Top 5 Reasons Why Your Home Standby Generator Might Fail to Start

And Leave You in the Dark

Power outages are on the rise in many parts of the nation and the result of various factors ranging from an aging power grid, changing weather patterns, lack of tree-trimming by utility providers, or other damage to transmission lines and poles. Disruptions in electrical power can quickly transform your home into a dystopian environment with no heating or cooling and an inability to cook meals or see your way around the house.

Image depicting approaching stormy weather

Standby generators keep your home fully powered during an outage. But, like anything mechanical, they are subject to failure and sometimes occur at the most inopportune times. In the article, we will cover the top 5 reasons standby generators fail to start and how to mitigate against such failures from happening to you.  

Commercial and industrial generator users know the importance of a robust maintenance program with weekly, monthly, quarterly, and annual service routines. Homeowners are encouraged to implement a viable maintenance routine including the use of a qualified service provider for oil and filter changes, and generator testing. Most homeowners sign up for annual service checks while others choose semi-annual generator service.

Qualified service providers are factory-trained and possess a wealth of knowledge through their professional experience. Possible mechanical or electrical issues are quickly spotted by a trained professional and can offer solutions for any emerging issues.

The Top 5 Reason Generators Fail to Start and How to Minimize Risks

1. Battery Failures Lead the Pack

Battery failures lead the pack with roughly half of all standby generator failures to start. Routine battery maintenance is imperative if you want your generator to work as designed. NFPA 110 recommends changing the cranking batteries on a standby generator every 24 months. Most generator service providers also recommend battery replacement every 2 years.

Weigh the cost of battery replacement with the cost of an after-hours service call, including trip charges, labor, and the replacement battery. It’s far less expensive to routinely change the battery every 2 years.

Periodically checking the battery charger operation, internal breaker, power supply and power cord is also recommended. The battery charger is frequently found not working because the breaker tripped the supply to the 120v outlet, or someone simply unplugged the charger because they needed the power and neglected to plug the battery charger back in. These items are routinely checked by trained professional technicians annually or every 200 engine run hours.

2. Lack of Proper Generator Servicing and Maintenance

Generator startup failures can often be blamed on a lack of proper generator service.

Buckeye Power Systems highly recommends hiring an experienced and well-trained service provider for its annual generator service. If you purchase a Cummins generator, we recommend hiring a local Cummins service tech to provide routine annual servicing and warranty repairs, if any. While some homeowners are experienced at changing engine oil and filters, this routine is just one of numerous other tests performed by experienced service providers. Professionals can easily spot developing problems and recommend a solution that eliminates the threat.

Remember, too, oil changes are recommended annually or every 200 engine hours. If you experience a week-long power outage, it’s a good idea to call your Cummins Service Provider. Even if the generator was last serviced only a month ago.

3. The Generator Is Not In “AUTO”

Your automatic standby generator must be in “AUTO” for the generator to work as designed. Service providers often place the generator in “MANUAL” mode while servicing the generator. After the service has been completed, the technician places the generator back in “AUTO”.

Humans do err, so homeowners are advised to check the generator status after a technician has completed servicing the generator. You can do this with a Cummins generator in one of three ways:

  1. Open the access door to the generator to view the display. The illustration below is the display for the Cummins RS20A and other air-cooled models. Check to verify the generator is in “AUTO RUN” and “ON STANDBY” for that next power outage.Cummins air-cooled generator onboard display
  2. Another way to check the generator status is with an in-home remote monitor. Similar in shape to a thermostat, the wall-mounted monitor makes it easy for homeowners to check the generator status without going outside.

Cummins in-home wall-mounted remote display

3. The best way to keep tabs on your Cummins home standby generator is with Cummins Cloud Connect. Your air- or liquid-cooled Cummins generator can also be connected to your home’s WIFI for Internet access. Simply download the free Cummins app on your Smartphone and you will have instantaneous notifications of any changes in generator status. Notifications are sent when the generator starts and runs, stops, or if the generator has developed a “Fault” or problem.

Cummins Cloud Monitoring app for smartphones

So, when a service technician completes servicing the generator, always check to make sure the generator was indeed placed in “AUTO”. The app also enables you to place the generator in AUTO to make things even easier.


4. Generator Engine Cooling System Failures

Worn-out hoses and drive belts are often the culprit of cooling system failures. A generator service provider routinely inspects these for proper working order and belt tension. Radiator cores are also inspected to guard against plugging issues from dust or debris or due to corrosion or dirty coolant.

Experienced generator service technicians can verify the integrity of your generator’s cooling system and recommend remedies when engine cooling issued are spotted.


5. Problems with the Automatic Transfer Switch (ATS)

The Automatic Transfer Switch or ATS also has moving parts requiring inspection and removal of dust and debris. Parts might seize if left in one position for too long. Routine inspections by a trained professional can quickly make emerging issues vanish before developing further.

Older ATS gear may not have replacement parts and require the installation of new gear. Always match the ATS to the generator. While some generic switches can work with most generator brands, you lose many features found on the recommended brand name switch. The Cummins RA200 switch communicates with the control center on a Cummins RS20A generator. Many of the features programmed into the generator control center will result in messages sent to the RA200 switch.


Here’s a Bonus Tip for Diesel Generator Owners

TIP: Fuel Contamination in Diesel Generators

Water and fuel don’t mix. In fact, water is heavier than fuel and drops to the bottom of the fuel tank ready to cause damage to critical diesel engine components. The best way to avoid water contamination is to keep your fuel tank topped off. A topped off fuel tank offers no room for water to condensate or develop. Fuel samples can reveal discoloration, cloudiness, or water at the bottom of a fuel sample.  

Trained generator service technicians know how to check fuel levels between inspections. With regular generator exercises, fuel levels should drop. Power outages will result in a significant drop in fuel levels. If the fuel gauge is not going down and the generator is being exercised regularly, the culprit is the fuel level sensor or mechanical float.

The Bottom-Line …

Routine generator maintenance by a trained and experienced pro is your best preventive step to ensure your home standby generator never leaves you in the dark. Homeowners should routinely monitor the generator status to avoid unpleasant surprises during the next power outage.

Cummins Power Generation manufactures some of the best standby generators in the industry. Your goal as a homeowner should be to keep the generator in “as new” condition with proper monitoring and routine generator service performed by a factory authorized Cummins dealer.