Hmm, I'm in the NorEast and don't like the sounds of that! But I never idle for that long, they never heat up properly like that, typically I let mine idle for not even 5 minutes in the driveway and then drive it easy for 5 minutes until the needle moves...The warm up time is horrible in cold climate like Canada. After 20 minutes of idle, barely any hot air is being pushed out. Even after driving 10 minutes it's horrible.
When the new thermostats fail they fail in the open mode that will give you a no or low heat situation.I am having the same problem with my trax not heating up. I drove it for about 20 minutes today, and my coolant temp was only up to about 150 degress. (Checked using "Torque" app on my cellphone. ) and it blows out lukewarm air. Granted, it is only about 5 degrees out this morning, but still, my other vehicles warm up ok. Why doesn't the trax? This is pretty annoying.