New-for-me 2014 L&K diesel with aux heater installed. 

 

When is it recommended to use the auxiliary heating? Manual doesn't suggest a temperature. 

 

I reason that a warm engine from the start is better than a cold one. With that logic should I use the aux heat before every drive regardless of outside temperature to ensure a warm engine before driving?

 

How am I to interpret this from the manual?

Quote

Auxiliary ventilation

The auxiliary ventilation enables fresh air to flow into the vehicle interior by switching off the engine, whereby the interior temperature is effectively de- creased (e.g. with the vehicle parked in the sun).

1

 

Is the ventilation activated by turning on the aux heat when it is above the set temperature on the control panel? 

Do not confuse auxiliary heating with auxiliary ventilation.

The first heats the car by burning some fuel and circulating it, the second uses a solar panel on a small sunroof to ventilate fresh air when parked in direct sun.

 

With regard to when you should use the heating, I would say whenever you don't want to get into a cold car.

Modern oils are supposed to be designed for cold starts.

 

Prepare for decent advice from those who know what they are talking about though