Why Altitude Matters for Generator Performance
Most generator manufacturers rate their equipment at sea level. At higher elevations — like the 5,000–7,000 feet typical of communities from Twin Peaks to Green Valley Lake — the air is thinner, which means less oxygen is available for combustion. This results in a natural power derating: a generator rated at 22kW at sea level may produce 10–15% less power at 6,500 feet without proper altitude compensation. Generac's Guardian Series generators are engineered to minimize this derating, but proper installation and maintenance are essential to ensure optimal performance at elevation.
Annual Maintenance Checklist for Mountain Generators
Mountain Top Generator recommends the following annual maintenance schedule for all Generac generators installed in the San Bernardino Mountains:
Oil and Filter Change: Generac recommends changing the oil and oil filter every 200 hours of operation or annually, whichever comes first. In mountain communities where generators may run for extended periods during PSPS events or winter storms, more frequent changes may be necessary. Use the oil viscosity specified in your owner's manual for the temperature range in your area — at higher elevations, cold-weather viscosity ratings are important.
Air Filter Inspection: Mountain environments introduce unique air quality challenges — pine pollen, dust from unpaved roads, and smoke from nearby wildfires can all clog air filters faster than in urban environments. Inspect your air filter at every oil change and replace it annually or more frequently if it appears dirty.
Spark Plug Replacement: Replace spark plugs annually or every 200 hours. At altitude, proper spark plug gap and condition are especially important for reliable starting and efficient combustion.
Battery Inspection: The generator's starting battery is critical — if it fails, the generator won't start when you need it most. Test the battery voltage at every service visit and replace it every 3–4 years, or immediately if it shows signs of weakness.
Transfer Switch Testing: Verify that the automatic transfer switch operates correctly by simulating an outage. This should be done annually by a qualified technician.
Mountain Top Generator Service Agreements
Mountain Top Generator offers comprehensive annual service agreements for all Generac generators we install, as well as generators installed by others. Our service agreements include a full annual inspection, oil and filter change, spark plug replacement, battery test, and transfer switch verification — everything needed to keep your generator in peak condition at high altitude. Call us at (909) 414-2803 to learn about our service agreement options.