there are some that have a natural gas fired mini-generator, which produces the electricity to power the heat pump side. used in places where nat gas is much cheaper than electricity rates. they're pretty expensive though.
Then there's the gas piggy back units, where there is a gas fired furnace for when it is cold. But then, I've never seen one, so that means they cannot exist.
Steve ;-)
And, designr ( the person who asked the question) hasn't been here to clarify anything.
$7650.
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