Everyone is familiar with the expression. But how does it apply to your digital projector? Every machine needs maintenance. We either pay a little up front to maintain, or we kick the snowball down the hill and pay a lot later to repair. This is of course true of projectors, and especially true of projectors with 3-LCD optical systems.
All projectors are maintenance-critical due to having several-hundred-watt lamps. These lamps necessitate robust power sub-systems, ballasts to limit lamp current, more complex circuitry to filter the inherent electrical interference, powerful air-cooling systems, and in some cases even liquid-cooling systems. Almost every component inside a projector is a single point of failure. For LCD-type projectors it gets worse. Optical parts such as polarized glass burn over time. The longer maintenance is put off, the more the damage becomes apparent, akin to car tire wear (see here for some great in-depth background on LCDs). If left ignored, by the time the optics get to the point where you or your customer can’t stand to look at the projected image, it’s usually too late. Repairs are much more expensive, and usually well beyond cost-effective.
In many LCD projectors, the optical engine can be broken down to component parts, and we are able to procure replacements for the individual degraded parts. But for some models, the optical engine is sealed together and held in alignment by epoxies or glues. If any one part of the engine degrades, it can only be corrected by replacing the whole optical engine. Worse still, in some cases, the main board must be replaced along with the optical engine, as the mainboard is factory-calibrated to drive the LCDs of the engine. Most OEMs in this bucket will not or cannot provide a means to replace one or the other, so the net impact to the end-user is a repair estimate at 90% the street value of the projector.
Maintenance is key to avoiding this pitfall. Regardless of how well you maintain an LCD projector optical parts will eventually burn, as tires will eventually wear down treads. But drag racing is to tires what no maintenance is to a projector’s optical system. Dust accumulates on the blades of axial fans, in the rotors of blower fans, and in fan ducts leading to restricted airflow. It also accumulates on the optical parts themselves, which functions much like a blanket on the LCD modules and polarized glass. This effectively disables them from being cooled properly. The dustier the environment, the worse this problem typically becomes. Good maintenance practices can greatly reduce these risks. While blowing canned air into the exhaust fans and lens receptacle is better than nothing, the best protection comes from a full and proper maintenance cycle, to clean out dust from where it likes to get trapped deep within a device.
Projectors should be on a cycle for PM at least annually. Projectors in schools, rental/event and some other environments at least every six months. A clean and well maintained projector is a happy, long-living and cost-effective projector.