A standby generator spends most of its life switched off, and that is exactly why it needs regular care. These are the checks we recommend.
Standby generator sets are a bit of a paradox. They clock up very few running hours, yet they have to start first time on the one day it really matters, when the power goes at a hospital, a hotel or a factory. Most failures are not caused by wear. They are caused by the set standing still for months.
These are the checks we recommend doing regularly.
1. Batteries and charger
Flat or weak batteries are the most common reason a generator fails to start. Check the voltage, make sure the terminals are clean and tight and that the trickle charger is actually working.
2. Coolant and pre-heating
Check the coolant level and the antifreeze mix. If the engine has a block heater, make sure it works. A cold engine is harder to start and slower to take the load.
3. Fuel
Diesel ages in the tank. Water and bacteria can build up and block the filters at the worst possible moment. Drain the water separator regularly, check the tank and change the filters on schedule.
4. Oil and leaks
Check the oil level and look for leaks. Manufacturers give oil change intervals in both hours and months, and on a standby set the months usually run out first.
5. Air intake and exhaust
The air filter, the ducts and the rain cap on the exhaust should be clean and clear. Make sure nothing is blocking the ventilation of the room.
6. Test runs under load
Running for long periods with little or no load can leave unburnt fuel in the exhaust, which is known as wet stacking. So as well as short test starts, the set should be run regularly with a real load, following the manufacturer’s guidance.
The exact intervals depend on the manufacturer, the engine and how it is used, so always follow the manual. Hazel supplies, installs and maintains generator sets with Scania, Perkins and Doosan engines. With an annual maintenance contract built around your installation, these checks become our job instead of yours. Get in touch and we can talk it through.
