April is the month we start getting serious calls. The Atlantic hurricane season officially begins June 1, but Houston doesn’t wait for the calendar. Spring thunderstorms can knock power out for hours. A late-April squall line can take down transmission lines across entire neighborhoods in Katy or Sugar Land before the season even officially starts.
Every year, we respond to emergency calls where the homeowner’s generator fails to start or runs poorly during the first real test. Nine times out of ten, the issue was preventable with basic maintenance. Oil hasn’t been changed in three years. A battery that was weak last fall and never got replaced. A fuel supply problem nobody caught during the weekly auto-test cycle.
This generator maintenance checklist for Houston homeowners is built from what we actually see in the field. Use it as a starting point for your own inspection, and use it to have an informed conversation with whoever services your system.
Start With the Basics: Oil and Filter
Standby generators are essentially small engines. They need clean oil to function. Most manufacturers recommend an oil change every 50 to 200 hours of run time or annually, whichever comes first. In Houston, where a single storm event might run your generator for 48 to 72 straight hours, annual changes at minimum are not aggressive, they’re basic.
Dirty oil loses its viscosity and its ability to protect engine components under heat and load. We’ve opened up generators that haven’t had an oil change in four years. The oil looks like tar. That’s not a unit you want starting up at 2am during a major storm.
Check the air filter while you’re at it. Clogged air filters reduce combustion efficiency and can cause starting problems or rough running. In our climate, dust and humidity can shorten filter service life faster than the manufacturer’s standard interval suggests.
Battery Condition Is the Most Commonly Overlooked Item
Here’s something that surprises a lot of homeowners. Your standby generator has a starting battery, just like a car. And just like a car battery, it degrades over time, particularly through heat cycling in Houston summers.
A weak battery will fail to crank the engine when you need it most. The generator’s automatic transfer switch will detect the outage and send the start signal, and nothing will happen. Most generator batteries should be replaced every two to three years. If yours hasn’t been replaced and you don’t know when it was last done, replace it now before storm season.
We check battery voltage and cold cranking amps on every maintenance visit. Kohler’s service documentation and Generac both publish battery maintenance specs as part of their standard service guides. This is not an item to guess on.
Check the Auto-Test Cycle and Exercise Log
Most standby generators are set to exercise once a week for a short run, usually 10 to 30 minutes. This keeps engine components lubricated, keeps the battery charged, and catches problems before they become emergencies.
But here’s what we see regularly: the exercise cycle is running, the homeowner assumes everything is fine, and nobody is actually paying attention to whether the unit sounds right, whether it’s producing a fault code, or whether the oil level is dropping over time.
Walk outside the next time your generator runs its weekly test. Does it start cleanly? Does it run smoothly without hesitation or rough idle? Is the exhaust clear? These are 60-second observations that can catch a developing problem weeks before it becomes a failure.
If your generator has a remote monitoring system, like Generac’s Mobile Link or Kohler’s OnCue, make sure the alerts are configured and going to an active email address. We’ve seen customers who had fault codes sitting unacknowledged for months.
Fuel System and Transfer Switch Inspection
For natural gas-connected generators, the fuel supply side is relatively low-maintenance compared to diesel or propane systems. But there are still things to check.
Inspect the gas line connections for corrosion or damage, particularly at the flex connector near the generator. Make sure the manual shutoff valve is clearly labeled and operational. Confirm that no landscaping, debris, or wasp nests have blocked the unit’s exhaust or air intake, because both of these happen more than you’d expect in Houston’s climate.
The automatic transfer switch deserves its own check. The ATS is the electrical component that disconnects your home from the utility grid and connects it to the generator automatically. It should be inspected for loose connections, signs of overheating, and proper operation. A compromised ATS can create unsafe conditions and is not a DIY repair item.
Our generator maintenance and tune-up service includes a full transfer switch inspection as part of every visit. This is one area where having a certified technician matters because improper transfer switch work can create backfeed hazards for utility workers.
The Full Pre-Season Checklist
Here’s a condensed version of what we check during a professional spring maintenance visit:
- Oil level and condition: Change if it hasn’t been done in 12 months or 50-plus hours.
- Oil filter: Replace with every oil change.
- Air filter: Inspect, replace if dirty or restricted.
- Spark plugs: Inspect for fouling or wear, replace per manufacturer interval.
- Battery: Load test. Replace if over two to three years old or showing weakness.
- Coolant level and condition: For liquid-cooled units, check level and test freeze point.
- Fuel system: Inspect connections, check for leaks, confirm shutoff valve operation.
- Exhaust system: Check for blockages, corrosion, or loose connections.
- Transfer switch: Inspect connections, test automatic operation.
- Exercise log: Confirm weekly cycle is running and logs are clean.
- Exterior enclosure: Check for pest intrusion, corrosion, physical damage.
- Load test: Run under actual load to confirm output and stability.
The National Fire Protection Association’s NFPA 110 standard sets maintenance benchmarks for emergency power systems. It’s written for commercial applications but the underlying principles apply to residential systems too.
When to Call a Pro Instead of Doing It Yourself
Oil changes and air filter checks are reasonable DIY tasks if you’re comfortable working around engines. Everything else on this list, battery load testing, transfer switch inspection, spark plug replacement, cooling system service, load testing under real electrical load, is better handled by a certified technician.
We say this not to generate service calls, but because we’ve seen the aftermath of DIY repairs that went wrong. A misconnected transfer switch is a serious electrical safety hazard. An overtightened oil drain plug can crack an aluminum oil pan. These are small mistakes with real consequences.
If your generator is past due for service, or if you’ve never had a professional inspection done and you’ve owned the unit for more than a year, now is the time. Pre-season is our busy window, so scheduling early gets you priority access before the rush hits in May and June.
Book your generator maintenance appointment with Critical Power Solutions and we’ll get your system inspection-ready before the first storm has a chance to test it.