Question

How long does an LED module last?

Modules are rated for a long life at reduced brightness; in practice the wall is limited by brightness maintenance and by the power supplies before the LEDs fail.

Rated life versus real life

A life rating is quoted at a brightness level, usually half of the original output. It describes slow dimming, not a switch-off date.

What fails first

Power supplies, receiving cards and connectors usually go before the LEDs do. Those are the parts to hold as spares.

Running cooler

Heat is what shortens life. Running a wall below peak brightness and keeping the rear ventilated does more for longevity than any single component.