Well I find the performance of the air-con is much better on recycle,there is the rear vents to extract stale air out and on long trips with no other vehicle in front I switch to vent to open for a few minutes [or if someone lets on off
] but gee on a very hot day the air-con will be flat chat trying to cool that hot air quickly and if you are behind a bus or truck do you really want their exhaust JMHO
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