Efficient ventilation mode?

Yes it might. Try it and see.

Do you have an owners manual ??

 

In the Repair Manual, available by subscription to toyota-tech.eu, under Air Conditioning System: Customize Parameters, Toyota writes that “Efficient ventilation mode” is a “Function to change the mode automatically to recirculation air mode when turning the A/C on to cool the cabin quickly.” The default setting is “On.”

 

Looks like a nice feature! I would guess that it has something to do with using outside air if the inside air is hotter than the outside air.Then, when the inside air temperature get down to the outside air temperature, it would switch to recirc. Probably also has to do with fan and compressor speeds.

 

WOW. That is amazing......and troubling, since being in the recirc mode can suddenly fog over your windshield and block your view under some conditions. I would think that the default should be OFF........since having the AC start up in "fresh air" mode is just a minor inconvenience and not a safety hazard.

 

AFAIK, the A/C will chill and dry recirculated air exactly the same as fresh air. Because the internal air is the same temperature as the windscreen it should not fog up for very long unless you've sat in the car for a while before starting the system.

 

That sounds logical but it is WRONG much of the time.
You can't appreciate the difference unless you have seen it.

As the outside temperature goes down, the absolute humidity goes down too; cold air is dry.
The air INSIDE the car has no way to "expel" it's moisture as the temperature drops and the absolute humidity goes WAY up.
Sometimes all of the interior surfaces are slightly damp; add in the moisture from your breath.

Note that when you turn ON the front defroster, it automatically turns OFF the recirc.

 

I think it should be ok, for a couple of reasons:

1. AC tends to dry the air very efficiently.
2. If I'm not mistaken, the cabin air temperature sensor also is monitoring humidity, and the ventilation system's logic might switch to outside air if there was high humidity? Maybe @Elektroingenieur knows?

Personally, I leave AC off as much as possible. I'll use it in heavy rain, when there's no other way to keep the windshield clear, but that's about it. By "AC" I'm referring to the active cooling system, the North American meaning of AC, not the fan system as a whole (as Toyota refers to it).

 

Only saying what happens in the Gen 4 hatchback and feel qualified to comment on that.
Unlike some posters.

 

Indeed.

Sorry you have such limited experience.

Having worked for a rental car company for quite a few years, I've driven maybe a HUNDRED different models or more and in this respect they are all pretty much the same.

And they have been the same for about 40 years, since A/C became a pretty standard feature.

 

Just ignore him. I do not know why he made a second account to ignore.

 

Definitely - Recirc+A/C = drier air - then add heat to comfort level.

The evaporator of the A/C, condenses water vapour, it drips down the evaporator, along the water channels and drains TO OUTSIDE.

If you open outside vents, you just invite more moist air inside.

We lived in the mould capital of Queensland which was on a mountain range surrounded by rainforest, most nights were foggy, and fogged up windscreens were a constant battle - till we got A/C.

 

I think the confusion here is over the context of the word "efficient". "Efficient ventilation mode" is not referring to it being great at ventilating your car, it's referring to its fuel efficiency. This is the same as the Eco control on the climate control on other cars.

It turns re-circulation on because that is the most fuel efficient way of cooling the cabin, as the AC only needs to cool the volume of air within the cabin, which it can do quickly, and then maintain it at that temperature. With re-circulation off, it would have to continuously cool the incoming outside air down to the required temperature, which obviously requires more energy.

If you want to keep your windows clear, you need to have re-circulation off (so the moist air can escape the cabin), and the AC on (which dries the air due to moisture condensing on the cooling elements), and have the air direction controls set to direct the air flow to the windscreen, along with the fan at a moderate to high speed.

 

In mine, the Auto button cycles through three HVAC modes... Fast, Normal and Eco. True, the button is simply marked Auto, but the full automatic range is still there. Incidentally, further to what @Prodigyplace said elsewhere, when I select Evo Drive Mode the HVAC is set to Echo at the same time. This will be of purely academic interest to you guys more than 10° West of the Greenwich Meridian.

As for Sam, well.... I live in hope. I've know many officer cadets so bloated with their self importance and adamant in their preconceptions they refused to accept the correct training and avoid following instruction. You must never give up on them. To do so is to fail yourself, so I'll not block him.

 

You must have different setup to us -


Yours is mirror imaged, though not totally, has more thingys in the display (dual climate control?). But your AUTO button appears to have multiple toggle functions

 

In the US we have an Eco button. It does not have an LED indicator like the others around it though. the only indication is the word ECO beside the fan speed indicator. For us, at least an LED would make sense for a quick check at a glance.