Hi all- this is my first post and I am not particularly technical so please bear with me!

I have a fairly new (500 lamp hours but out of warranty) Optoma uhd30 that recently developed an annoying whining noise that starts up after about 15 minutes of use. The noise is not affected when I play a 3D signal or the test signal. I have cleaned the fans (which both fire up when I turn the projector on) and also tried stopping the fans physically and the noise was still there. I therefore concluded that the noise must be coming from the colour wheel.

I cleaned the colour wheel but the noise remained. I therefore decided to replace the colour wheel, which I have just done using a new Chinese import wheel.

Having replaced the colour wheel I now have another problem. Now when I turn the projector on the lamp, fans and colour wheel start up initially (and I briefly see the Optoma image on my screen) but after about 30 seconds the lamp turns off and the main blower fan goes into idle mode- with a blue power light only showing on the control panel. I tried putting the old colour wheel back in, but get the same result.

I am at a bit of a loss. Obviously I won't know if the new colour wheel solved the noise issue until I can get the lamp to stay on! It seems to me that the new problem is probably not colour wheel or fan related and surely the lamp can't need replacing after only 500 hours (and it is turning on, albeit briefly, and I am not getting a lamp error light)? My only thought is whether this could be a problem with the thermal sensor (although presumably I would get a temp warning light?) or some connector to the main board having come loose?


Any ideas gratefully received!!

Many thanks for your reply. Since my post Frank has actually kindly replied on YouTube and asked if I had replaced the original lamp housing (which apparently could cause this problem) - I haven't - and suggested I check if the wires joining the index sensor to the PCB are broken; they are not although I noticed a tiny cut in the insulation on one of the wires, but covering it with insulating tape made no difference.

As for the original noise problem, it only started after about 6months of use and is v noticeable during quieter moments in films etc, so I would say it is not "normal" or acceptable unfortunately (it is also loud by comparison to footage of similar projectors I have seen online).

Annoyingly I have no idea what else to try so I think it's a return to Optoma!