Generator maintenance checklist: the standby service visit and the schedule by brand (free Google Docs, Word and PDF)

Published October 1, 2026

• The checklist is free. No signup or email is asked, and the links below go straight to the file.
• Deepsel is our product. It tracks the maintenance agreements these visits are sold under, and the last section says so.
• The checklist is written for trained technicians. It does not replace the owner's and service manuals for the unit in front of you, the nameplate, or local code. Where a printed figure and the manual disagree, the manual wins.

A generator maintenance checklist is the list a technician works through on a standby generator service visit: the controller and site checks, the oil, filter, spark plug and valve work that the engine's hour-and-calendar schedule calls for, a fuel leak test and a fuel pressure reading, a battery and charger test, and a simulated outage that proves the generator starts, carries the house and hands the load back. This one covers the air-cooled home standby units from Generac, Kohler, Cummins, Briggs & Stratton and Champion and prints each manufacturer's figure next to the blank, with an appendix for liquid-cooled units and one for emergency systems under NFPA 110. Without the engine work, the same sheet serves as a generator inspection checklist for the second visit of a two-visit plan. The sheet is also the task list that a generator maintenance contract promises, so the page continues with the generator maintenance schedule for each brand and with the contracts themselves: what they include, how many visits they schedule and what shops charge.

Get it three ways: make your own copy in Google Docs (one click, and the copy goes to your Drive), download the Word version (.docx), or download the PDF. You can also read it in Google Docs first without copying anything. The PDF is seven pages. Sections 1 to 6 of the visit take three pages, and the findings and sign-off take a fourth. An appendix for liquid-cooled units, an appendix for emergency and legally required systems under NFPA 110, and a one-page interval and spec reference by manufacturer follow, each on its own page, so you print only the pages the job needs. Every free checklist in the set is listed on the checklists page, including the boiler maintenance checklist and the water heater maintenance checklist. The contract that sells this visit as an add-on to an electrical plan is the electrical maintenance agreement template.

There is no form and no follow-up email. The checklists that rank for this search today are a one-page upload on Scribd that asks you to "Upload a document to download this document or subscribe to read and download," two software vendors' templates behind a form (Xenia's asks for name, work email, phone number and company name), and a third vendor page that promises a "Printable format" and contains no file.¹²³⁴ None of them prints a target value. The only page in the results for these searches with model-specific numbers is a Colorado contractor's Generac guide, and it lists a 0.040-inch spark plug gap for the 18 kW unit where Generac's current owner's manual prints 0.020.⁵⁶ Kohler's own maintenance schedule page gives one generic "Every 100–200 Hours of Runtime" list for every model.⁷ No page in those results mentions that some engines have hydraulic lifters and need no valve adjustment, separates air-cooled from liquid-cooled tasks, or gives the oil checks a long outage requires.

Contract terms and prices are hard to find as well. Of the ten business pages that rank for "generator maintenance contract," "generator service agreement," "generac maintenance plan" and "generator maintenance cost," three publish a residential plan price (one of them last modified in 2022), and the only sample contract with prices is a scanned image without a text layer.⁸⁹¹⁰

What does a standby generator maintenance visit include?

A standby generator maintenance visit includes a check of the controller's alarms, run hours and exercise timer; a site check for clearances, plant growth, water and rodents; the oil and filter, air filter, spark plugs and, on engines without hydraulic lifters, the valve clearance whenever the manufacturer's hour-or-calendar interval is due; a fuel system leak test and a fuel pressure reading under load; a battery and charger test; an inspection of louvers, wiring and corrosion; and a simulated outage that proves the generator starts, carries the load and transfers back. Each reading goes on the sheet next to the manufacturer's figure.

The engine work is the smaller part of the visit. A generator technician on r/Generator described the owners and companies who treat "changing the oil, oil filter & checking the air filter & spark plugs (maybe changing)" as the whole job, and wrote: "A generator is NOT just an engine!" and "the oil change/engine portion is only about 25% of it."¹¹ Another listed what his visits add: "I keep track of compression readings, keep software updated on all non mobillinked units, run battery analysis with midtronics electronic tester."¹² The sheet takes the same view of the job. It has six sections, in the order of the visit.

1. Before touching anything

The enclosure row asks about nests and chewed wiring. A technician on r/Generator described a 50 kW Generac diesel at a hotel where mice had travelled through the conduit between the generator and the transfer switch: "The mice some how made there way through the conduit from the generator to the ATS and chewed some of the load lines," and the generator end caught fire when the output breaker closed.²⁴

The clearance row comes from a fire standard. NFPA 37 sets the base distance: an engine and its enclosure installed outdoors "shall be located at least 1.5 m (5 ft) from structures having combustible walls," and the 2021 text adds 5 ft "from any openings in the walls of structures."²⁵ A shorter distance to the wall is allowed where the wall has a 1-hour fire rating or "a fire test demonstrates that a fire originating at the engine will not ignite combustible structures,"²⁵ and that fire test is where the 18-inch figures in the manuals come from. A deck built over the unit, a hedge planted against it or a shed added beside it changes the distances the installer measured, so the site row asks for them against the manual at every visit.

2. Engine

Technicians treat the 25-hour valve check as required. A Generac technician on r/Generator wrote: "They NEED to be done after 25 hours because they are installed tight so they can seat properly."²⁸ An owner whose new 22 kW Guardian ran six days straight through an outage checked afterward and reported: "Valve lash was 0.001 which is pretty tight. I've adjusted to 0.003."²⁹

3. Fuel system

Champion's installation manual gives the reason the pressure reading is taken with the house running: a reading that drops below the range while the engine starts or runs "may be an indication that the gas meter or primary regulator is undersized."²⁰ The manometer for that reading is listed with the other test instruments on the HVAC technician tool list.

4. Battery and charger

A voltage reading at rest does not test the battery. A technician on r/Generator wrote: "Just testing voltage of battery is useless. Your testing charger. You need to run load test."³² Battery replacement is also a billing question. An owner on r/Generator whose service company "replaced my 2 year old battery during the service without telling me beforehand and charged me $157 for it" saw the year's bill go from $435 to $620.³³ The findings table on the sheet has an approval box for that reason.

5. Enclosure, alternator and wiring

6. Run test, transfer test and return to service

Dealers expect the transfer switch to be part of the visit even where a contract does not say so. A dealer on r/Generator, asked what a service contract should cover, answered: "I would ask if it involves the ATS. It should be. But may not be written out. One doesn't work without the other."³⁵

Generator maintenance schedule by manufacturer

Every home standby manufacturer runs its schedule on two clocks, run hours and calendar time, and the service is due at whichever comes first. The intervals differ from brand to brand, and the table below gives each manufacturer's figures from its current owner's and service manuals. In the table, "Yearly" means a different job for each brand.

The Generac maintenance schedule: oil every two years, or every year in heat and cold

Generac's own schedule changes the oil every two years in a mild climate. The owner's manual and Generac's help center both put the oil change in Schedule A, "Every Two Years or 200 Hours," and add the yearly change only for cold and hot weather: the manual for ambient temperatures below 40 °F or a unit "operated continuously" above 85 °F,⁶ and the help center for generators in "extremely hot or cold environments below 40°F (<4.4°C) or above 85°F (>29.4°C)."²⁷ Generac's help center also says "Yearly maintenance is performed every 100 hours or every year, whichever comes first," and the yearly tasks in its table are the water intrusion check and the fuel system leak test.²⁷ The cold-weather footnote applies "below 40 °F," so whether a Generac is on the one-year or the two-year oil cycle depends on where it is installed, and the sheet asks which interval the visit is for.

Valve clearance: which engines need it

Generac's 10 kW and 20 to 26 kW Guardian engines need the valve clearance checked after the first 25 hours and then at 400; its 14 and 18 kW units and the Next Generation series have hydraulic lifters, and Generac says they "do NOT require a valve clearance inspection or adjustment."²⁷ Cummins puts the valve adjustment at 25 and 100 hours and then every 200, and reserves it for "a qualified service technician."¹³ Briggs & Stratton checks the lash every 100 hours.²⁶ A plan that promises "valve adjustment" on every unit promises work that some engines do not need.

Spark plug gap: the figure depends on the manual

The figures also change from one manual to the next within a brand. Cummins' 2017 service manual for the RS13A to RS20AC printed a spark plug gap of 0.027 to 0.031 inch; the August 2025 operator manual for the current C13N6H to C20N6HC units prints 0.015 to 0.023.³⁶¹³ The sheet leaves the gap blank next to the manufacturer figures so that the technician reads the manual for the serial number being serviced.

Oil, plugs, valves, battery and exercise: the specs in one table

Two battery specs differ from the usual single 12-volt starting battery. Champion's 22 kW unit starts on 24 volts from two batteries in series,¹⁵²⁰ and Briggs & Stratton calls for 800 cold cranking amps where the temperature drops below 30°F.²⁶ The sheet asks for the group size and rated CCA on the label, and the measured figure next to it.

To plan these intervals across many units, the preventive maintenance schedule template is a 12-month grid with one row per unit, its service interval and the month its cycle starts.

What a generator maintenance contract covers, how often, and what shops charge

A generator maintenance contract (dealers also call it a maintenance agreement, service agreement or maintenance plan) is a yearly agreement in which a dealer or contractor performs the manufacturer's scheduled maintenance on a standby generator, usually in one or two visits a year, for a fixed price, with a repair discount and priority scheduling added. It covers maintenance and leaves repairs out. A Maryland dealer's 2026 contract states this in capitals: "THIS IS NOT A SERVICE CONTRACT This is for maintenance items only, this does not cover generator breakdowns/troubleshooting/repairs/parts/labor."³⁷

Generac maintenance plans are sold by the dealer

The manufacturers leave the contract to the dealer. Generac's help center says: "Does Generac sell maintenance contracts? No. Maintenance contracts or service plans are sold through Generac Authorized Service Dealers," and "The cost of a service plan varies by dealer."³⁸ A Kohler dealer on r/Generator wrote: "Kohler does not offer direct to consumer maintenance."³⁹

What a generator maintenance plan includes: one visit a year or two

The published plans take two forms. In a one-visit plan, the visit is the full annual service: oil and filter, air filter and plugs when due, battery test, fuel leak check and the transfer test, which is sections 1 to 6 of the checklist. A two-visit plan adds a second, shorter visit six months later. One Generac dealer's contract puts the split in writing: "The following items are only performed once a year: 1. Change oil and oil filter 2. Change air filter 3. Change spark plugs 4. Adjust valve lashes," with the inspection done at both visits.⁴⁰ Another dealer's 2026 contract promises a "37 Point Checklist of regular maintenance items replaced and inspected twice a year."³⁷

The manufacturer sets neither form. Generac's schedule asks for the oil change every two years in a mild climate,²⁷ Kohler's and Briggs & Stratton's ask for it every year,¹⁴²⁶ and a Houston technician who services "about 318 generators" reported that "About 25% want yearly service, rest is every other year."⁴¹ Most of the published plans below sell a yearly visit, which on a Generac also meets the cold-weather interval.

Generator maintenance cost: what dealers charge per year

The table lists prices from dealers that publish them, as read on October 1, 2026.

Across the 16 dealers whose current pages publish a one-visit price for an air-cooled unit, the range is $175 to $695 a year and the middle of the list is $275. Across 13 two-visit plans the range is $275 to $625, with the middle at $495.⁵⁰ Liquid-cooled plans cost more at every dealer that prices both: $400 against $275 at Generators of Maine, $595 against $395 at Washington Generators, and $895 against $550 at APEX.¹⁰⁴⁸⁴⁶ Consumer cost guides publish similar ranges. Angi puts a single visit at $171 to $395, with a national average of $273 "based on 1,488 verified projects," and HomeGuide puts annual plans at $200 to $650.⁵¹⁵²

One contractor's breakdown puts most of the price in the drive and the labor. He charges $350 and wrote on r/Generator: "Service kit $30 / Oil between $15-30 / Travel time costs (time and fuel) $105 / Service labor $200."⁵³ Owners who do their own maintenance read the same figures differently: "You are basically paying for the travel. It's not unlike a $39 oil change at a quick lube place (plus a couple of spark plugs) but the tech has to come to you so now it's $300."⁵⁴

Generator service contract terms that cause disputes

The warranty row is the one that the manufacturers back. Generac's five-year limited warranty lists among its conditions "Proof of performance of all required maintenance must be available," and excludes the "Costs of normal maintenance."⁵⁶ Its help center allows owners to do the work themselves: "Generator owners who perform their own maintenance must keep their own detailed records of completed maintenance tasks, in digital form or on paper."⁵⁷ Kohler's operation manual says: "Owners/operators must retain maintenance records."¹⁴ Champion's warranty page says: "Scheduled Maintenance, as outlined by the generator owner's manual is required."⁵⁸ Cummins asks owners to use the engine hours on the status screen to keep "an accurate log of all service performed for warranty support."¹³ A dated, signed checklist with the run hours on it is that record.

Owner and installer reports show what the priority row and the warranty row mean in practice. An agreement holder on r/Generator who called the service company on July 13, 2024, reported the result: "First available appointment Aug 7th."⁵⁹ An installer who advises owners doing their own maintenance to keep receipts and photos warns that "There will typically be a delay in any warranty claims getting processed while you provide records."⁶⁰ Owners and shops who argue for the plan cite service during an outage ahead of the oil change. An r/preppers reply gave the buyer's reasoning: "You don't buy the maintenance contract because the maintenance is hard, especially with a Kohler. You buy the maintenance contract to get priority service."⁶¹ The Houston technician with 318 units under service gave the shop's side: "I have not had an emergency call in probably 5 years during an outage on units i service. I do get them on units i do not service."⁴¹

For the contract document itself, the electrical maintenance agreement template has the generator add-on written as its own section, with the visit scope, the exclusions and its own price line.

During a long outage: the oil checks and the oil change the outage triggers

An air-cooled standby engine's oil interval is counted in run hours, and continuous running reaches it in days. Generac's help center tells owners that "After every 24 hours of continuous run time, Air-cooled Home Standby Generators need to be shut down for a minimum of 30 minutes" for an oil check, a fuel-leak check and a look at the louvers, and that a unit which has run 200 hours since its last service needs the oil and filter changed and the battery inspected.⁶² The owner's manual says: "Verify oil level daily when power outages necessitate running generator for extended periods. Generator will shut down if oil level is low."⁶

Kohler's manual adds a warning that matters on the 14 and 20 kW units: the low oil pressure shutdown "does not protect against damage caused by operating when the oil level is low; it is not a low oil level shutdown."¹⁴ Only the 26 kW model carries a low oil level switch.

A week-long outage puts most of these engines past an oil change before the power comes back, and that oil change is separate from the yearly visit. Some of the plans in the contract section above cap the run hours that a year's price covers.

The field reports match the manuals. An owner whose new Generac 22 kW ran six days through an outage wrote that "by the last two days of the outage, it was burning pretty close to half a dipstick over 24 hours."²⁹ An installer on r/Generator says the bigger problem is that owners do not know the oil check is their job: "people have no idea they could have to add oil during an outage.. they have no idea of what type of oil or what quantity."⁶³ Technicians disagree about the shutdown itself. During the Hurricane Milton outage in Tampa, a technician told a homeowner that "he would skip the 24hr cooldown and just let it run until the power's back on. He'd also skip the oil change (due today)."⁶⁴ The manufacturers' instructions say otherwise, and the sheet follows them.

Liquid-cooled and commercial generators: what changes

A liquid-cooled standby set (Generac's liquid-cooled range runs from 22 to 150 kW³⁸) adds a cooling system, a belt and a heavier engine to the visit, and its schedule is denser. The table below gives the manufacturers' schedules for two common families and a diesel.

Two coolant rules are on the sheet. Generac specifies a 40 to 60 percent mix, names Peak Fleet-Charge 50/50 ethylene glycol, and says "Do not use propylene glycol type coolant"; mixing types or even brands "can produce unsatisfactory results."⁶⁵ Kohler's long-life coolant interval is 5,000 hours or 5 years, with the warning "Do not mix coolant types."²³ Appendix A of the checklist carries these rows, plus the belt, the radiator, the block heater and the freeze point.

Emergency and legally required systems: NFPA 110

A home standby generator is an optional standby system under Article 702 of the National Electrical Code, and neither the NEC nor NFPA 110 sets its maintenance schedule. Article 702 has no testing, maintenance or record section, and NFPA 110, the standard for emergency and standby power systems, lists "Optional standby systems" among the things it "does not cover."²¹⁶⁷ Emergency systems (NEC Article 700) and legally required standby systems (Article 701) are treated differently. Both articles require that systems "be tested periodically on a schedule approved by the authority having jurisdiction," that the equipment "be maintained in accordance with manufacturer instructions and industry standards," and that "A written record shall be kept."²¹ For the testing and maintenance itself, the 2023 NEC points to NFPA 110: "Emergency systems are considered Level 1 systems when applying NFPA 110."²¹

Level 1 applies to systems where a failure "could result in loss of human life or serious injuries"; Level 2 applies to systems where failure "is less critical to human life and safety."⁶⁷ The 2025 edition's Chapter 8 sets these minimums:

Hospitals are held to the same chapter through federal rules. 42 CFR 482.15(e)(2) says "The hospital must implement the emergency power system inspection, testing, and maintenance requirements found in the Health Care Facilities Code, NFPA 110, and Life Safety Code," and the CMS survey item reads "Generator sets are inspected weekly, exercised under load 30 minutes 12 times a year in 20-40 day intervals, and exercised once every 36 months for four continuous hours."⁶⁸ Health care surveys use the 2010 edition of NFPA 110, the one the 2012 Life Safety Code references,⁶⁹ and some section numbers differ in it (the annual load bank test is 8.4.2.3 there).⁷⁰ Appendix B of the checklist carries the Chapter 8 items as rows.

Homes have no equivalent requirement. In the research for this page, we found no state or local rule that requires maintenance or a recurring inspection for a one- or two-family home standby generator. The closest is Texas, where Property Code 202.019 lets a homeowners' association require that a standby generator be "installed and maintained in compliance with ... the manufacturer's specifications" and set "reasonable times, consistent with the manufacturer's recommendations, for the periodic testing."⁷¹ For a home, the schedule is the manufacturer's, and the warranty is what enforces it.

Keeping track of the visits a generator maintenance contract promises

Every contract in the price table promises the same thing: the manufacturer's schedule, kept on time, with the paperwork a warranty claim asks for. The checklist covers the visit. The office also needs a list of who is owed a visit, which visit, and when, and a generator plan complicates that list in ways an HVAC plan does not. The service comes due on run hours as well as the calendar, some customers are on a one-year cycle and some on two, a long outage pulls the next oil change forward, and the battery and valve work run on their own cycles.

If the plans run from a binder or a spreadsheet, start with the free maintenance agreement tracking spreadsheet: one row per agreement, the equipment covered, the visits owed and delivered with dates, and the renewal date. For a generator, write the run hours from this sheet next to each visit. The equipment maintenance log template keeps each unit's readings in one place from year to year. The reasoning behind the ledger columns is in how to track HVAC maintenance agreements, and it applies to generator plans as written.

A spreadsheet works up to about 80 to 100 agreements. Past that point, the job is the one Deepsel does. Deepsel is our product. It keeps the ledger of visits owed versus delivered per covered unit, schedules and invoices the visits on the plan's cadence, sends the booking requests the plan promises and logs them, and warns the office before a paid visit expires unbooked. It works beside Jobber or Housecall Pro and does not replace them. The technician still completes this checklist at the unit, and the office records the visit as delivered in the ledger.

Frequently asked questions

How often should a standby generator be serviced?

A standby generator is serviced at the manufacturer's hour-or-calendar interval, whichever comes first, and in practice once a year. Generac's air-cooled schedule changes the oil every 2 years or 200 hours, or every year or 100 hours in cold weather below 40°F or continuous running above 85°F. Kohler's 20 and 26 kW units change it every year or 150 hours, Briggs & Stratton's every 100 hours or annually, Cummins' every 200 hours or 2 years, and Champion's 22 kW every 2 years or 100 hours. Liquid-cooled units have more on the schedule; Generac's 4.5-liter Protector changes oil every year or 125 hours. Between visits the generator exercises itself weekly or monthly, and during an outage it needs an oil check every 8 to 24 hours of running.

How much does generator maintenance cost per year?

Dealers that publish prices charge $175 to $695 a year for one visit on an air-cooled home standby generator, with $275 in the middle of the list, and $275 to $625 for two visits, with $495 in the middle. Liquid-cooled units cost more: $400 against $275 at one Maine dealer and $595 against $395 at one in Washington. Angi puts a single visit at $171 to $395 with a national average of $273. Batteries, repairs, monitoring subscriptions and the extra oil change after a long outage are usually billed separately.

What does Generac maintenance cost?

Generac does not set the price. Its help center says that maintenance contracts or service plans are sold through Generac Authorized Service Dealers and that the cost of a service plan varies by dealer. Dealers that publish a price for a Generac plan charge $175 per service or $275 for two visits at Smart Energy Solutions in Michigan, $220, $350 or $575 a year at Brite Generators in Kentucky, $275 a year at Midwest Generator Solutions in Indiana, and $495 a year for two visits at TriStar Electric in Maryland.

What does a generator maintenance contract include?

A generator maintenance contract includes the manufacturer's scheduled maintenance (oil and filter, air filter and spark plugs when due, valve adjustment on engines that need it), a battery test, a fuel leak check and a transfer test, in one or two visits a year, plus a repair discount and priority scheduling. Most contracts exclude repairs, battery replacement, monitoring fees and run hours above a cap; one Maryland dealer caps its contract at 100 running hours a year. The renewal, booking and cancellation terms matter as well: auto-renewal with 30 days' written notice to cancel is common, and at least one dealer forfeits a visit that is not booked inside its 60-day window.

Who sells a Generac generator maintenance contract?

Generac's authorized service dealers sell it. Generac's help center says that Generac does not sell maintenance contracts, that maintenance contracts or service plans are sold through Generac Authorized Service Dealers, and that the cost of a service plan varies by dealer. Kohler works the same way; a Kohler dealer on r/Generator wrote that Kohler does not offer direct-to-consumer maintenance. The visits, the exclusions and the renewal terms are the dealer's own, and the price table on this page shows how much they differ from one dealer to the next.

Is a maintenance contract required for a whole house generator?

No manufacturer requires one. Generac lets owners do the maintenance themselves if they keep their own detailed records of completed tasks, in digital form or on paper, because its warranty requires proof that the required maintenance was done. Kohler's manual tells owners to retain maintenance records. A contract buys the visit on time, the transfer test, the record and a place in line after a storm. Dealers rarely guarantee that place; one Houston dealer's terms say priority scheduling is not a response-time guarantee.

Does a Generac 14 kW or 18 kW need a valve adjustment?

No. Generac's 14 and 18 kW Guardian units and its Next Generation series use hydraulic lifters, and Generac says they do not require a valve clearance inspection or adjustment. The 10 kW and 20 to 26 kW Guardian engines do need one: the clearance is 0.002 to 0.004 inch, checked after the first 25 hours and then every 400 hours or 4 years. Briggs & Stratton checks the lash every 100 hours, Cummins at 25 and 100 hours and then every 200, and Champion's 22 kW every 2 years or 100 hours through the dealer.

How often should you check the oil in a generator during a power outage?

The oil is checked every 24 hours of running on Generac, Cummins and Champion air-cooled units, and every 8 hours on Kohler's 14 and 20 kW and on Briggs & Stratton's units. Generac asks for a shutdown of at least 30 minutes every 24 hours of continuous running for the check. A week of running also passes most oil change intervals: 100 hours is about four days and 200 hours about eight. Kohler warns that the low oil pressure shutdown on its 14 and 20 kW units is not a low oil level shutdown, so the level has to be checked by hand.

Sources

1. Scribd, "Monthly Generator Maintenance Checklist" (user upload branded adendorff.co.za) - weekly, monthly and annual grids of check items ("TEST BATTERIES," "CHANGE OIL") with no target values; the download requires "Upload a document to download this document or subscribe to read and download." scribd.com, uploaded March 12, 2025, read October 1, 2026.
2. Xenia, "Generator Maintenance Checklist" template - no intervals or target values; "Download PDF" opens a form asking "First name Last name work email phone number COMPANY NAME." xenia.team, modified September 10, 2024, read October 1, 2026.
3. DataScope, "Basic diesel generator maintenance checklist" - OK / Needs Action items for diesel sets without intervals or values; "Download PDF" opens a modal: "Fill out this short form to receive your PDF template." datascope.io, read October 1, 2026.
4. ToolSense, "Free Electric Generator Maintenance Checklist" - promises a "Printable format for quick access and tracking"; the rendered page contains no download link, form or file. toolsense.io, updated June 9, 2026, read October 1, 2026.
5. Courtesy Electric (Colorado), "Generac Generator Maintenance Schedule Explained" - a Generac oil and spark plug table that lists 2.2 quarts and a 0.040-inch gap for the 18 kW unit and 1.9 quarts and 0.040 inch for 13 to 17 kW; "Routine oil change ... Every 100 hours or once per year"; valves "(usually 0.002 to 0.004 inches)"; no mention of hydraulic lifters. courtesyelectric.com, May 27, 2026, read October 1, 2026.
6. Generac Power Systems, "Owner's Manual, 60 Hz Air-Cooled Generators, 10 kW to 26 kW," Part No. A0001846499 Rev. C, May 12, 2023 - Service Schedule: Schedule A "Every Two Years or 200 Hours" (check battery condition; replace engine oil and oil filter), Schedule B "Every Four Years or 400 Hours" (oil and filter, air filter, spark plugs, valve clearance), yearly water-intrusion check and fuel system leak test; "Remove any shrubs or tall grasses which have grown within 3 ft (0.91 m) of intake and discharge louvers"; water sources "directed away from generator enclosure"; "In cold weather conditions (ambient below 40 °F [4.4 °C]), or if unit is operated continuously in hot weather conditions (ambient above 85 °F [29.4 °C]), change engine oil and filter every year or 100 hours of operation"; "Inspect/adjust valve clearance after first 25 hours of operation"; engine table: spark plug gap 0.020 in (10 and 14/18 kW) and 0.040 in (20–26 kW), hydraulic lifters on 14/18 kW, valve clearance 0.002–0.004 in, oil capacity approx. 1.1, 2.2 and 1.9 qt; battery "12 volts, Group 26R Wet Cell 540CCA ... minimum or Group 35 AGM 650CCA minimum"; "Do not use external battery chargers"; preparing for maintenance, "Press OFF button on controller" and "Remove 7.5A fuse from control panel"; battery work, "Disconnect battery ground terminal before working on battery or battery wires" and "Disconnect white battery charger cable"; oil "API Service Class SJ, SL, or better," Generac 5W-20 gaseous engine oil after break-in; spark plug torque "18.4 ft-lbs (25 Nm)"; exercise "runs for approximately five minutes"; "Verify oil level daily when power outages necessitate running generator for extended periods. Generator will shut down if oil level is low."; leak test "Solution should not be blown away or form bubbles"; fuel pressure "10–12 in water column ... for LP gas, and 3.5–7.0 in water column ... for NG"; utility failure "below 65% of nominal, a five second (dealer programmable) line interrupt delay." generac.com, read October 1, 2026.
7. Kohler Home Energy (Rehlko), "How Often Should You Service a Home Generator?" - "Annual Maintenance (Recommended Minimum)" and "Every 100–200 Hours of Runtime," one list for all models, with no model-specific intervals or values. kohlerhomeenergy.rehlko.com, read October 1, 2026.
8. NNG Automatic Standby Generators (Kilmarnock, Virginia), "Preventive Maintenance Agreement" - "5kW to 26kW (Air-Cooled Engines) $220 per year $340 per year $475 per year 10kW to 30kW (Liquid-Cooled Engines) $260 per year $405 per year $625 per year"; Elite one service a year, Elite Plus two with a 10% parts discount, Premier ("Premiere Service" in the tier list) 3-year term with "Battery replacement performed each term – INCLUDED" and 15%; "renews from term to term with cancellation by either party with 30 day written notice." nngenerator.com, modified August 5, 2022, read October 1, 2026.
9. Weisman Electric Co. (Annapolis, Maryland), Preventive Maintenance Contract (scanned PDF, read by OCR) - "$450.00 - Annual - Routine preventive maintenance performed once per year" and "$600.00 - Biannual"; "This contract is based on a yearly standard run time, not to exceed 100 running hours"; repairs "$195.00 per hour"; "Battery Replacement Authorization: [ ] Check this box to authorize our technician to replace the generator battery," with a $150 labor charge and a $10 disposal fee. weismanelectric.com, 2022 contract posted September 2023, read October 1, 2026.
10. Generators of Maine (Belgrade, Maine), "Generator Service Agreement" - "The annual cost is currently $275 for air cooled generators less than 26 KW" and "$400 for liquid cooled generators 24 kw-80 KW"; "Battery – Test & replace every 4-5 years (Battery not included)"; "the customer is exempt from increased rates on nights, weekends and holidays." generatorsofmaine.com, read October 1, 2026.
11. r/Generator, "$489 for annual maintenance on a Generac 24kw," comment by Any-Tell283 - "they all seem to think changing the oil, oil filter & checking the air filter & spark plugs (maybe changing) is a maintenance"; "A generator is NOT just an engine!"; "Check your owners manual to see what is actually required for a maintenance, the oil change/engine portion is only about 25% of it." reddit.com, June 6, 2026, read October 1, 2026.
12. r/Generator, "Generator maintenance: DIY or hire a pro," comment by grsthegreat - "On all non hydraulic generacs, valves have to be adjusted after first 25 run hours"; "I keep track of compression readings, keep software updated on all non mobillinked units, run battery analysis with midtronics electronic tester." reddit.com, October 5, 2025, read October 1, 2026.
13. Cummins Inc., "Operator Manual, Generator Set for Home Standby, C13N6H, C17N6H, C20N6H, C20N6HC (Spec B-D)," A062J680 Issue 7, August 2025 - Table 13, Maintenance Frequency: check oil every 24 hours ("Check daily during power outages, or monthly without power outages"); change oil and filter at 25 and 100 hours, then every 200 hours or 2 years; adjust valve clearance at 25 and 100 hours, then every 200 hours ("Must be performed by a qualified service technician"); air filter every 200 hours or 2 years; clean and check starting battery every 200 hours; clean slip rings (column "Every 24 Hours or 6 Months"); complete system test every 200 hours or 2 years; "Testing the system once every 200 hours or every 2 years is required to make sure the transfer switch will transfer the load"; spark plug gap "0.38–0.58 mm (0.015–0.023 in)," torque 18–22 ft-lb; oil "Full synthetic gasoline engine oil ... API service SN," 5W30 above 0°F, 0W30 below; capacity 2.3 L (2.4 qt) at the full mark; battery Group 51R, 450 CCA minimum; fuel pressure natural gas 3.5–10 and propane 6–10 in water column, "Maximum pressure for either fuel under any condition: 2.5 kPa (10 inch water column)"; exercise "from 1 to 20 minutes," defaults "Period: Monthly ... Run Time: 5 minutes"; "Use the engine hours shown on the system status screen to keep to keep an accurate log of all service performed for warranty support." cdn.currentconnected.com (dealer copy), read October 1, 2026.
14. Kohler, "Operation, Residential/Commercial Generator Sets, Models 14RCA, 14RCAL, 20RCA, 20RCAL, 26RCA, 26RCAL," TP-7092 9/23 - Service Schedule tables: 14 kW "Change oil ... Yearly or 100 hours," "Replace filter ... Yearly or 200 hours"; 20 and 26 kW "Standard oil change ... Yearly or 150 hours," 26 kW premium oil "2 years or 300 hours"; oil level every 8 hours of operation (14 and 20 kW) and every 24 hours (26 kW); air cleaner check 150, change 300 hours or yearly; spark plugs 300 hours or yearly; battery charger monthly, terminals, electrolyte and specific gravity yearly; flexible fuel lines quarterly, main tank level weekly; wire abrasion 6 months; brushes and collector ring yearly or 300 hours (dealer); winding insulation resistance every 3 years (dealer); "Use 5W-30 or 10W-30 API ... Service Class SG, SH, or SJ synthetic oil"; oil capacity 1.9 qt (14 kW) and 2.0 qt (20/26 kW); spark plug gap "0.76 mm (0.030 in.)," torque 18–22 ft-lb; "Operate the generator set without load once each week for 20 minutes"; the low oil pressure shutdown "does not protect against damage caused by operating when the oil level is low; it is not a low oil level shutdown"; section 4.2.2, "Low Oil Level Switch (26RCA)," and among the shutdown switches "low oil level (26RCA/L only)"; "Owners/operators must retain maintenance records." resources.kohler.com, read October 1, 2026.
15. Champion Power Equipment, "Operator's Manual, Model #100304, 22-kW Home Standby Generator" - Scheduled Maintenance Chart: first 5 hours, change oil and filter; weekly, check the warning LED and clean the louvers; monthly ("or 24 hours of continuous operation"), check oil, fuel lines and battery terminals; "Every 2 Years or 100 Hours of Operation," oil and filter, air cleaner, spark plug, maintenance hour meter reset, and "Complete inspection of generator, engine tune-up, and valve lash check/adjustment" by the service dealer; spark plug gap "0.024-0.035 in. (0.6-0.88 mm)"; "0W-40 Full Synthetic," 2.0 US qt with filter; "Install two (2) 12 volt Group 26 batteries," 540 CCA, starter "Electric 24V DC"; "Exercise duration is system set at 15 minutes"; "Check the oil level daily when the generator is running for an extended period of time." championpowerequipment.com, read October 1, 2026.
16. Generac Help Center, "What Should I Know About Clearance Requirements When Installing My Generator?" - "5 ft. from openings in walls (operable windows, doors, vents, window wells, or other openings in the wall)"; "18 in. of clearance from the back of the generator to a stationary wall or building (based on testing by the Southwest Research Institute, SwRI)"; "5 ft. of clearance above the generator"; "3 ft. of clearance at the front and both ends. This includes trees, shrubs, and bushes"; "Units that do not feature the SwRI logo must be installed 5 ft. from combustible materials and 3 ft. from non-combustible materials." support.generac.com, March 16, 2026, read October 1, 2026. Installation manual for 10–26 kW air-cooled units, A0001846478 Rev. C (December 15, 2022): "DO NOT install under wooden decks or structures"; "Do not attempt to conceal generator with shrubs, bushes, or plants." dealer-hosted copy, read October 1, 2026.
17. Rehlko (Kohler), "Installation, Models 20RCA, 20RCAL, 26RCA, 26RCAL," TP-7091 4/26 - "Furnace and other similar intakes must be at least 3 m (10 ft.) from the exhaust end of the generator set"; no plants, shrubs or "other combustible materials are allowed within 1.2 m (4 ft.) of the exhaust end of the generator set"; wall distances given in drawings. techcomm.rehlko.com, read October 1, 2026.
18. Cummins Inc., "Installation Manual, Generator Set for Home Standby" (RS13A, RS17A, RS20A, RS20AC), A053X172 Issue 16, May 2019 - "All parts of the generator set enclosure must be at least 60 inches (1524 mm) from any openings in walls of structures that may be occupied"; "One side (either engine or alternator) must be located not less than 18 inches (458 mm) from any structures having combustible walls"; the opposite side 60 inches; the intake side 30 inches; the air discharge side 60 inches, with "A minimum of 36 inches (915 mm) must be free of any combustible items." dealer-hosted copy, read October 1, 2026.
19. Briggs & Stratton, 12 kW air-cooled standby generator manual, 80079504 Rev. B - "Standby enclosure must be at least 5 ft (1.5 m) from windows, doors, any wall opening, shrubs or vegetation over 12 inches (30.5 cm) in height"; exhaust outlet 5 ft clear; "a minimum of 5 feet (1.5 m) overhead clearance"; "a minimum of 18 inches (45.7 cm) clearance from any structures with or without a fire rating." retailer-hosted copy, read October 1, 2026.
20. Champion Power Equipment, "Installation Manual, Home Standby Generator, All aXis Controller Models," REV 20250603 - "Manometer stays within 5 -7 inches of water column for NG, 10 -12 inches of water column for LP, with full load applied"; a low reading "may be an indication that the gas meter or primary regulator is undersized"; batteries "MUST be wired in series"; NFPA 37 section 4.1.4 quoted and the clearance "changed to 17.7 inches (45 cm) from the backside of the generator to a combustible wall," 5 ft from windows, 5 ft vertical, 5 ft beyond the exhaust end. championpowerequipment.com, read October 1, 2026.
21. NFPA 70, National Electrical Code, 2023 edition, read on NFPA LiNK free access (page images, transcribed) - 700.1 Informational Note No. 5: "Emergency systems are considered Level 1 systems when applying NFPA 110"; 700.3(B) and 701.3(B): systems "shall be tested periodically on a schedule approved by the authority having jurisdiction"; 700.3(C) and 701.3(C): equipment "shall be maintained in accordance with manufacturer instructions and industry standards"; 700.3(D) and 701.3(D): "A written record shall be kept"; Article 702 (optional standby systems), 702.1 to 702.12, contains no testing, maintenance or record requirement; 702.7(A): for one- and two-family dwellings, "a sign shall be placed at the disconnecting means required in 230.85 that indicates the location of each permanently installed on-site optional standby power source disconnect or means to shut down the prime mover." link.nfpa.org (free account required), read October 1, 2026.
22. NEC 2023 section 445.19(C), Emergency Shutdown in One- and Two-Family Dwelling Units, as reprinted with permission by Leviton's Captain Code 2023 - "an emergency shutdown device shall be located outside the dwelling unit at a readily accessible location"; "The shutdown device shall be marked as the Generator Emergency Shutdown." captaincode2023.leviton.com, read October 1, 2026.
23. Kohler, "Operation, Residential/Light Commercial Generator Sets, Models 38RCL, 48RCL, 48RCLA, 60RCL," TP-6810 8/18 - Service Schedule by hours: oil and filter every 150 hours; air cleaner inspect at 150, replace at 400; radiator exterior and battery charge every 100; belts, coolant replacement and hoses every 1,000; spark plugs 400 and 1,500; fuel system, regulator pressure, exhaust and wiring every 2,000; "Check engine coolant condition and protection, hoses, and clamps annually (prior to cold weather)"; "Long-life coolant is recommended. When long-life coolant is used, the change interval is 5000 hours or 5 years. Do not mix coolant types."; SAE 10W-30 at 0°F and above, 5W-30 below; "Operate the generator set without load every week or every other week for 20 minutes"; prestart check "Check for the installation and operation of carbon monoxide (CO) detectors on each level of any building near the generator set"; "Reset the maintenance timer on the RDC2 controller after changing the oil." resources.kohler.com, read October 1, 2026.
24. r/Generator, "Rats - diesel standby generator problems," comment by LVGGENERATORLLC - on a Generac 50 kW diesel at a hotel: "The mice some how made there way through the conduit from the generator to the ATS and chewed some of the load lines"; the generator end caught fire when the output breaker closed. reddit.com, March 24, 2025, read October 1, 2026.
25. NFPA 37, Standard for the Installation and Use of Stationary Combustion Engines and Gas Turbines, 2024 edition, Tentative Interim Amendment 24-1 (effective May 8, 2024) - "4.1.4.2* Engines and, if provided, their enclosures that are installed outdoors shall be located at least 1.5 m (5 ft) from structures having combustible walls"; a shorter clearance is permitted where structures within 5 ft "have a fire resistance rating of at least 1 hour" or "where a fire test demonstrates that a fire originating at the engine will not ignite combustible structures." nfpa.org; 2021 edition 4.1.4.1, "at least 1.5 m (5 ft) from any openings in the walls of structures," as quoted in the NFPA 37 First Draft public input responses, nfpa.org, both read October 1, 2026.
26. Briggs & Stratton, "Installation and Operation Manual, Single Phase Air-Cooled Standby Generator System, 17 kW, 20 kW, 26 kW," Part No. 80106286 Rev. C - Maintenance Schedule: "Every 8 Hours of Operation or Daily" (clean debris, check oil), "Every 100 Hours of Operation or Annually" (air filter, oil and filter, spark plugs, valve clearance, circuit breaker torques), "Annually" (oil cooler fins); "Perform all service and adjustments at least once each season"; "To receive full value from the warranty, the operator must maintain the generator as instructed in this manual"; spark plug gap .030 in, torque 180 lb-in; intake valve clearance .004–.006 in, exhaust .007–.008 in; oil 5W-30 full synthetic, 78–80 oz with filter; battery 540 CCA standard, 800 CCA "Cold Start (Less than 30° F / -1° C)"; "Natural Gas must be 3.5-7 inches Water Column (WC)," "Liquefied Petroleum must be 11-14 inches WC," at "full load with all gas appliances turned on and in operation." cdn.shopify.com (retailer copy), read October 1, 2026.
27. Generac Help Center, "Where Can I Find the Maintenance Schedule for My Generac Home Standby Generator?" - schedule table for Guardian 10–26 kW and Next Generation 10–28 kW units; "Yearly maintenance is performed every 100 hours or every year, whichever comes first"; "Schedule A maintenance is performed every 200 hours or every two years"; the table's "Every Year" column marks "Inspect for water intrusion" and "Perform fuel system leak test"; "Generators that operate in extremely hot or cold environments below 40°F (<4.4°C) or above 85°F (>29.4°C) require an oil and oil filter change every year or after every 100 hours of run time since last service"; "Next Generation Series generators and the 14 & 18 kW Guardian Series generators use hydraulic lifters, and therefore do NOT require a valve clearance inspection or adjustment." support.generac.com, November 18, 2025, read October 1, 2026.
28. r/Generator, "New Generac 22kW oil burn rate," comment by Sumdood_89 - "They NEED to be done after 25 hours because they are installed tight so they can seat properly. But after that, we adjust valves every 100 hours, and they usually are slightly out." reddit.com, August 21, 2026, read October 1, 2026.
29. r/Generator, "New Generac 22kW oil burn rate," original post and follow-up by Clear-Delivery3630 - a new Guardian 22 kW ran six days through an outage, "by the last two days of the outage, it was burning pretty close to half a dipstick over 24 hours"; afterward: "Valve lash was 0.001 which is pretty tight. I've adjusted to 0.003." reddit.com, August 21 and September 3, 2026, read October 1, 2026.
30. Kohler, "Service, Residential/Commercial Generator Sets, Models 14/20RCA/RCAL," TP-7093 11/20a - engine specifications: "Minimum fuel supply pressure ... NG: 1.2- 2.7 (5- 11) LP: 1.7- 2.7 (7- 11)" kPa (in. H2O); oil pressure 25–35 psi; spark plug gap 0.030 in. resources.kohler.com, read October 1, 2026.
31. McCombs Electrical, Heating and Air (Pace and Milton, Florida), "Generator Maintenance" - annual service $250, biannual $350; "battery load testing. We recommend replacement below 70% capacity and require replacement at 60% or less to prevent starting failures." mccombselectrical.com, read October 1, 2026.
32. r/Generator, "22kW Generac home generator battery options," comment by grsthegreat - "Just testing voltage of battery is useless. Your testing charger. You need to run load test." reddit.com, October 5, 2025, read October 1, 2026.
33. r/Generator, "Am I overpaying for annual generator maintenance?" by PaintingMinute7248 - Kohler owner: "they also replaced my 2 year old battery during the service without telling me beforehand and charged me $157 for it. So my total bill went from $435 last year to $620 this year." reddit.com, August 27, 2026, read October 1, 2026.
34. Generac Power Systems, "Owner's Manual, Automatic Transfer Switch" (100–200 A), Part No. 10000009569 Rev. E, March 20, 2024 - "Shutting off the main disconnect in a subpanel connected to the transfer switch will NOT simulate an outage"; the engine "should crank and start when the utility source power is turned OFF after a five second delay (factory default setting)" and transfer "after a five (5) second warm-up delay"; load-shed module test procedure. generac.com, read October 1, 2026.
35. r/Generator, "Good service contract?" comment by GenMan83 - "I would ask if it involves the ATS. It should be. But may not be written out. One doesn't work without the other so they should be inspecting for issues and proper operation during the visit." reddit.com, January 8, 2024, read October 1, 2026.
36. Cummins Inc., "Service Manual, Generator Set for Home Standby" (RS13A–RS20AC), A053X177 Issue 6, June 2017 - engine specifications: "Spark Plug Gap 0.7 - 0.8 mm (0.027 - 0.031 in)." absolutegenerators.com (dealer copy), read October 1, 2026.
37. TriStar Electric, "2026 Generator Maintenance Contract" (PDF) - "THIS IS NOT A SERVICE CONTRACT This is for maintenance items only, this does not cover generator breakdowns/troubleshooting/repairs/parts/labor"; "37 Point Checklist of regular maintenance items replaced and inspected twice a year"; "We keep all maintenance/service records on file for Generac requests during warranty claim approvals"; "10% up to $200 off non-warranty parts & labor for generators"; "7-28KW Air Cooled 1 YR $495," "22-48KW Liquid Cooled 1 YR $575," "60-150KW Liquid Cooled 1 YR $795"; "SAVE $20.00 - CHOOSE AUTO-RENEW." tristarelectric.net, June 2026, read October 1, 2026.
38. Generac Help Center, "Is There An Extended Warranty Available?" - "Does Generac sell maintenance contracts? No. Maintenance contracts or service plans are sold through Generac Authorized Service Dealers. These optional plans typically cover scheduled maintenance tasks like oil changes, spark plug replacements, valve adjustments, etc. The cost of a service plan varies by dealer." Also: "For liquid-cooled units (22 kW - 150 kW), homeowners have a timeframe of 1 year from the date of activation to secure an extended warranty." support.generac.com, March 16, 2026, read October 1, 2026.
39. r/Generator, same thread, comment by GenMan83 - "Kohler does not offer direct to consumer maintenance." reddit.com, August 27, 2026, read October 1, 2026.
40. Whitehart Energy, "Air Cooled Service Contract" (PDF) - "The following items are only performed once a year: 1. Change oil and oil filter 2. Change air filter 3. Change spark plugs 4. Adjust valve lashes"; 1-year agreement $345 with spring and fall visits. whitehartenergy.com, March 2024, read October 1, 2026.
41. r/Generator, "Houston TX service contract," comment by grsthegreat - "I service about 318 generators. About 25% want yearly service, rest is every other year. Generacs only require service evert 2 years or 200 run hours"; "I have not had an emergency call in probably 5 years during an outage on units i service. I do get them on units i do not service." reddit.com, October 11, 2025, read October 1, 2026.
42. Midwest Generator Solutions (Martinsville, Indiana), "Generac Air-Cooled Maintenance Service Agreement" - "2026 1 year maintenance agreement - $275.00 ... It does not include a battery replacement"; "3 year maintenance agreement - $825.00 (This price includes three (3) basic preventive maintenance services [one per year] including one (1) battery replacement" (prices shown in the enrollment form). midwestgeneratorsolutions.com, read October 1, 2026.
43. Brite Generators (Franklin, Kentucky), "Generac Maintenance Plan" - "Silver Care ... $220 / year," "Gold Care ... $350 / year" with an extra visit, "Platinum Care ... $575 / year"; "All plans include daily remote monitoring"; "Valve adjustment (after 25 hours, then every 400 hours) $250 $99.99 Included." britegenerators.com, updated June 12, 2026, read October 1, 2026.
44. TriStar Electric (Jessup, Maryland), "Generac Generator Maintenance" - "7KW – 28KW Air Cooled Generator 1 Year Plan $495 (2 visits every six months)." tristarelectric.net, June 9, 2026, read October 1, 2026.
45. Premier Energy Solutions (southeastern Massachusetts), "Premier Preventative Maintenance Plan" - "AIR COOLED ANNUAL PACKAGE ($450)," "AIR COOLED PM PLUS PACKAGE – 2 VISITS ($625)," "LIQUID COOLED PACKAGE – 2 VISITS ($650)"; "If you're just looking to meet the minimum requirements to qualify for Kohler's warranty, this is the package you want." gopremierenergy.com, August 1, 2025, read October 1, 2026.
46. APEX Electrical Solutions (League City, Texas), "Maintenance Plan" - "(2) In-Person Visits Per Year," "24/7/365 Remote Monitoring," "Valve Adjustment," "40 Point Inspection and Report"; "1 Year Maintenance Agreement 14-26KW Air Cooled $550," "1 Year Maintenance Agreement 20-100KW Liquid Cooled $895"; "Customer Requested Additional Maintenance outside of Maintenance Schedule $375." aes-hou.com, read October 1, 2026.
47. Critical Power Solutions (Houston), "Maintenance Plans" (GenWatch) - "GenWatch Basic $35/mo $420 per year 1 full service visit a year" for Generac 10–26 kW and Kohler 14–26 kW air-cooled, Premium $50/mo ($600) with two visits; "Priority scheduling is not a response-time guarantee"; "you contact us to book each visit. Unused visits do not roll over." criticalpowerhtx.com, read October 1, 2026.
48. Washington Generators (Kent, Washington), "Maintenance Agreement Terms & Conditions" - "Air-Cooled Generators Base annual maintenance price: $395 per year" and "Liquid-Cooled Generators Base annual maintenance price: $595 per year"; visits "must be scheduled within a 60-day service window"; "Failure to schedule service within this window will result in forfeiture of the annual maintenance visit for that year"; "A $99 cancellation fee applies." washingtongenerators.com, February 5, 2026, read October 1, 2026.
49. Smart Energy Solutions (northern Michigan), "Generac Home Standby Generator Maintenance" - "Basic Maintenance Package: $175.00 per service (excludes battery replacement and additional parts)"; "Advanced Maintenance Package $275 includes two visits annually"; service includes "valve adjustment" and "testing the automatic transfer switch." visitsmartenergy.com, read October 1, 2026.
50. Deepsel price survey, October 1, 2026 - one-visit and two-visit prices for air-cooled units as published on the dealer pages and contracts in this list, plus Doctor Generator (Connecticut, "Annual generator maintenance for $199"), Rack Electric (Florida, "This generator maintenance plan is offered at $195"), Power Plus Systems (South Carolina, $325 annual, "$500 - Semi Annual Maintenance Check ($175) + Annual Full Service ($325)"), Bo's Generators (Florida, "Air-Cooled Home Standby Generator 1 Year $695"), Dynamic Electric (North Carolina, "starting at as little as $279/year"), Preserve Energy Solutions (Houston, "Semi Annual Preventative Maintenance ... $450") and GenCo Generators (Florida, "For just $45 a month"). One-visit list (16 dealers): $175, $195, $199, $220, $220, $250, $250, $275, $275, $279, $325, $395, $420, $450, $450, $695. Two-visit list (13 plans): $275, $340, $345, $350, $350, $450, $495, $500, $540, $550, $600, $600, $625. All read October 1, 2026.
51. Angi, "How Much Does Whole-House Generator Maintenance Cost?" - "In 2026, the national average cost of whole-house generator maintenance is $273, based on 1,488 verified projects from Angi Pros. Most homeowners pay between $171 and $395 per service visit." angi.com, updated September 18, 2026, read October 1, 2026.
52. HomeGuide, "Generator Repair and Maintenance Cost (2026)" - "Annual generator maintenance plans cost $200 to $650 on average." homeguide.com, read October 1, 2026.
53. r/Generator, "$269 to do annual maintenance on my whole house," comment by WhySoManyDownVote - "I change $350 ... Service kit $30 Oil between $15-30 Travel time costs (time and fuel) $105 Service labor $200." reddit.com, April 27, 2026, read October 1, 2026.
54. r/Generator, "Worth it to schedule yearly maintenance for standby?" comment by nunuvyer - "You are basically paying for the travel. It's not unlike a $39 oil change at a quick lube place (plus a couple of spark plugs) but the tech has to come to you so now it's $300." reddit.com, December 12, 2023, read October 1, 2026.
55. Reliable Energy of NJ (Spring Lake, New Jersey), "Generator Preventive Maintenance Service Agreement" (PDF) - "This Agreement will renew automatically for additional terms of one year each unless terminated by written notice at least 30 days prior to the end of the then current Term"; $289 a year with monitoring, $250 without. reliableenergynj.com, June 2024, read October 1, 2026.
56. Generac Power Systems, "5 Year (5M) Limited Warranty for Residential and Commercial Standby Generators" - "Proof of performance of all required maintenance must be available"; not covered: "Costs of normal maintenance (i.e. tune-ups, associated part(s), adjustments, loose/leaking clamps, installation and start-up)." generac.com, read October 1, 2026.
57. Generac Help Center, "What Does My Home Standby Generator Warranty Cover?" - "Proof of performance of scheduled maintenance must be available for warranty claims"; "Generator owners who perform their own maintenance must keep their own detailed records of completed maintenance tasks, in digital form or on paper." support.generac.com, May 5, 2026, read October 1, 2026.
58. Champion Power Equipment Help Center, "Home Standby Generator Warranty" - "Scheduled Maintenance, as outlined by the generator owner's manual is required"; "Unit should be Registered and Proof of Purchase and Maintenance must be available." help.championpowerequipment.com, June 19, 2025, read October 1, 2026.
59. r/Generator, "Whole house generator maintenance," comment by txreddit17 - "my company wasnt even reachable for over a week and a half when needed"; "First available appointment Aug 7th. After calling Sat July 13th. And that is from the company I have a maint agreement with." reddit.com, July 24, 2024, read October 1, 2026.
60. r/Generator, "Generac warranty and maintenance requirements," comment by IllustriousHair1927 - "I recommend anybody that’s going to perform their own maintenance that they keep a small notebook in a drawer"; "Within that notebook, you keep your receipts for the purchase of oil filters"; "take pictures of the unit before and after service"; "There will typically be a delay in any warranty claims getting processed while you provide records but keeping good records like that will be helpful." reddit.com, October 28, 2025, read October 1, 2026.
61. r/preppers, "Do I need a maintenance contract for my whole house generator?" comment by Davegvg - "You don't buy the maintenance contract because the maintenance is hard, especially with a Kohler. You buy the maintenance contract to get priority service." reddit.com, March 19, 2024, read October 1, 2026.
62. Generac Help Center, "Continuous use maintenance for home standby generators" - "After every 24 hours of continuous run time, Air-cooled Home Standby Generators need to be shut down for a minimum of 30 minutes to allow for continuous use maintenance tasks to be performed"; at 200 hours "an oil and oil filter change and a battery inspection"; "it is important to keep records of all maintenance and services performed as indicated in the terms and conditions of the manufacturer's warranty statement." support.generac.com, July 30, 2026, read October 1, 2026.
63. r/Generator, "Cummins 20kW generator annual maintenance cost," comment by IllustriousHair1927 - "people have no idea they could have to add oil during an outage.. they have no idea of what type of oil or what quantity." reddit.com, May 2, 2026, read October 1, 2026.
64. r/Generator, "Skipping 24hr cooldown for Generac," post by mckenney25 - Tampa, day 4 of the Hurricane Milton outage, a technician servicing a neighbor's unit said "he would skip the 24hr cooldown and just let it run until the power's back on. He'd also skip the oil change (due today)." reddit.com, October 13, 2024, read October 1, 2026.
65. Generac Power Systems, "Owner's Manual for Spark-Ignited Stationary Generators," Protector 48, 60 and 80 kW (4.5 L), Part No. A0000253468 Rev. B, July 6, 2020 - Service Maintenance Schedule: 25-hour break-in oil change; daily while running continuously (louvers, fuel hoses, coolant, radiator, oil); Schedule A "Every Year or 125 Hours" (oil and filter, battery, belt tension, air filter; footnote "1 year or 200 hours per oil change"); Schedule B "Every 2 Years or 250 Hours" (drain and flush coolant, spark plugs); Schedule C "Every 1000 Hours" (tighten critical fasteners); coolant 40–60%, "Use only Peak Fleet-Charge® 50/50 ethylene glycol type coolant," "Do not use propylene glycol type coolant," mixing types or brands "can produce unsatisfactory results"; weekly exercise of "approximately 12 minutes." generac.com, read October 1, 2026.
66. Generac Power Systems, "Owner's Manual, Stationary Diesel Generators," Protector 15–50 kW, Part No. 10000019179 Rev. C, June 3, 2020 - Service Maintenance Schedule: 30-hour break-in oil change; daily while running (fuel level, drain fuel filter, fuel lines, coolant, radiator, oil); Schedule A "Every Year or 125 Hours" (battery, v-belt, air filter, breather, governor linkage); Schedule B "Every 2 Years or 250 Hours" (oil and filter, fuel filter element, coolant flush); Schedule C "Every 1000 Hours" (fuel tank, injection valve pressure, valve clearance, injection pump timing, fasteners); weekly exercise of "approximately 12 minutes." generac.com, read October 1, 2026.
67. NFPA 110, Standard for Emergency and Standby Power Systems, 2025 edition, read on NFPA LiNK free access (page images, transcribed) - 1.1.3: "This standard does not cover the following: ... (7) Optional standby systems"; 4.4.1 and 4.4.2 (Level 1 where failure "could result in loss of human life or serious injuries," Level 2 where failure "is less critical to human life and safety"); 8.1.1; 8.3.3; 8.3.4 (transfer switch maintenance); 8.3.6 (batteries, including monthly conductance, ohmic, carbon pile load or cranking voltage drop testing of non-maintainable batteries); 8.3.7 ("A fuel quality test shall be performed at least annually"); 8.4.1 (Level 1 "inspected weekly," Level 2 "visually inspected at least monthly"); 8.4.2 ("at least once monthly, for a minimum of 30 minutes"); 8.4.2.1.1 and 8.4.2.1.2 (diesel loading, spark-ignited "the available EPSS load"); 8.4.2.4 (annual 50 percent for 30 minutes and 75 percent for 1 hour); 8.4.3 ("The EPS test shall be initiated by simulating a power outage using the test switch(es) on an ATS, parallel gear, other remote control system, or by opening a normal breaker"; 8.4.3.2, "the monthly test initiating ATSs shall be rotated to verify the starting function on each ATS"); 8.4.5 (time delays); 8.4.6 ("Transfer switches shall be operated monthly"); 8.4.7 ("EPSS circuit breakers for Level 1 system usage, including main and feed breakers between the EPS and the transfer switch load terminals, shall be exercised annually with the EPS in the 'off' position"); 8.4.9 (Level 1 every 36 months, up to 4 continuous hours); 8.4.10; 8.5.1 to 8.5.4 (records). link.nfpa.org (free account required); scope text also in NFPA's preview of the 2025 edition, nfpanorm.com, read October 1, 2026.
68. 42 CFR 482.15(e)(2), Emergency and standby power systems - "The hospital must implement the emergency power system inspection, testing, and maintenance requirements found in the Health Care Facilities Code, NFPA 110, and Life Safety Code." law.cornell.edu, read October 1, 2026. CMS survey item K918 as reproduced by the Washington State Department of Health - "Generator sets are inspected weekly, exercised under load 30 minutes 12 times a year in 20-40 day intervals, and exercised once every 36 months for four continuous hours." doh.wa.gov, read October 1, 2026.
69. Minnesota Department of Health, "Inspection and Testing of Emergency Generators" (revised June 2024) - "NFPA 101(12), Sec. 2.2 references the 2010 edition of NFPA 110." health.state.mn.us, read October 1, 2026.
70. NFPA 110, 2010 edition, Chapter 8 (scan of the printed pages) - 8.4.2: diesel sets "exercised at least once monthly, for a minimum of 30 minutes"; 8.4.2.3: the annual supplemental load test at 50 percent for 30 minutes and 75 percent for 1 hour; 8.4.2.4: spark-ignited sets exercised monthly "with the available EPSS load for 30 minutes or until the water temperature and the oil pressure have stabilized." whea.com, read October 1, 2026.
71. Texas Property Code section 202.019, Standby Electric Generators - a property owners' association may require "a standby electric generator to be installed and maintained in compliance with: (A) the manufacturer's specifications" and may set "reasonable times, consistent with the manufacturer's recommendations, for the periodic testing of a standby electric generator." Text as reproduced by FindLaw, codes.findlaw.com, current as of January 1, 2026, read October 1, 2026.