Why won't my gas grill get hot enough?

A gas grill that will not get hot enough is usually short of gas, short of air or both. Start with the cheap checks: gas in the cylinder, the valve opened slowly, a full 15-minute preheat with the lid down. Then look at the burner ports and the drip tray. If all of that is fine and the grill runs on natural gas or a fixed gas line, the cause is probably gas pressure, and that is a job for a licensed gas fitter.

The usual suspects, in order

Most heat complaints come from one of five things.

1. Not enough fuel. Lynx's troubleshooting page says: "If using a propane bottle, be sure there is gas in the bottle and the valve on the bottle is turned on."^[1] A cylinder that feels light, or a gauge near empty, explains a lot of weak grills.
2. A tripped regulator. The same page notes: "When you hook up gas for the first time, the valve has to be opened slowly in order to not trip the regulator."^[1] Opening the valve fast is the classic way to get a flame that never rises above a low blue line.
3. Clogged burner ports. The same page says "Burners must be clean in order for proper gas supply to ignite."^[1] Grease, ash and spider webs block the ports one at a time, so the grill loses heat gradually. See how to clean gas grill burners.
4. A dirty drip tray. Lynx warns: "Grease build-up on the drip tray obstructs the air flow and can cause a grease fire."^[1] It also says not to use foil or other items on the tray or grates to collect grease, because that may affect the grill's performance.^[1]
5. Skipping the preheat or grilling in the wind. Lynx says to preheat with all burners on high and the lid closed for 15 minutes, and that the lid thermometer should reach about 400 degrees in that time.^[1] On wind it says: "Windy conditions can divert the heat causing a delay in heating temperatures."^[1]

What to do, step by step

The short version of the checks follows. Do them with the grill cool and the gas off, except where a step says to light it. Never open or loosen a gas connection.

Check that the cylinder has fuel and that its valve is fully open. Close the valve, turn every knob off, then open the valve slowly. Light the grill with the lid open, confirm that every burner lights, then close the lid and run all burners on high for 15 minutes.

Look at the flames before you close the lid. Lynx describes the right flame as blue with yellow tips and stable at the lowest setting.^[1] A flame that is mostly yellow, lazy, or missing along part of the burner means blocked ports or a burner that is not seated. Clear the ports with a paperclip, wire or a 3/32 inch drill bit, never a toothpick,^[1] and make sure each burner sits on its hangers and is pulled all the way forward.^[1]

Last, look at the position of the grill. If the wind blows into the back, the heat is pushed toward the knobs and the cooking area suffers. Turn the grill so the breeze hits the side or front.

When the problem is gas pressure

If the cylinder is full, the burners are clean and the flames still look weak, the supply may be the issue. This is most common on natural gas grills and on propane grills fed by a fixed line.

Lynx says natural gas or hard-piped propane units may have improper incoming gas pressure, and that lines may be too long or undersized.^[1] It adds that "Longer distances and turns or tees in the line can reduce gas pressure at the grill."^[1] Two more mistakes show up on its checklist: a grill that was converted between propane and natural gas without changing both the regulator and the orifices, and a bottle-type regulator fitted to a hard-piped propane grill, which does not pass enough gas.^[1] A second gas appliance on the same line, such as a side burner, can double-regulate the supply too.^[1]

None of those can be fixed by looking at the grill. A manometer reading at the grill manifold and the inlet is what tells the story, and Lynx notes that a reading at the inlet alone is sometimes not enough to tell what is happening.^[1] That is work for an authorized servicer or a certified gas plumber.

A word on regulators

Do not remove or bypass the regulator to get more heat. Lynx's manual warns that a pressure regulator must be installed on all gas equipment and that removing it or failing to install it can result in fire and serious personal injury.^[2] If you suspect the regulator itself, replace it with the manufacturer's part.

Stop and call a pro if

• You smell gas or hear hissing. Columbia Gas of Virginia says to listen for a hissing or blowing sound and watch for a rotten-egg smell, and that propane is heavier than air, so a leak can collect in low spaces near the floor.^[3] Turn the knobs off, close the cylinder valve, keep away from anything that could spark, go outside and call 911.^[3]
• The grill runs on natural gas or a fixed propane line and is weak on every burner. That points to pressure or pipe size. In Virginia no individual may engage in work as a liquefied petroleum gas fitter or natural gas fitter provider without a licence,^[4] so hire a licensed gas fitter.
• The grill was recently converted between fuels. The regulator and the orifices both need to be right for the fuel.
• Flames are still yellow or uneven after cleaning, or a burner is cracked or rusted through. Replace burners with the manufacturer's part.
• Grease or fire damage sits behind the control panel.

Getting help in Virginia

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