Canterbury, NH Standby Generator Installation & Maintenance — Why It Won't Start

Estimated Read Time: 9 minutes

When a storm hits and your standby generator won’t start, minutes feel like hours. This guide breaks down the top 7 causes and the safe fixes homeowners can try before calling in help. If you prefer a pro, our licensed electricians handle installation, repair, and maintenance across Southern NH, with 24/7 emergency response and strong warranty protection.

1) Dead or weak battery

A weak or dead battery is the number one reason a standby generator will not crank. Batteries lose capacity from age, cold snaps, and long periods without exercise. Your unit’s charger can also fail, leaving the battery undercharged. As your system ages, cables corrode and loosen, causing voltage drop. If your generator does not start at all, there is a good chance the battery is the issue.

What you can try

1. Check the display for a low-battery or charger fault alert.
2. Inspect battery terminals for corrosion. Clean with a baking-soda solution and a soft brush. Tighten carefully.
3. Verify the battery disconnect switch is on. Some enclosures have a service switch owners forget after maintenance.
4. If you own a multimeter, confirm 12.6 volts or higher at rest for a 12-volt battery. Anything below 12.2 is low.

When to call a pro

• Repeated low voltage, swollen case, or 3 to 5 years of age signals replacement.
• Charger, controller, or alternator output testing requires proper tools and safety training.

Pro tip for New Hampshire winters

• Cold weather is hard on batteries. Ask about a cold-weather kit and annual battery load test during maintenance.

2) Fuel supply problems

Standby generators need the right fuel, at the right pressure, with clean delivery. Natural gas units depend on proper line sizing and a stable supply. Propane units need adequate tank level and a regulator working within spec. Clogs, leaks, or air in lines cause hard starts and shutdowns.

What you can try

1. Natural gas: Confirm other gas appliances work. If they are struggling, the supply may be restricted. Call your utility and a licensed electrician or plumber.
2. Propane: Check the tank gauge. Many regulators need at least 30 percent to maintain stable pressure under load.
3. Look and listen for leaks. If you smell gas, evacuate and call your utility and emergency services.
4. Make sure the fuel shutoff valve at the unit is open.

When to call a pro

• Line sizing, regulator issues, and leak checks require licensed service. We test inlet pressure under load and verify proper orifice and regulator performance.

Local insight

• Seacoast salt air and winter ice can affect regulators and fittings. Preventative checks before storm season protect reliability.

3) Clogged air filter or restricted airflow

Engines need the right air-fuel mixture. A clogged air filter, nests in the intake, or snow stacked around the enclosure will choke the engine. Over time, dust and pollen collect on the filter media and reduce airflow. The engine may start and stall or surge under load.

What you can try

1. Inspect the air filter. Replace if it looks dark, oily, or crumbling. Keep a spare on hand.
2. Clear snow, leaves, and grass clippings from all sides of the enclosure. Maintain the manufacturer’s clearance.
3. Check for rodent nests in the intake area if the unit has been idle.

When to call a pro

• If the engine hunts or surges after a filter change, mixture or governor adjustments may be needed. That is a service visit.

Seasonal tip

• After fall cleanups in Manchester, Derry, and Londonderry, confirm debris has not drifted into the intake or louvers.

4) Low oil, coolant issues, or safety sensor faults

Modern generators protect themselves with sensors. Low oil, high temperature, and low coolant shutdowns are common when maintenance is overdue. Small leaks, failed caps, or a dirty radiator can trigger faults. In winter, thick oil increases cranking resistance and can trip safety switches.

What you can try

1. Check oil level on a level surface. Top off with the exact grade your manual calls for. Never overfill.
2. Look for coolant leaks or dried residue around hoses and clamps.
3. Gently blow dust from the radiator fins with low-pressure air.
4. If a fault persists, power the controller off and on to clear a nuisance code once. Do not repeatedly reset.

When to call a pro

• Sensor failures, oil pressure testing, and coolant service require tools and training. We verify sensor values, change oil and filters, and perform a heat-run test to confirm stability.

Hard fact

• Many whole-home generator repairs are needed due to a lack of effective maintenance. Catching fluid and cooling issues early prevents costly damage.

5) Starter, alternator, or control board faults

If the unit clicks but will not crank, the starter motor or solenoid may be failing. If it cranks but never fires, you may have ignition or control issues. Control boards can fail from power surges, moisture, or age. Alternator problems will show up as low voltage or frequency out of range once running.

What you can try

1. Listen to the sound. Single click without crank often points to the starter circuit. Rapid clicking can be low battery.
2. Inspect visible harness plugs for looseness or corrosion. Do not disassemble sealed connectors.
3. If the generator starts but electronics flicker, switch to utility power and shut the unit down. Avoid running valuable appliances on unstable output.

When to call a pro

• Electrical diagnostics on high-voltage systems is not a DIY task. We test relays, windings, and control boards and replace failed parts with manufacturer-approved components.

Warranty note

• We stand behind our installs with a 2-year parts and labor warranty. Club members receive 3 years for added peace of mind.

6) Transfer switch or wiring problems

Even if the engine runs, a faulty transfer switch can prevent your home from receiving power. Loose lugs, burned contacts, or miswired sensing circuits cause failure to transfer or nuisance trips. Incorrect bonding and grounding can also produce error codes and unsafe conditions.

Safety first

• Never open a live transfer switch. It contains utility-side voltage. Only a licensed electrician should service it.

What you can check safely

1. Confirm the generator is not in “manual” or “off” mode on the controller.
2. Verify the utility power status on the display. Some systems will not transfer during brownouts.
3. Note any error codes before you reset. Share these with your technician.

What we do on a service call

• Inspect conductors and terminations, test coil operation, clean or replace contacts, verify neutral-ground configuration, and simulate an outage to confirm safe transfer per the National Electrical Code.

Local compliance insight

• Municipalities around Nashua and Concord expect permitted, code-compliant transfer switch installs. Professional installation avoids inspection failures and insurance issues.

7) Skipped maintenance and missed exercise runs

Standby generators are designed to self-test weekly. If exercise runs are disabled, small issues grow into big ones. Old oil loses protective properties. Spark plugs foul. Belts and hoses age and crack. Firmware updates and controller checks never happen without a service plan.

What you can do

1. Confirm the weekly exercise is scheduled and has a convenient time.
2. Keep a simple log of alerts, run hours, and any unusual sounds.
3. Replace air filters and spark plugs at manufacturer intervals if your manual permits owner service.

Why a plan pays off

• Regular maintenance is key to keeping your generator in top condition. We offer comprehensive maintenance services to ensure that your generator is always ready to go when you need it. Our Paul’s Promise Plan adds extended warranty, priority scheduling, and exclusive savings so you are never left in the dark.

How professional maintenance prevents no-start calls

• Battery load tests catch weak batteries before winter.
• Fuel pressure and regulator checks prevent hard starts.
• Oil, filter, and cooling service protect engines under heavy storm loads.
• Full-system test under load verifies stable voltage and frequency.

DIY vs pro: a quick decision guide

Handle these yourself if you are comfortable

1. Visual checks for snow, debris, and airflow clearance.
2. Checking oil level and topping off with the correct grade.
3. Replacing an air filter and logging weekly exercise runs.

Call a licensed electrician promptly for

1. Battery replacements, charger faults, and wiring issues.
2. Fuel supply problems, regulator concerns, or any gas smell.
3. Transfer switch faults, repeated error codes, or voltage instability.

Why choose a pro team

• Our team of experts is here to help with all your generator needs. We offer: Generator Installation, Generator Repair, Generator Maintenance. With fast response times and 24/7 emergency service available, we get you back online safely.

Planning an upgrade or new install

If your generator is over a decade old, undersized, or unreliable, upgrading can be smarter than chasing repairs. We help you right-size the system for your home’s appliances, heat source, and future plans. Proper line sizing, code-compliant transfer switches, and cold-weather kits are standard parts of our installs.

What you get with a professional installation

1. Sizing and product selection based on real load calculations.
2. Safe electrical connection and permitting for local compliance.
3. Clean placement, noise considerations, and homeowner training.
4. Backed by a 2-year parts and labor warranty, or 3 years for club members.

Local insight for Southern NH homes

• Oil or gas heat, well pumps, and sump pumps are common here. We plan for these critical loads so your home stays safe during snow and ice events.

Emergency response and rapid repairs

When your generator fails during a storm, speed matters. Our trucks carry common batteries, filters, sensors, and controllers to handle the most frequent failures on the first visit. We diagnose the root cause, not just the symptom, so you avoid repeat outages.

What our licensed electricians check

1. Mechanical components like belts and cooling systems.
2. Fuel systems for leaks, pressure, and regulator function.
3. Electrical components, starting systems, and control boards.

Fast action and clear pricing

• Upfront pricing before work begins, options explained in plain language, and warranties that back the repair. That is how we do business across Nashua, Manchester, Portsmouth, Dover, Concord, Derry, Salem, Merrimack, Londonderry, and Hudson.

Special Savings on Generator Installation

• $250 OFF Generac generator install. Expires 2026-02-04. Present coupon prior to starting job and mention at time of booking. Valid on standard pricing only. Limit one per household. Cannot be combined with other offers.
• Save $100 on generator installation. Expires 2026-02-04. Present coupon prior to starting job and mention at time of booking. Valid on standard pricing only. Limit one per household. Cannot be combined with other offers.

Ready to size and install your standby generator the right way? Call (603) 541-7986 or book at https://www.paultheplumbernh.com/. Mention your chosen offer before scheduling to lock in savings.

What Homeowners Are Saying

Frequently Asked Questions

How do I reset my standby generator after a fault?

Power the controller off, wait 30 seconds, then power it back on and clear the code once. If the fault returns, stop and call a licensed technician to avoid damage.

How often should my generator exercise?

Most brands recommend a weekly exercise run. Pick a time that will not disturb neighbors. Ensure the run completes and does not log new alerts.

How long do standby generator batteries last?

Typically 3 to 5 years in our climate. Cold winters shorten lifespan. Have your battery load-tested annually to catch weak cells before storm season.

What maintenance does a standby generator need?

At least annual service that includes oil and filter changes, air filter and spark plugs as needed, battery and charger tests, fuel pressure checks, and a full load test.

Do I need permits for a new generator and transfer switch?

Yes. Electrical and fuel work usually require permits and inspections. Professional installation ensures compliance with local codes and utility requirements.

Wrap-Up

If your standby generator will not start, begin with the simple checks in this guide, then call a licensed pro for anything involving fuel, wiring, or persistent faults. For reliable power in Southern NH, Paul The Plumber is your trusted partner for installation, repair, and maintenance with strong warranties and 24/7 response.

Get Help Now

• Call: (603) 541-7986
• Schedule: https://www.paultheplumbernh.com/
• Active offers: $250 OFF Generac install or $100 OFF generator installation. Expires 2026-02-04. Mention your coupon when booking for savings.

Need service today in Nashua, Manchester, the Seacoast, or Greater Concord? Call now and we will dispatch a licensed, background-checked electrician to get your generator ready for the next outage.

About Paul The Plumber

Family-owned and serving Southern New Hampshire for over 22 years, Paul The Plumber delivers expert electrical and generator services with upfront pricing and no surprises. Our licensed, background-checked technicians are BBB accredited with an A+ rating and stand behind every install with a 2-year parts and labor warranty, or 3 years for Paul’s Promise Plan members. From Nashua to the Seacoast and Greater Concord, we’re known for reliable work, respectful service, and fast emergency response.