There are many people who have access to natural gas supplies and have grown weary of continuously having to purchase expensive propane gas at the store. Many have also wondered if it is even possible to convert a propane grill to their natural gas supply.
Well then, let me tell you that this conversion is not only possible, it is quick and easy for the average home owner to accomplish. As a note here, doing this conversion will void any warrantees that your grill may have had from the manufacturer. This information is provided as a guide only, in no way do we claim fault or liability. Now, on with the job.
The first thing you need to consider: is the grill in good enough shape to even put the effort into converting. Are the burners in good shape? Is the grill damaged or bent? Do the doors and hinges close properly? If you have any doubts about your grill, it is recommended that you purchase a new one or possibly find a used one at a yard sale before doing the conversion.
Now you will need to decide where you want to tee off from your existing gas line. Try to avoid teeing off by the meter and running a lot of line to your grill. If possible, tee off from the closest line you have available to where your grill is going to be used.
IMPORTANT NOTE: SHUT OFF YOUR GAS AT THE METER BEFORE PROCEEDING ANY FURTHER WITH THIS PROJECT.
Next, disconnect the gas line and add a tee in the line if it possible to do there. If not, you will need to cut the line in order to fit your tee in place, making sure you have purchased a tee with it’s own shut off valve. Make sure you have sealed all connections with the appropriate type sealant that is approved for use with natural gas.
Attach your piping to the end of this valve and continue running to where you want to have your grill placed. If your line is under your house and away from hazard, then a plastic or flexible line is acceptable for this purpose. Although flexible line is more expensive than rigid plastic or metal, it is a lot easier to get around obstacles that might be in your way. Where the pipe comes out from a protected area, switch to a rigid type to protect it from incidental damage. When you get the pipe to where the grill is going to be set up, install another shut off valve there, making sure that it is closed.
Now check all the connections you have made. Turn your gas back on (remembering to make sure your last valve by the grill set up area is closed) and using soapy water and a sponge, dribble a bit of the water mixture over the joined area. If there is a leak, it will show by making bubbles appear where the leak is located. If a leak is detected, tighten the affected joint until no more bubbles appear.
Now it is time to convert the grill proper. Remove the LP gas regulator from the grill. The regulator that is attached to your incoming gas line going into the house will do this job for the grill too.
Leave the existing hose from the regulator to the burners if it is in good condition. This hose will be used later to attach the grill to your incoming supply line you have just installed.
Now it gets a bit trickier. The orifices that help regulate the flow of propane gas are smaller in diameter than what is needed for natural gas. These orifices are found in the control knob assembly used to adjust your flame levels. These orifices and knobs are attached to the burners often with tubes that slide into the burner assembly which can be removed by simply pulling them out of the sleeves attached to the burner.
An easy way to do this on most grills is to remove the entire front assembly that holds the knobs by taking out the four screws on either side and pulling the entire piece forward.
With the orifices exposed (they are on the tips of the tubes that poked into the burner assembly), you will notice two small holes on the very ends, these are the burner orifices. Using a drill, drill out the smaller holes to a larger diameter, often a one sixteenth drill bit is sufficient to get the diameter you need. Remember, if you find that later your grill runs too low, you can always remove the control knob assembly and re-drill the orifices to a larger size.
The last step, after reattaching your control knobs and burner assembly, is to connect your grill to your natural gas line. Often your line from the propane tank will be too short to accomplish this separately. You can use a flexible, metal gas line or a black plastic line here to do this job.
Using the appropriate sized and style of fittings, attach one end of this line to the shut off valve you installed previously, and the other end to the grill. If you have to install this line into an existing plastic or rubber line in the grill, ensure you use a barbed fitting and two hose clamps on both ends to secure this connection properly.
Now your grill is ready for a test run. Light your grill as you would when igniting a propane tank, and adjust your flame accordingly. If it runs high enough and has a steady blue flame then your conversion project has been a success. If it runs too low, you may need to re-drill the orifice holes to a larger diameter. Close the lid and let it run for ten minutes to insure all fittings and junctions remain secure after heating. If everything is all good, its time to throw on your favorite grill item and enjoy.