Whole-house generator maintenance costs $273 on average, though it can range from $171 to $395. Keeping the lights on will depend on generator type and any necessary repairs.
The average cost of whole-house generator maintenance cost is $171 to $395, or an average of $273. You can also expect to pay $200 to $600 per year for annual maintenance and upkeep costs. Keep in mind that generator maintenance expenses depend on your generator model, frequency of use, its age, and more. Let’s dig into the costs associated with maintaining a generator.
It isn’t just the type of part that can affect the cost of generator maintenance and repairs. Other factors can cause considerable variation.
| Generator Type | kW | Average Maintenance Cost |
|---|---|---|
| Portable generator | 7–10 kW | $50 |
| Engine generators | 30–45 kW | $600 |
Measurement of the power of a generator is in kilowatts. This can range from 10kW portable varieties to 45kW whole-house standby generators. Powerful large models have more complex engineering, and the cost to repair them will be more.
Different fuel types power generators. Propane and natural gas generators may be more reliable and less likely to require repairs, but the cost to fix them is typically more when they do break down. Gas and diesel-powered generators require more upkeep, and repairs are usually more frequent.
| Type of Fuel | Maintenance Requirements |
|---|---|
| Propane | Repairs are more expensive but less frequent than other generator fuel types. Propane has an indefinite shelf life if stored correctly. |
| Natural Gas | Infrequent repairs needed. Natural gas generators have more expensive installation costs. |
| Gas and Diesel | Requires significant upkeep and maintenance to avoid spills and overfilling. |
Annual maintenance checks will keep your generator running optimally and reduce the requirement for major repairs. An experienced service technician will make sure the generator has the correct levels of lubrication, fuel, and coolant. They’ll also check things like the engine filter, the battery or starting mechanism, and run tests on the transfer switch and voltage output.
Many reputable generator manufacturers offer annual service contracts. Depending on the generator you have and the checks carried out, you can expect annual generator maintenance costs to be around $150 to $300.
Professional generator maintenance is recommended annually. A licensed generator technician will perform several tasks to keep your generator in good condition and inspect for any issues. Common tasks include cleaning the generator, changing the oil and oil filters, inspecting the air intake and electrical systems, and running diagnostic tests.
You can also perform basic maintenance tasks on your own on a daily, weekly, and monthly basis. Each time you power on your generator, check for any signs of leaks, pest activity, or alarming lights.
Often a specific part will cause a problem with your generator, and a technician will need to diagnose what it is and whether it needs repairing or replacing. Below are examples of the average costs to repair or replace some common generator parts.
| Generator Parts | Average Cost |
|---|---|
| Stator and Rotor | $250–$1,500 |
| Carburetor | $60–$500 |
| Engine | $50–$2,000 |
| Voltage Regulator | $80 |
| Transfer Switch | $50–$400 |
The moving rotor sits inside the stationary stator. You can expect to pay between $250 and $1,500 for replacement or rewinding of these pieces of equipment, depending on the size and style of generator you have.
A vital part of your generator’s mechanics, the carburetor mixes fuel and air for the required combustion process. Sometimes it may only need a minor repair, such as fixing a loose gasket, and cost around $50. For a complete carburetor replacement, you could pay anything from about $60 to $500.
You need to keep your generator’s engine ticking over well for smooth operation. Like the carburetor, a small repair may not involve spending much more than $50. Significant repairs or a complete engine replacement could end up costing you upwards of $2,000.
Automatic voltage regulators (AVRs) are vital for ensuring the voltage output remains consistent. This is especially important when you have many major appliances connected to your generator. The part isn’t too expensive, typically not more than $80, and then you’ll also have the technician's labor costs.
All standby generators need a transfer switch to ensure that the mains power does not come into contact with the generator. Repairs are possible and typically cost around $50 to $150. If a switch requires replacement, it’ll usually cost between $200 and $400 for the part and then another few hours of labor costs as this is a detailed job.
In addition to generator maintenance, you can hire your local generator technician for other jobs. If necessary, consider investing in the following services to keep your generator in optimal shape:
Installing a generator transfer switch: $400–$2,500
Installing a circuit: $570–$1,000
Installing a subpanel: $400–$1,750
Wireless monitoring: $200–$400
Backup battery: $10,000–$25,000
Given generator installation costs between $2,000 and $15,000 (or more), maintaining and repairing your investment pays off in the long run. Standby generator repairs (whole-house or partial) are typically jobs for professionals. These devices contain many technical parts and, without the right expertise, diagnosing and fixing the problem will be a real challenge. You risk doing further damage and ending up with an even more costly repair bill when you admit defeat and call in the pro. Plus, because they often run on natural gas, there are safety risks to consider too.
For smaller, more basic portable generators, you may be able to troubleshoot and fix simple problems by topping up the fuel, unclogging filters, or tightening spark plugs. Generator fuel for 24 hours will cost you $30.
Investing in generator maintenance is a necessary expense if you want to maximize the lifespan of your generator. However, there are ways you can cut down on costs:
DIY basic maintenance tasks on a weekly and monthly basis, such as checking for leaks and cleaning the battery.
Shop around for deals on maintenance tools and supplies.
Hire a professional immediately when you notice a problem with your generator. Addressing minor issues can save you money on more serious issues down the line.
Consider buying a smaller model, which costs less to service and maintain.
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If you spot something not right with your generator, even if it’s still working, it’s important to call out a reputable local generator repair technician as soon as possible. Delaying a required repair could mean more costly work later or, worse, it could be a potential safety hazard.
A fuel leak is an example of a major problem that requires immediate attention. A natural gas leak is particularly problematic as this could present an explosion risk.
The cost to install a standby generator is considerable, but they usually come with a warranty. The number of years this is valid for and what it covers will vary. Typically, they last between two and five years, but they don’t normally cover annual services and tune-ups.
