Folks, we've recently upgraded to Heller MKIII reflow ovens with Gen 9 cooling units. We're running N2 atmosphere at 1000ppm O2 and Kester256 solder paste. We're seeing a big problem with flux residues building up in the cooling section of the process chamber.
Any MKIII users out there with the same issue????
Before the upgrade we ran for a number of years with Heller MKII ovens with Gen 5 cooling units. Main issue with these units was blower motors failing and rails warping. No major issues with flux build up.