Generator Repair in Nashua, NH

The Most Common Causes, in the Order Techs Check Them

The battery

Start here, because everyone in this trade does. The largest share of no start calls trace to the battery: aged out, weak, corroded at the terminals, or drained by a failed charger. A standby generator asks its battery to crank an engine after weeks of sitting in the cold, which is the hardest job a battery has. Batteries are consumables with a multi year life. If yours is old, untested, or showing corrosion, it is the prime suspect, and its replacement is the cheapest repair in the generator world.

Fuel supply

Engines need fuel, air, and spark, and fuel is the second check. On propane: an empty or nearly empty tank, a closed valve, a regulator problem, or in deep cold a tank too small to vaporize fuel at the rate a loaded generator demands. On natural gas: a valve left closed after other work, a supply issue, or a line problem. A generator that cranks strongly and never catches is often a fuel story. So is one that starts and dies under load in very cold weather on propane.

Missed maintenance made visible

Low oil is a designed shutdown: the unit protects itself by refusing to run, which reads like a failure and is actually the machine saving its engine. Old oil, a clogged air filter, worn spark plugs, and stale service intervals fill this category. The fix is service, and the lesson is the maintenance schedule, which exists to keep this page unnecessary.

Exercise and control faults

A generator that misses exercises or throws fault codes is reporting, not misbehaving. Controllers log faults with codes, and monitoring where fitted reports them onward. Common entries involve the battery and charger, overcrank from repeated failed starts, overspeed or underspeed from fuel or mechanical issues, and transfer switch faults on the electrical side. The code is the beginning of the diagnosis. Write it down exactly as shown before you clear anything or call.

Weather and wildlife

New Hampshire writes its own repair list. Snow drifted against intake or exhaust openings, ice in vents, rodent nests in the enclosure, insect blockages in small orifices, and corrosion from seasons of freeze and thaw all appear regularly. A unit buried in a snowbank cannot breathe, and clearing around it, carefully, with the unit off, is homeowner work.

Transfer and electrical problems

Less common, more serious: the generator runs but the house does not transfer, or transfers and misbehaves. The fault can live in the switch, its controls, or the wiring between equipment. This is licensed electrician territory, full stop.

What You Can Safely Check Yourself

• The controller display: ready, fault, or off, and any code shown, written down exactly.
• The mode: the unit should sit in Auto. A generator left in Off after other work will not start for an outage, and this embarrassment is genuinely common.
• Fuel basics: propane tank gauge level, obvious closed valves if you know your system's normal positions.
• Airflow: snow, leaves, nests, and stored items cleared away from the enclosure, with the unit off while you work around it.
• The obvious: breakers in the generator and transfer equipment that are visibly tripped, noted, not repeatedly reset.

And the boundary, stated plainly: do not open the transfer switch or service equipment, do not bypass safety shutdowns like low oil, do not keep cranking a unit that will not start, and never work around a running generator's moving or hot parts. Carbon monoxide discipline applies to any generator work: these are outdoor machines, never run one in a garage or enclosed space, and treat a unit running in an attached structure's doorway as the emergency it is. The CDC's portable generator guidance, outdoors and at least 20 feet from openings, exists because people die of exactly that mistake every year.

What a Proper Repair Visit Involves

A good service visit starts with the fault history from the controller, not with a parts guess. Battery load testing comes early, fuel delivery is verified under demand, oil and service state are checked, and the unit is run under load after repair to prove the fix under the conditions that exposed the fault. The transfer sequence is tested both ways. Before the tech leaves you should know, in ordinary language, what failed, what was done, what it cost, and what the next likely wear item is. If the generator is under warranty, the paperwork matters: records of past maintenance and proper registration are part of how claims go smoothly, which is why the install and maintenance pages on this site keep returning to documentation.

Repair or Replace: The Honest Conversation

Most standby generators are repaired, not replaced, for most of their lives: batteries, chargers, controllers, regulators, starters, and service items are all replaceable at sensible cost. Replacement enters the conversation when the engine itself is worn or damaged, when parts for an older model become scarce, or when the home has outgrown the unit, a different problem that sizing caused years earlier. A trustworthy repair quote separates those cases: the cost to fix this fault, the condition of the whole machine stated honestly, and the price of replacement as an option, not a threat. Get that same separation in writing if the numbers get large.

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