Ran the heater on full blast on a Summer day with a temp of 102, because running bumper to bumper in Spec Miatas we were all running hot, hot, hot. That was back when most of us had not purchased cool suits and we all came in looking like lobsters --- surprised no one got heat exhaustion but we had been drinking gallons of water.
Instructing with my helmet on, loud Mustang exhaust music in my ears, one does not always notice the AC is on, especially since it kicks out under full power, hence I plead the 5th. Tracy was fast, even with the AC on, and a driver awareness lesson was learned, heh,he!