The aux ventilation is not meant to either heat the car nor cool it per se. The heat function only works as a temporary function after the car has been running. The heat comes from heat generated by the engine. For example, you have been driving around for awhile, stop to pop into a shop and you want to keep the car warm for a short period of time. That will work. Likewise, the cool function only serves to suck out hot air in the car and keep the temperature lower than if the interior were allowed to heat soak.

You cannot heat up the car as you are wanting nor cool it with a/c without the engine running.

Oh, :welcome:.

Someone feel free to correct me if my recollection is wrong.

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