The indicator lights blink 3 times, which says that the centrifugal switch is stuck open. I have located the centrifugal switch, and with power off, have gently tapped to free, which apparently has not worked. This is an Evcon propane gas furnace. I have the thermostat all the way up, power is currently turned off.
What do I do next?

The centrifical switch should be part of the motor. What's the model number of the furnace?

The DGAH model