Enum value stuck in SmartApp

I was looking at the source code for SmartThings’ Virtual Thermostat app (https://github.com/SmartThingsCommunity/SmartThingsPublic/blob/master/smartapps/smartthings/virtual-thermostat.src/virtual-thermostat.groovy).

I put it in the simulator and was playing around with it. I added some debug statements in the Evaluate method to print the mode and I noticed that no matter what I select the mode is always stuck on heating.

This is my code: https://github.com/kshenoy/SmartThings/blob/master/smartapps/kshenoy/virtual-thermostat.src/virtual-thermostat.groovy

Can someone please help me figure out what I’m missing here?

Thanks