Great idea
I vote for a switch, just in case...
Luckily my car has a switch to engage/disengage the compressor while directing air to the defrost vents.
When the car is parked outside for a few days, I like having the option -- if a bunch of snow gets in, starts to melt, and fogs up the works and just breathing does it too.
More on the reason: the extended parking situation (airport) offers no outlet for the block heater, so it takes a loooong time to heat up. I'd crack the window to let the dry air fix the situation, but the combination of continuing to freeze my arse, not letting the temp get up to allow TC lockup, and robbing the engine's heat is the 3rd strike. Even with a winter grille block, it's tough to get that heat. I hit the highway immediately in this case.
The worst situation last Winter: scraping a 1/2" layer of ice off of the glass, the temp dropped to the teens so it was freezing, and I don't idle the car to warm it up.
I'm sure there's a solution -- any thoughts? (other than being tougher in the cold -- I know
)
RH77