A home generator spends almost all of its life doing nothing. That is the problem. Equipment that sits idle for months and then has to start on demand, in bad weather, at night, is equipment that needs a maintenance schedule more than most.
Here is what actually needs doing, how often, and which parts fail when nobody does it.
Why Generators Fail When You Need Them
Generators rarely fail because the engine wore out. They fail because something small was neglected during the months of inactivity.
The pattern is consistent. A dead battery, stale fuel, a seized valve, a clogged filter, or a transfer switch that has not operated in two years. None of these are dramatic failures. All of them leave you without power during the one event the generator was bought for.
This matters more along the Gulf Coast than almost anywhere else, because the equipment here is bought specifically for storm season and the demand comes in a narrow window when everyone else needs service at the same time. A generator that fails on the second day of an outage joins a very long queue.
The Weekly Self-Test
Standby generators run an automatic exercise cycle, usually once a week for ten to twenty minutes. This is not optional housekeeping. It circulates oil, keeps seals from drying out, charges the battery, and burns off moisture inside the engine.
Two things are worth doing about it. Confirm it is actually running, because owners frequently discover the exercise schedule was disabled or lost after a controller reset. And be present for one occasionally rather than relying on the fact that you have never heard a problem.
When you do watch one, listen for a clean start within a few seconds, a steady engine note without surging, and no visible smoke after the first moments.
Monthly Visual Checks
Five minutes, no tools.
- Clear leaves, grass clippings, and debris from around the enclosure. Airflow matters and vegetation blocks it.
- Look underneath for oil or coolant stains.
- Check the control panel for fault or warning lights.
- Confirm the unit is in AUTO rather than OFF. Technicians leave units in OFF after service more often than anyone would like.
- Look for wasp and rodent nests inside the enclosure. This is a genuine problem here and chewed wiring is a common finding.
Oil and Filters
Oil is the item with the clearest schedule and the biggest consequence for skipping it.
Most residential standby units need an oil and filter change after the first 25 to 50 hours of operation, then annually or every 100 to 200 hours, whichever comes first. The manual for your specific unit governs, and the intervals vary enough between manufacturers that guessing is not safe.
The detail owners miss is that the annual interval applies even if the generator barely ran. Oil degrades with time and with the moisture that condenses inside an engine during months of sitting. An annual change on a unit that logged twelve hours is still an annual change.
After an extended outage, treat the hours as real hours. Four days of continuous running is roughly 96 hours, which puts most units at or past a service interval immediately.
Air Filter and Spark Plugs
The air filter needs inspecting at every service and replacing annually in a dusty or coastal environment. A restricted filter makes the engine run rich, which fouls plugs and wastes fuel.
Spark plugs are typically replaced every other year or at the hour interval the manual specifies. They are inexpensive and they are a common cause of hard starting.
The Battery Is the Most Common Failure
If a standby generator does not start, the battery is the first thing to suspect and usually the answer.
Generator batteries typically last two to three years, and heat shortens that. Louisiana summers are hard on batteries, so the lower end of that range is the realistic expectation here.
What to do about it: check terminals for corrosion and clean them, confirm the charger is working and the unit is not reporting a charger fault, and replace the battery on a schedule rather than waiting for it to fail. Replacing a battery every two years is cheap. Discovering a dead one during a hurricane is not.
A generator that cranks slowly is telling you the battery is going. That symptom is worth acting on the week you notice it.
Fuel
What this involves depends entirely on fuel type.
Natural gas units need the least attention, since supply is continuous and the fuel does not degrade. Check that the supply valve is open and that line pressure is adequate, particularly after any plumbing or utility work.
Propane needs tank level monitoring and a regulator that works. Propane regulators can fail or freeze, and tank level is worth checking at the start of storm season rather than when the forecast turns.
Gasoline, which means most portable units, is the demanding case. Gasoline degrades in as little as 30 days without stabilizer, and ethanol fuel absorbs moisture. Stale fuel gumming a carburetor is the single most common reason a portable generator will not start.
For portables, either run the carburetor dry before storage or use stabilized fuel and run the unit monthly. Doing neither is how a generator becomes a repair bill.
The Transfer Switch
This gets overlooked because it is not the loud part, but it is the component that decides whether the generator can actually power anything.
An automatic transfer switch has contacts that carry full household current and mechanisms that move rarely. Contacts pit, and mechanisms stiffen.
It should be inspected during annual service: contacts checked for pitting and heat damage, connections checked for tightness, and operation verified under load rather than assumed.
A failed transfer switch produces a generator that runs perfectly while the house stays dark, which is a frustrating way to discover the problem.
Coolant and Liquid-Cooled Units
Larger standby generators are liquid cooled and have a cooling system that needs the same attention as a vehicle.
Coolant level gets checked at service, and coolant is replaced on the manufacturer schedule, typically every two years. Hoses are inspected for softness and cracking, and the radiator is checked for debris and corrosion.
Air-cooled units, which covers most residential installations, skip this entirely but depend heavily on clear airflow around the enclosure.
What Salt and Humidity Do
Equipment here ages differently, and the maintenance schedule should reflect it.
Salt air corrodes enclosures, terminals, and the aluminum fins on air-cooled units. Units within a few miles of open water show corrosion noticeably earlier.
Humidity means condensation inside the enclosure and inside the engine during idle months. That is part of why the weekly exercise cycle matters more here than in a dry climate.
Insects and rodents find enclosures attractive year round, since the climate never forces them out. Nests inside a generator enclosure are common and chewed wiring is a frequent cause of no-start conditions.
The practical result is that a generator here benefits from inspection twice a year rather than once, with the second check timed before storm season rather than after.
A Realistic Schedule
- Weekly: confirm the exercise cycle ran and the unit is in AUTO.
- Monthly: five minute visual check, clear debris, look for leaks and nests.
- Before storm season: full inspection, battery check, fuel supply confirmed, load test.
- Annually: oil and filter change, air filter, battery assessment, transfer switch inspection, full load test.
- Every two years: spark plugs, battery replacement, coolant on liquid-cooled units.
- After any extended run: treat accumulated hours as a service trigger.
What a Service Visit Should Cover
Service plans vary enough that it is worth knowing what a thorough annual visit includes, so you can tell whether yours is one.
Oil and filter change, air filter inspection or replacement, and spark plug inspection are the baseline. Beyond that, a proper visit checks battery condition under load rather than just voltage at rest, inspects and cleans the enclosure, verifies the exercise schedule is set and running, checks fuel supply pressure, and inspects the transfer switch contacts.
It should finish with a load test and a report of engine hours, battery condition, and anything found. Hours matter because they drive the next service interval, and nobody tracks them unless the report does.
Ask for that report. A visit with no written record of hours, battery condition, and load test results is hard to distinguish from a visit where somebody looked at the unit and left.
What a Load Test Actually Proves
Running a generator with nothing connected proves the engine starts. It does not prove the unit can carry your house.
A proper load test runs the generator under real electrical load and confirms voltage and frequency stay within tolerance, the transfer switch operates correctly, and the unit holds up for a sustained period rather than a few minutes.
This is the part of maintenance most likely to be skipped and most likely to catch a problem that matters. If your service visit does not include one, ask why.
Final Thoughts
Generator maintenance is unglamorous and almost entirely preventive. Nothing visible improves afterwards, which is exactly why it gets deferred.
The items that actually strand people are small: a battery past its life, fuel that sat too long, a transfer switch that has not moved in years, an exercise cycle that was quietly switched off. All of them are cheap to address on a schedule and expensive to discover during an outage.
One Way AC & Heating installs and services standby generators across South Louisiana, including Houma, Thibodaux, and Chauvin. See our generator installation and electrical services. Estimates are free and the price is agreed before work begins.