Clean an outdoor gas grill by wiping down the outside of the grill, brushing the grill grates and cook box with a steel brush or grill stone, and washing the venturi tubes with soapy water. Carefully reassemble the grill and re-establish all connections after cleaning.
To clean the exterior of your gas grill, use paper towels and glass cleaning spray for a porcelain-coated grill, a microfiber towel and stainless steel cleaner for a stainless steel grill, or water and dish detergent for a powder-coated steel grill. Remove excess food and built-up grease from grill grates by scrubbing with a steel wire brush or grill stone. When the grill grates are clean, coat them with cooking oil to prevent further build-up.
To clean the cook box of your gas grill, remove all of the grates and bars before brushing all sides with a steel brush. Discard any debris that comes loose. Clean the venturi tubes with water and dish detergent. Use a steel brush or bit of wire to unclog the holes on the venturi tubes. Rinse the tubes with a hose and dry completely before re-attaching.
When re-assembling your gas grill after cleaning, make sure the fuel line is free of cracks and that the connections are tight. Check that the venturi tubes properly align with the gas valve. You can use the regular cleaning of your gas grill as an opportunity to check the propane level and check the ignition system for proper sparks.