Just replaced the lamp on my projector. It shut down and the ‘lamp replace’ light came on but the lamp looks fine- what would happen if I just left it in there and reset the timer? It’s a Sanyo PLV-Z700
The lamp replacement warning is to do with maintaining 100% image quality, over time the lamp dims and you lose brightness and colour rendition, most bulbs drop below acceptable output after about half their effective life. There’s no technical reason why you shouldn’t keep using the old bulb – just replace it when the picture becomes unwatchable. Lamp timer irrelevant in such a case. Reset it when you put a new one in.