Why is my op amp railing?
This kind of op-amp has a bias current that flows out of the input, so opening it will cause the output to go to about +22V.
If you connect a resistor (say 100K) from the pot wiper connection to ground you will affect the linearity slightly, but an open wiper will result in an output voltage of only a few mV typically (worst case could be maybe 50mV).
Linearity will be affected by 0.25% (slight droop at 50.0%).
C62 is a really bad idea and can cause oscillation. Put it across the power supply instead.