Preventive maintenance schedules regular inspections and part replacements at fixed intervals, regardless of current equipment condition. Filter changes every three to six months, annual battery load tests, and generator oil changes every 250 to 500 hours fall into this category. Preventive maintenance extends equipment lifespan and catches problems early, making it ideal for mission critical environments where predictable maintenance costs matter more than optimizing every service visit. Get a Reno builds preventive maintenance checklists matched to manufacturer specifications and facility age.