Gas stove knobs are basically in-line shut-off valves. A knob that becomes stuck in the open or "on" position continually releases fuel and presents serious danger. If your gas stove knob is stuck in an open position, immediately cut off the gas supply to the appliance and repair the knob before using the stove. Dedicated supply valves are located beneath or behind stoves. If you have trouble finding the stove's valve, shut off the gas at the home's main supply valve.
Shutting Off the Gas
Pull the stove away from the wall. Look behind the stove to locate a gas shut-off valve. Shut-off valves usually have a single, straight handle, often yellow or red.
Rotate the handle to the "off" position, usually perpendicular to the valve's body. If you cannot determine which way to turn the handle, inspect the handle or body of the valve for text or arrows that indicate the "off" position.
Search for the home's main supply valve if you can't find the stove's dedicated supply valve. Look for the main valve within utility closets or around the perimeter of the home's exterior wall. Grab the main supply valve's handle with a rag and rotate the valve to the "off" position.
Replacing a Stove Knob
Loop your index and middle fingers behind the broken knob. Press your thumb over the exposed face of the knob.
Pull the knob away from the stove's surface. Slide the knob off of the peg that protrudes from the stove.
Align the hole on the replacement knob's rear with the peg that protrudes from the stove's surface. Press the replacement knob onto the peg.