Check the ignition system. Turn the gas off, and test your ignition button to see if it creates a spark. If both the pressure regulator on the gas tank and the ignition system are running normally (meaning the pressure regulator is tracking and maintaining correct gas tank pressure, and the ignition system is sparking and lighting correctly), you can finish testing the grill by turning the gas back on and lighting the grill up as you normally would.
Grilling season is upon us, which means summer cookouts, burgers and barbecue, and long, warm nights in the yard. It also means it’s time to clean your grill. The same cooking process that makes those Instagram-perfect, flavorful char marks on your food produces carbon deposits on virtually every interior surface of your grill: the grates, flavorizing bars and burner tubes (on gas grills), and the firebox itself. Those carbon deposits aren’t just ugly; grease can stick to them and harbor bacteria, and carbon buildup can cause your grill to heat unevenly or prevent it from reaching full operating temperature, and burner tubes to fail.
Re-assemble all the parts you removed, taking care to fix the burner tubes back in place in proper position with the cotter pins or screws. Rub cast-iron grill grates with a light coating of vegetable oil. Finally, re-connect your propane tank and fire up the grill; let it heat for at least 15 minutes, then turn it off again. This will help burn off any residues from cleaning, season cast-iron grill grates, and serve as a check that you re-assembled everything properly.
If you happen to be using an older Weber grill, or any other type of barbeque grill that wasn't coated with porcelain enamel, you'll need to season it before using it for the first time and sometimes reseason after seasonal storage. For example, when using a gas barbeque for the first time, always season it unless the directions specify not to. The procedure is the same for charcoal grills as for gas grills since it's the cast iron grates you're seasoning, not the gas or charcoal component.
For metal and cast iron grill grates, coat lightly with a high temperature oil like Canola or Peanut oil – wipe off any excessive oil, install the grates and fire up the grill. Heat the grill on high and let it burn for ~30 mins. This will burn all the solvents and impurities off of the heating elements, grill grates, etc. Note that porcelain grates won’t need a coat of oil, but will benefit from the burn in process to remove any chemicals/impurities that were applied by the manufacturer.
There are a ton of different grill cleaning gizmos to choose from, but nothing can beat a long handled wire brush, a wire bottle-style brush, a five-gallon bucket, and some elbow grease. Avoid toxic cleaning formulas. They can impart an off taste to foods, and aren’t necessary: warm water and dish soap and a paste of vinegar and baking soda are all the cleaning power you need. If your grill has stainless steel exterior surfaces, a good stainless steel cleaner (or vinegar) imparts an extra shine. You’ll also need some durable gloves and a few disposable sponges and rags. Pick an overcast day; hot sun can make it hard to remove streaks from cleaners (plus, it’s cooler working weather).
Reassemble the grill, then turn it on to its highest temperature setting and close the hood. There may even be a cleaning level on your burner dials. After a few minutes, open the lid and scrape the grates vigorously with a non-bristle metal grill brush. One I particularly like is the $15 Grill Bristleless Scraper from Taylor. This brush has multiple surfaces and edges to attack and remove grime from grill grates. It even has a handy bottle opener.
Check the fuel lines for invisible openings. Create a mixture of soap and water. Make sure you stir the mixture around so it gets really sudsy. Then, use a paintbrush to brush the soapy mixture onto the fuel lines. Turn on the gas, and brush some more soapy water onto the gas lines. If any bubbles form on the gas lines, that indicates a gas leak. Immediately replace any fuel lines that exhibit signs of a gas leak.