jjeff said:
^^^ correct me if I'm wrong but doesn't engaging any form of defrost(even partial defrost) disable recirc and even partial recirc? I'm pretty sure if you have recirc engaged and push the mode button to anything that shows air going to the windshield, it reverts to 100% fresh air.
Also while I agree with running fan at min speed while any form of fresh air is active, if I'm using 100% recirc(as I do for morning warmup in bitter cold) I find I get more heat by using a medium fan setting and since I'm set to 100% recirc or no fresh air, the air in the car just gets warmer and warmer. Using a low fan or any fresh air during morning warmup results in a barely warm car(at least when in the teens or below zero F).
It doesn't in my car. I will recheck that. You can hear flaps moving, even between fresh/partial/recirc mode. Except defrost button (not mode).
Full recirculation is the most energy efficient mode but that will result in fogging up if anybody inside the vehicle is breathing
With full recirculation mode higher fan speed does add to efficiency (only if vehicle is equipped with heat pump).
It is important to monitor heat pump and PTC element activation with LeafSpy. With high temp settings or high fan speed
PTC might start consuming a lot which is less efficient than heatpump.
Heatpump is also more efficient at higher driving speeds. It is also limited to ~50% during standstill.
You should warm up your car with preheat (still plugged in), not when you are in the vehicle but before.
Preheat uses full recirculation with some fresh cycles once in a while.
For rapid vehicle heatup period full recirc is acceptable until moisture starts to condense. With very cold weather (-10C and less) there is not a lot of moisture and this can be done for much longer. Still minimal temperature setting is recommeded for economy.
Heat pump is capable to draw 2kW for long period during driving and high fan speed. This results up to 7kW of heat, depending on outside temperature.