Scheduled maintenance is a necessity for all standby generators. The Protector™ maintenance kits contain fuel, air and oil filters, and a funnel and chamois. The maintenance kits for 15, 20, 30, 48 and 50 kW units also include a breather filter. Oil will need to be purchased separately based upon the recommendations listed. Maintenance for the fuel and oil filters is recommended at every 250 hours or 2 years and at 100 hours or 1 year for the air filter. If running in a dusty environment, more frequent maintenance may be required.