Generator trouble can be unusual among home repairs because it tends to hide until the one moment it counts. A heating system with a tired part at least fails while you are using it, so you notice. A generator with a tired part fails when the utility power drops, which is precisely when you cannot spare it. Here are six problems that begin small and grow while the unit sits quietly in the yard, several of them faster on the coast than inland.
A battery losing strength
A standby generator’s battery does two jobs: it turns the engine over, and it keeps the controller powered so the unit remembers when to exercise and what faults it has recorded. As the battery fades, the weekly self-test cranks a little more slowly, which almost nobody notices. Then voltage dips begin resetting the controller, the exercise schedule is lost, the engine sits longer between runs, and starting gets harder still, until the unit cranks once and goes silent on the first night of a hurricane. Batteries last two to four years, and coastal heat and salt push them toward the short end, so replacing one on schedule during yearly service is a small cost against the largest failure here.
Fuel supply that has drifted
For a portable unit the compounding problem is gasoline, which degrades within a month or two and leaves varnish in the carburetor, so the generator that started after the last storm refuses after this one. For a standby unit on natural gas or propane the fuel keeps, but the supply can still fail gradually: a regulator drifts, a supply line that was borderline at installation stays borderline, or a propane tank runs low unnoticed, and each produces a generator that starts and then surges, stumbles, or dies under load. During a service visit these are quick adjustments, and during an outage they make for a dark house.
An oil leak that looks like nothing
A few drops beneath the enclosure seem harmless, and for a while they are. The engine loses a little with each weekly run, and because it runs only minutes at a time, the level falls slowly enough that nobody checks. Then a long outage arrives, the engine runs for two days straight, and the level drops until the low-oil sensor stops it or, if that sensor has quit, the engine runs dry. What began as a gasket is now an engine, and an engine costs most of what a new generator does.
Corrosion salt air brings
This is what sets a coastal generator apart from an inland one. Salt-laden air reaches the battery terminals, the controller connections, the wiring out to the transfer switch, and the switch contacts themselves, and it lays down a film that raises resistance. Resistance means heat and voltage drop, so at first the generator runs but delivers a bit less voltage than it should, which the electronics in the house notice before you do. Later a corroded transfer switch contact may refuse to close, so the generator starts perfectly while the house stays dark, or refuse to open when utility power returns, which is hazardous. The cabinet finish is the other place salt works, and once it is scratched, rust follows. Cleaning and tightening connections and touching up the enclosure are routine items on a coastal service visit; replacing a transfer switch is not.
A sensor that stopped reporting
The oil pressure sensor, the temperature sensor, and the various switches feeding the controller are there to protect the engine and to warn you. When one fails, the controller either sees a fault that is not there and shuts the unit down needlessly, which is annoying but safe, or misses a fault that is there and lets the engine run unprotected. A failed low-oil sensor paired with a slow leak is the recipe for a seized engine. A sensor that has been throwing occasional codes for months is one about to fail outright, and yearly service catches it by reading the fault history and testing each circuit.
Service that keeps getting pushed back
Yearly service catches every item above, which is why deferring it is the problem that compounds all the others. It compounds in one more way that catches people off guard: many manufacturers require documented maintenance before honoring the parts warranty, so a generator three years past its last service may suffer an engine failure that would have been covered and is not. And the interval shrinks after a long run. A unit that carried a house through a multi-day outage has spent most of a year’s oil life and battery cycles in a week and needs attention before it is asked for that again.
What one visit puts right
A generator service visit addresses each of these while it is still minor. The technician load-tests the battery and replaces it on schedule, checks fuel pressure and the regulator, changes the oil and filter and looks for leaks, cleans and tightens every connection and inspects the transfer switch, reads the fault log and tests the sensors, and then runs the generator under a full load, the only test that shows whether it will carry your house. The Generator Care Agreement covers that yearly visit and takes 20 percent off service and diagnostic fees and 15 percent off parts and labor on repairs, which is a sensible arrangement for equipment that only has to work on the worst day of the year.
Better on a quiet afternoon
Russell’s American Mechanical has served Hampton Roads since 1977 and installs and services standby generators across the region. If yours has gone more than a year without service, or ran through last season’s storms and has not been looked at since, schedule a visit online, through the website chat, or by phone. Each of these problems is simpler and less expensive on a calm day in the off-season than during the next storm.