Which engine do you have?

If it's a diesel they have a special Webasto diesel fuelled heater which only runs when it's cold. It warms up the air conditioning much quicker and then turns off. There will be a small exhaust unit under the body below one of the front seats. On mine its under the passenger seat as mine is RHD.

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Me:
Current: 2011 E71 40D Vermilion Red/Beige Nappa

Wifey:
Current: 2012 R80 Countryman SDX Green/Cream