What's the purpose of the clearance behind a projector?

[kamion]

Hi all,
First time here. And here's my question: what's the purpose of the clearance required behind a projector when installing it? I just got the Epson TW10 and the manual has indicated a 20cm clearance is required behind it. I thought it might be for cooling purposes but the fan comes out the front and the air filter is from the bottom.

Cheers,
Kamion

[LTJ]

Yes precisely. It's to allow plenty of free flow air. Even though the intake and out take fans are where you say, the PJ needs to avoid any impedance to air flow. These things get bloody hot. and keeping the temperature down helps maintain performance and life span. An example of the heat generated and not just from the lamp itself but the concentrated light as it's channeled and focussed through the system, was brought home to me the other week by a panny engineer who warned me that I should never try and isolate one of the LCD panels when the PJ was on with a slip off paper between the polariser and panel,as this would combust!!