External rad over AC vent (condensation?)

**Edit** Update. It work fantastically! Made sure running identical pump flow rate 140-145L/H on the aqua computer flow sensor (trust worthy). The longer loop did require me to push one D5 up roughly 8% to hit that rate.

Identical load and heat soak… waited 1 hour. Dropped GPU hotspot temp by 14c.

Idle water temp was 17.1c and GPU idle was 20c.

With AC entirely off and let the heat soak occur again for 30 mins… dropped 2-4c depending on load from the GPU hotspot so adding that amount of liquid volume plus another small rad definitely added to the cooling.

**Original Post** I’ve seen others do this in the past with the warning from others about condensation without a lot of heat input.

Maybe I’m not grasping where the condensation builds up… What would be the worry about a exterior radiator setup in a floor duct AC unit that fed into a system with 2 (240mm and 360mm) existing rads and 2x D5 pumps?

Condensation build ups should only occur on the outside of the third rad within the vent and that wouldn’t affect the PC a short distance away.

Unless I don’t know how the coolant (Mayhem X1 Eco) reacts to temps that low flowing over a radiator.

**Dew point** relative to the humidity and the temps internal and external the lines but there is no worry that my temps would ever reach sub 20c near the machine or within the lines themselves. The only location that could maybe achieve 12c (55f) would be the third rad sitting in the air vent but that would have fluid moving through it always well above the dew point.