TXRacer

With recirc off, you get (cold) ram-air into the heater and through the vents. While the S2k's heater is excellent, this isn't giving it much to work with.

With recirc on, the air is pulled from below the dash. Since the aerodynamics of the S2k are so good, the vast majority of the air in the passenger compartment remains there, especially below the waist. The same air effectively gets heated over and over, which means you'll be much warmer this way. Airflow is also higher since the air is hotter.

Yes, you've got a big hole at the top of the car, especially if the windows are down, but passengers stay measurably warmer with recirc on.

joe_s2k

Thanks for making me feel a little more normal. I do believe it's the Red/Black MY2000 S2000 that makes us do things like this.

I also use the RECIRC TOP-DOWN setting while driving topless in cold weather. It seems to work good enough for me.

swells65

Thanks TXRacer, good explanation of where the air flow is.

wanabe

what micron filter?
dont remember seeing that in the shop manual!!!
maybe i can clean up the smog in LA with that filter!

wanabe

hey scooby- it really does work!!
i had not tried it before, and always have the top down-
last night (about 40 degrees here in sunny so cal), i hit the recirulate button as you suggested. it was like getting another speed on the fan- and i even had to turn it down!!

Digger

I have always heard that the recirc should only be used briefly in situations where you were in stopped traffic and wanted to keep exhaust from the car in front of you from entering, or similar situation. I've read leaving the recirc setting engaged is dangerous because no fresh air is entering the car thus depriving the driver of oxygen after awhile.

Tonky

LOL.. I'm with you Digger, but the issue is whether or not to recirculate with the top down

scooby2

Maybe we need a new sticker on the dash, "WARNING: Prolonged use of RECIRC may lead to death due to the lack of oxygen."

My take so far is that using RECIRC gets you warmer heat at the expense of less air flow. I was curious as to what all your REAL world experiences were...

lvs2k

If the car were totally airtight, your concern would be warranted; however, since it's not, a lot of fresh air is still entering, don't you think?

Digger

Ohh......you didn't get the 007 submersible edition. My bad.