When they invented the infrared grill forty years ago, TEC Grills was in a league of its own. No other grill could get as hot as theirs for that perfect sear. But people grill more than steaks and burgers, so their engineers went back to the drawing board to fine tune their burners. Today, they’re in a league of our own for the opposite reason: no other infrared grill on the market is capable of turning down to an ultra-low 200°, the perfect temp for slow cooking a pork shoulder or smoking ribs. And they still hit that high high that drew you to infrared in the first place.

Gas Grill Repair

The Tank  
Modern propane tanks, mandated by the government, contain an Over Fill Prevention (OPD) Device. This makes it so a propane tank cannot be overfilled. Rarely, the OPD on your propane tank can be damaged causing the tank to work incorrectly. 

Fuel Hose and Regulator  
The output of a propane tank or your natural gas line is much greater than you need for grilling. The regulator controls the amount of fuel that can flow to your grill. This attaches to the tank (or natural gas line) with a flexible hose with an O-ring to create an airtight seal. Regulators are preset by the manufacturer and should not be adjusted by you. If you look at your regulator you will notice a small vent hole in the center. Common problems are clogged vent holes, which can cause irregular fuel flow and can lead to trouble. Usually, you can clear it by tapping or blowing into the vent. Other problems are fuel leakage caused by a worn or damaged hose or O-ring. To determine if there is leaking mix dish soap and water in equal parts and coat everything from the tank to the control valves with the mixture and see if it produces any bubbles. The tank needs to be connected and on but the control valves off. If you find a leak, replace that part. 

Control Valves 
The controls valves regulate the flow of fuel to the burner. Each burner on your grill has a control valve. You cannot repair a bad control valve and if need be, you should replace the whole unit. Before you do, however, remove the control valve from your grill and inspect it. Like other parts of your grill, insects love to climb in here to nest. At the center of the control is the orifice. The orifice controls the flow of fuel and can become clogged. If it is, use a thin wire to clean out. Make sure you put it all back together the way you found it. Without the orifice, you cannot regulate the amount of gas flowing to the burner and run the risk of explosion. 

Venturi Tubes 
The venturi tubes connect the control valve to the burner(s) and mix the fuel with air to provide the flame. To do this, there is an open gap in the fuel line that can easily become obstructed. Insects, especially spiders, commonly nest here. The best solution for this is to wrap the venturi tubes with an aluminum screen that will not block the airflow but will keep the critters out. Many grills come with protected venturi tubes. Another common problem is a misalignment of the venturi tubes with the burner. Typically the venturi tubes are simply placed in the fuel line and can get knocked out of place. The venturi tubes have adjustable shutters and they may need an adjustment to regulate fuel flow. 

Burners 
Burners come in many shapes, sizes, and materials. Burners range from aluminized steel at the low-end to cast brass and stainless steel on the high end. Low-end burners will typically last about three years under normal circumstances. Because the burner is inside the grill, it tends to get coated in burnt grease and can corrode quickly. Inspect and clean your burner regularly to avoid problems. If the burner is damaged or too heavily corroded, you will need to replace it. Get the same size and shape of the burner but consider purchasing one of a better quality metal if possible. 

Barrier or Radiant 
In between the burner and the cooking grate is a barrier, also called a radiant. It is supposed to absorb and release heat evenly to the cooking surface. The barrier protects the burners from drippings and creates a place for grease to collect and burn off. It may be constructed of lava rocks, ceramic briquettes, or metal plates. These need to be replaced periodically as they become crusted with burnt grease and food; this can eventually create an unpleasant flavor on foods. Porous lava rocks tend to need replacement more often. Metal plates can typically be cleaned and used for a longer time. Inspect your barrier. If it is broken up, heavily coated, or simply not creating a sufficient barrier, consider replacing it.

SOURCE: thespruceeats.com