Hi All, thanks for the walkthrough on opening up the heating elements. Same as David, I put up filters around the air intake since day 1 of owning the unit and the elements are clean without any clogs. (Confirmed once I opened up the unit).

I still get the H2 error whenever I use the heating function, I noticed that if I turn it to around 23-24C with the lowest fan speed, the H2 error may not come on. And often time I cannot increase fan speed probably due to some issues with the circuit board or components. I'm suspecting that the H2 error may be due to electrical/component failures because I have 2 units and both experienced H2 error.... I'm suspecting that they were built to have a life timer or something, and when the time comes, it'd fail no matter what.

Did some digging around on the components and it seems that the 2 components next to each heating elements are thermal switch and thermal fuse, I think that's just for safety purpose and they're not heat or flow sensors.