When to Replace your Generator

When does it make sense to replace an emergency generator system?

As equipment gets older, the potential for parts failures increases. The older the generator the more difficult it may be to source replacement parts. Some manufacturers go out of business. Some manufactures will only continue to produce spare parts for a period of time. When their parts inventory is exhausted it may be impossible to repair the unit. Or, retrofitting the equipment may not be worth the expense.

Reliability, Repairs and Maintenance

Emergency generators are installed for very good reasons, to back up critical electrical needs. If proper maintenance is being performed and failures are popping up regularly the confidence in the equipment to operate when needed erodes. The more critical the need, the more reliable the emergency generator needs to be.

The costs associated with repairs and the risk of unreliable equipment will ultimately outweigh the price of a new generator system.

Older generators should also receive a regular load bank test to insure the integrity of the entire system to carry its name plated load. As equipment ages or facility upgrades are made that could reduce the operating characteristics of the equipment the generator may not be able to handle its intended load.

Increased Capacity Needs-

As buildings age new equipment may be installed. This new equipment may require increased demands on the generator system. Any time loads are added to a building that needs to be backed via the emergency generator; a load study should be completed to insure that the generator can continue to operate as intended. If the load study shows the existing generator can handle the additional load you can be assured that your generator is capable of doing its job when you need it. If not you will either need to shed other loads or consider a larger generator system.

Increased need for operational knowledge-

Modern generators and electrical switchgear have abilities to communicate their status. In critical applications remote monitoring and control may become desirable. Many modern generators also have the ability to tie into building management systems giving facility managers much better data about their equipment.

Going Green

Engine exhaust and noise emissions may become critical for an application. This could result from local code requirement enforcement to providing a better operating environment to the people that are situated close to an operating generator.

Modern engines emit significantly lower exhaust emissions than their predecessors. A desire to reduce exhaust emissions can be derived for many reasons including changing local requirements, EPA regulations limiting run time and a company’s desire to be identified as a “green” company.

Noise is also considered an undesirable effect from operating a generator. Modern enclosure designs can significantly reduce noise levels.

Fuel Considerations

In the case of diesel generators fuel storage can be an issue. Diesel fuel can deteriorate over time and cause performance issues with engines.

Diesel fuel storage can also be influenced by local regulations or the local Fire Marshall. In some cases it may be desired to extend the potential run time of the generator in the event that long power outages may occur. Local requirements may limit the amount of diesel fuel that can be stored on site.  

In recent years natural gas fueled or Bi-Fueled (operates on a combination of diesel and natural gas) generators in larger size ranges have become commercially viable. A desire to move to natural gas can be a motivation.

Long Term Budgets

Replacing a generator can be expensive. As part of a long term capital improvement project the generator system can be replaced as budgets may allow.


In almost all cases a capital investment in a generator system can last for many, many years. As time and requirements take a toll on existing equipment it may make sense to modernize the emergency generator system. In critical applications it is imperative to insure a well-functioning backup solution that can be managed as appropriate by the facilities management team. Sometimes it makes sense to look at replacing old equipment.

How Do You Know It’s Time to Replace Your Generator?

You’ve made the decision to install an electrical generator at your home to protect against power outages and loss of electricity. You’ve maintained and serviced the generator when needed.

But determining whether your generator is working well and will be ready when you need it can be difficult. In the case of a whole house generator, you’re probably not using it 24/7, 365 days a year. In fact, you’re probably using it only sporadically when needed.

That makes determining the health of your current generator tricky, but there are signs you can look for when it is in use that can tell you if it’s time for a replacement.

Start-up problems

Trouble starting up almost any electrical device is a sign that the device is wearing out. Electric generators are no different.

Most generators are designed to turn on automatically when power goes off to your house.  This is operated by the generator’s automatic transfer switch, which automatically transfers the power supply from your outside electrical supply to the generator.

Assuming those switches are working, any delay or lack of power after losing outside power is a sign that your generator either needs repairs or should be replaced. Put simply, it’s not starting and doing its job.

Excessive fuel use

This one can be a vicious circle. You bought the generator to ensure you have electricity. The generator, however, runs on fuel you need to pay for. Ideally, you’d like your generator to at least be as fuel efficient—and therefore as cost efficient—as running on your normal electrical supply.

But older generators can start losing efficiency. If you notice that the generator is using more fuel to provide the same amount of electricity—be conscious of whether you’re using more electricity than in the past—it can be a sign that your generator is wearing out. If it becomes more expensive to run your generator than to use your normal power supply, it’s probably time to upgrade to a more fuel efficient or powerful model.

It needs constant repairs

Like a car, a generator that constantly needs expensive repairs can become too costly to operate. You have to decide if your generator is actually costing you more to fix than a new generator would cost.

You should already have your generator inspected periodically to ensure its working properly. If those inspections keep turning up repairs and worn out components, again, it may be time to buy a new device.

Still, if the repairs are minor, you may decide to stick with the old generator. But as with cars, buying a new generator would give you several years of peace of mind and efficiency with few repairs.

And most importantly, it will decrease the chances of your getting left in the dark.

Do you live in the Minnesota area and have questions about generator installation or replacement? Call us at 612-284-1550.