It's simple. In the garage, hang a 3" flexible pipe from the ceiling that connects directly into your home's HVAC system. Then leave your car window part way down and stick the pipe in the crack. Now your car will be the temperature of the inside of your house when you get in the next morning. It's eco friendly because heating or cooling just the car through a small pipe is much easier than the whole garage.

Note this is NOT an engine block heater, it is for the passenger compartment.
-- DIYMatt, Dec 11 2009

You'll need flow and return pipes, a booster blower, and some way to seal the rest of the gap round the window, but very Bakeable.
-- 8th of 7, Dec 11 2009


sure [+] just remember that you've got to heat up not only the air in the car but the upholstery, dashboard, etc.
-- FlyingToaster, Dec 11 2009


You certainly wouldn't want to run this continually as your heat losses through the car into the garage would send your bill into the stratosphere in the winter time. Perhaps you have a regular schedule and can heat up the car 30 minutes before you're to leave for work. Or you can set a timer if you'll be driving on winter holiday to warm up the car a preset time before you depart.

Put a timer and/or a user set switch on and I'll give you a pre-warmed croissant.
-- bdag, Dec 11 2009


If you're going to do that, just put a fan heater on a timer inside the car, run the cable out to a timeclock in a nearby outlet, and it's done.

Presumably the original idea was to use low-grade heat recovered from the building to warm the car, thus saving energy.
-- 8th of 7, Dec 11 2009


Nicely done. Just make sure that the pipe isn’t long enough to reach the exhaust …don’t want those disgruntled suburban teenagers taking out the whole family in the dead of winter…
-- scootie, Dec 16 2009


// the dead of winter //

[marked-for-movie-title]
-- 8th of 7, Dec 17 2009



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