Troubleshooting a Weak Flame on a Gas Grill

If you are experiencing a weak flame from your gas grill, try these troubleshooting tips before refilling the tank.

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We’ve occasionally fired up our gas grills only to have the burners emit a low flame, no matter how high we set the knobs. 

While this could mean it’s time to get a new tank of gas—it could also indicate that there’s a problem with your grill.

There are three primary suspects when your gas grill has a low flame. Luckily, all are easily addressed:

  1. A tripped regulator

  2. Not much propane left in the tank

  3. Spiders in your gas lines

Here’s how to diagnose the problem and address each of these issues.

How to Reset Your Gas Grill’s Regulator

A weak flame is often a signal that the safety regulator on the propane line—that aluminum device that sits near the end of the hose that attaches to the tank—has been tripped, slowing the flow of gas to a trickle.

The regulator has two main functions: It keeps the gas pressure at a safe level, and it's designed to respond to low pressure inside the hose, a sign that there’s a leak. However, it can also be tripped accidentally if you turn on the grill burners before you open the valve on the tank. 

With the burner valves open, pressure never builds up inside the hose, and the regulator thinks it has detected a leak.

To avoid the problem, always make sure to open the valve on the tank before turning on the grill’s burners. And when you have finished grilling, be sure to turn off the burners before shutting off the gas flow from the tank.

If you forget the order of operations above, follow the steps below to reset the regulator and get your grill back up and running.

1. Turn off all burners.

2. Turn off valve on tank.

3. Detach regulator and hose from tank’s nozzle; wait at least 30 seconds before reattaching it.

How to Check Your Propane Level

Your grill’s flame might be weak simply because it’s running out of fuel. To check if you need a new propane tank, you can employ a couple of different methods:

  1. Easiest option: Rap on the side of the tank. The point where the sound changes from a thump to an echo indicates the level of the fuel. This method is easy but somewhat unreliable.

  2. Best option: Pour hot water down the side of the tank. The empty portion of the tank will feel warm to the touch, while the full portion of the tank will stay cool. This method, which you can read more about here, is much more accurate.

How to Check for and Remove Spiders from Gas Lines

If you find that your propane level is high, but that your grill’s flame is low, there may be some unwelcome visitors hiding in your gas lines. Spiders are known for building nests and laying eggs in grills’ burners and venturi tubes (the tubes that extend from the burner to the control valves), obstructing the flow of gas.

To prevent this, you should always remove and clean your burner and venturi tubes after the grill has been idle for a long time.

Many grills include long, thin metal brushes that you can use to clear the tubes.

Now That Your Grill Is Up and Running...

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