Just got a new ES350, and am wondering how to use the ventilation system without activating the A/C.
Thanks.

 

Model year 22 and prior - enable CLIMATE on the screen and deselect AC radio button. MY 2023 - I have no idea

 

Change with Techstream from AC Auto to AC manual. It will come on only when you turn on windshield deffoger or when you turn on automatic recirc.

 

Its pretty much the same as prior model years' operation as mikemu30 mentioned but with a small change in accessing the "Climate" section controls. From pages 258 and 259 of the LEXUS 2023 ES250, ES350 OWNER'S MANUAL:

Although she doesn't explicitly discuss the A/C control button, Northside Lexus's Melissa O'Connell in her "2023 Lexus ES Full Tutorial - Deep Dive" video starting at the 1:57:40 timemark has a pretty good explanation of the climate controls with the new ES Lexus Interface system:

 

Or you can just do what I do and ignore it. I set the desired temp and let the car handle the rest. I have been doing this since my 2015 ES and it hasn’t caused me any problems or concerns. I think automotive AC systems are much sturdier than they were a few decades ago. Just my opinion.

 

Agreed - I drive in AUTO always and merely adjust the temp selection.