the plastic knobs on my blackstone get so hot during use i can't touch them to adjust.

Diagnosis

The overheating of the plastic control knobs on the Blackstone 28-inch Griddle with Air Fryer is caused by thermal conduction. The metal valve stems, which connect the burner valves to the external knobs, act as heat sinks. Because the burners are positioned directly behind the control panel, the intense heat from the burners—especially when running at high temperatures for searing—travels up the metal spindle. The factory-installed plastic knobs are made of a high-temperature polymer, but they lack a thermal break. When the metal spindle reaches a critical temperature, it transfers that heat directly into the center of the plastic knob. This is often exacerbated if you have the air fryer attachment running simultaneously, as it creates a concentrated heat zone that can radiate back toward the control panel, overheating the valve assemblies faster than they can cool via ambient air.

How to Fix It

To resolve this, you need to create a physical thermal barrier between the heat source and the knob. The most effective method is installing high-temperature silicone or stainless steel spacers.

1. Turn off all burners and allow the griddle to cool completely for at least 60 minutes. Attempting this while the metal is hot will result in burns.
2. Carefully pull the plastic knobs straight off the metal spindles. Do not twist them aggressively, as you can strip the internal plastic gearing.
3. Inspect the spindle for any carbon buildup or grease. Clean the stem with a small piece of steel wool or a scotch-brite pad to ensure a flush fit for the spacer.
4. Slide a 1/8-inch thick high-temperature silicone washer or a stainless steel heat shield washer over the spindle, seating it firmly against the control panel face.
5. Press the plastic knob back over the washer and onto the spindle. This creates a small gap (approximately 3-5mm) between the control panel and the knob, allowing air to circulate and preventing the knob from absorbing direct heat from the panel surface.
6. Test the griddle by lighting the burners and monitoring the knob temperature with an infrared thermometer; you should see a temperature drop of 20-40 degrees Fahrenheit on the knob surface.

If That Didn't Work

• Replace Knobs with Metal Aftermarket Versions: If the plastic continues to warp or soften, replace the factory knobs with heavy-duty stainless steel or cast aluminum knobs. These have higher thermal mass and do not melt or deform, though they may still get hot, they will not degrade like the plastic ones.
• Install a Rear Heat Shield: Fabricate or purchase a thin sheet of reflective aluminum or stainless steel to mount behind the control panel. This deflects the radiant heat from the burners away from the valve stems and back toward the cooking surface.
• Adjust Burner Height: Check if the burner tubes have shifted. If a burner tube has slid too close to the control valve assembly, it will overheat the spindle. Ensure the burner is centered and seated properly in its brackets.
• Use Heat-Resistant Grips: Apply a small wrap of high-temperature silicone tape (rated for 500°F+) around the base of the spindle before installing the knob to act as a gasket and insulator.

Heads Up

• Avoid using "high heat" for extended periods if you aren't actively searing; keeping the burners on medium-high reduces the thermal load on the valve stems.
• Never use metal pliers to turn the knobs if they are too hot, as this will crack the plastic housing and ruin the valve connection.
• Periodically check the knobs for "melting" or softening. If the plastic becomes tacky, the integrity of the knob is compromised and it must be replaced to avoid it falling off during use.
• Keep the area around the control panel clear of grease buildup, as accumulated oil can act as an insulator that traps heat against the metal spindles.