PH530 shutting down (noise) after x-period of time [this fixed it for me]
I've had this problem for a while now (haven't been using the projector in years because of it) and I just keep on coming back to these forums. Anyway, I completely tore it apart and left it like that for about 2 years now. I unscrewed the thermal sensor (link at the bottom of post), took it out and cleaned it a bit. I noticed there was a bit of adhesive going over the connectors and scraped it away, that probably didn't solve anything, just mentioning it. I reconnected the thermal sensor but just left it hanging where it should be mounted and that fixed it for me it appears the projector itself isn't getting too hot, the sensor goes bad before the projector does. I've tested the projector for hours with eco-mode turned off and it just keeps on going =)!
Let me know if it worked for you!
TL;DR : unscrew the thermal sensor and leave it hanging near its original spot.
(can't post links, search for 'Acer PH530 Service Manual' it's on manualslib dot com, page 30.)