Signs Your Standby Generator Needs Repair

A standby generator is the kind of machine you forget about until the power goes out, and then it is the most important thing you own. The problem is that the moment you need it during a Kansas City ice storm or a summer grid strain is the worst time to discover it has a problem. The good news is that these units almost always warn you first. Here are the signs I tell homeowners to watch for so a small fix does not become a dark house.

Why a standby generator quits when you need it

Most standby failures are not dramatic. A battery slowly dies, a fuel valve gums up, oil goes unchanged, or the controller logs a fault nobody noticed. Because the unit sits idle most of the year, these small issues build quietly and then show up all at once during an outage. That is exactly why the warning signs below matter. Catching one early is a quick service call. Ignoring it is a generator that cranks and quits while your neighbors are also in the dark.

It fails or skips its weekly self-test

Your standby unit runs a short self-test on a set schedule, usually weekly. That hum for a few minutes is the generator proving it can start and run. If you stop hearing it, or you walk out and see a red light or an alarm after a test, treat that as the machine telling you something is wrong. A missed or failed exercise cycle is the single most common early warning I see, and it is the easiest one to act on before the next storm.

It hesitates, surges, or shuts off under load

When the power drops, a healthy generator should start within seconds, take the load, and run steady. Warning signs are a unit that cranks a long time before catching, surges up and down while running, or starts fine and then shuts off once your AC or well pump kicks in. Those point to fuel delivery, a failing battery, or a governor or sensor issue. A generator that cannot hold a steady load is not protecting your home even though it appears to be running.

Warning lights, error codes, and a dead battery

Modern standby units have a controller that flashes codes for a reason. A steady or blinking warning light, a code on the display, or a controller that is completely dark all deserve attention. Battery trouble is the number one culprit behind a no-start, since the battery has to crank the engine before any fuel even burns. If your unit is showing a low-battery or charger fault, or the battery is a few years old, that is a cheap part standing between you and a working generator.

Age, run hours, and what maintenance prevents

Even a healthy generator wears. If yours has a lot of run hours from our frequent KC outages, or it has gone a year or more without an oil and filter change, small problems are compounding whether you see them or not. Rust around the base, a rodent nest in the enclosure, or fuel that smells off are all worth a look. A yearly service catches most of this. You can read what that service covers on our maintenance and repair page, and if the unit is past its useful life it may be time to talk about replacement.

Frequently asked questions