimum flame height of 6” at the center of your fire pit for a standard fire pit burner. Anything less than that, we would consider unacceptable. However, if it is being supplied with enough gas for its BTU rating, at the required pressure, then the fire pit flame height could be anything up to 12″ high.

Torpedo Burners from HPC with their remarkable nozzles may give you a flame of up to 22″, and Bullet Burners from The Outdoor Plus, up to an impressive 18″ flame.

Planning a Gas Fire Pit

Location

Your first decision will probably be where you will locate the gas fire pit in your backyard are you going to locate your gas pit. Unless you are connecting to a 20 lb Liquid Propane Portable Cylinder, the location, as you will soon see is highly relevant to the flame height you will be able to achieve.

If you are interested in more information on fire pit location, read our comprehensive post on fire pit safety

Fire pit design

Your second decision will be about the size, shape, and design of your fire pit, which leads to the size of the burner you will be installing. The size of the burner will have implications on your gas fire pit flame height!

So on to the all-important question.

Why is the location and design of a gas fire pit relevant to flame height?

All burners come with a BTU rating (British Thermal Unit), which for our purposes, tells us how much gas your burner is going to consume per hour.

Say your fire pit design calls for a 24” diameter round burner. If we take a look at a listing for a Standard 24″ Fire Pit Ring Burner we can see that it has a rating of 297,000 BTUs. In order for this burner to function correctly and safely it will require that enough gas be supplied, to the location of the fire pit, at the right pressure.

The distance of the fire pit from the gas source, the diameter of the gas pipes, and how many bends in the piping all have an effect on the pressure and volume of gas that is delivered. All of this affects gas fire pit flame height!

Just like a garden water hose, the further the end of the hose is from the tap, the less the water pressure water at the end of the hose. Too far away and the water will just dribble out. Which when we relate back to our gas example, means a very small and weak flame. 

We can increase the diameter of the hose, but ultimately it all boils down to the original pressure at the source and the distance it has to travel. This is why it is important to know exactly where you will be building your fire pit.

Things to consider to ensure a great gas fire pit flame height

If you are still in the design stages of your fire pit then we advise you to employ the services of a qualified gas technician to ensure that you install a properly sized gas pipe and to check whether your property has a sufficient gas supply to cope with the intended fire pit.

If necessary you can also apply to your gas provider to have your supply upgraded.

Take into account that you may be able to achieve better gas pressure at the fire pit end if you tap into the house network as close to the gas meter as possible. This is something you should discuss with your Gas Technician as it may have consequences for the house gas network.

What options are there to remedy a tiny flame in a fire pit?

Existing fire pit

If you are dissatisfied with the height of your outdoor gas fire pit flames, our first question to you would be ‘Have you ever had a reasonable flame height from the existing installation?’. If your answer is yes, then maybe the system just needs a little maintenance.

  • Remove the fire glass/lava rocks and have a look at the burner. If any of the gas holes appear to be clogged with debris, use a small pin or unbent paper clip to clean out the holes. Do not under any circumstances attempt to enlarge the gas holes.
  • Use compressed air to clean out the gas pipes and ensure there are no blockages. Put everything back in place and light her up.
  • If your fire pit has an electronic ignition system or flame-sensing ignition please follow the troubleshooting section of the fire pit manufacturer’s manual.

If the fire pit or any of the components is new or differently sized, then read on.

A new fire pit or new components – fire pit flame too low?

If you are getting a low flame from your fire pit burner you may not have enough gas pressure coming into the property (gas meter) and/or incorrect gas pipe sizing (diameter) for the distance the gas is required to travel to sufficiently fuel the BTU rating of your burner.

If the budget is not an issue, then either of the above can most likely be rectified. However, if upping your gas supply and installing new gas pipes is not an option then you will have to work with what is available to you.

Some people attempt to install a larger burner to try to increase the flame height hoping to resolve the issue. If our explanation above has made sense, you will see immediately that this will in fact reduce the flame height even more, as a larger burner will have a higher BTU rating and therefore demand even more gas.

It therefore stands to reason that the best solution is to consider a smaller burner, with a lower BTU rating. This can be disappointing for some as generally the lower the BTU rating, the smaller the diameter or length/width of the burner.

Flame Height and Your Gas Pit Conclusion

As you can see, it really does make a lot of sense to confer with a Gas Technician, before you purchase any equipment. That should avoid any disappointment. Choosing the size of the burner (BTU rating) knowing that you have the required pressure to fuel it will ensure you get good flame height, providing it is installed correctly. Deciding that you want a particular size burner, and then finding out you don’t have enough gas pressure can be an expensive mistake. 

Hopefully, the explanation above will allow you to have a more knowledgeable conversation with your Gas Technician and enable you to reach a viable solution.

Further Information

For further information on Gas Pipes read our post Gas Pipe Size for Fire Pits.

Below is a table showing Propane Cylinder Dimensions

Gas Bottle BTU Table

The dimensions presented above are approximate measurements of common-size propane cylinders found in service today. The measurements are not exact so contact your propane company or container manufacturer for precise cylinder dimensions.


The information above is courtesy of Propane 101