Kohler vs Generac: How Their Home Standby Generators Compare on Fuel, Output, Installation, and Upkeep

EcoFlow- 2026/10/22

Table of contents

You've sat through one too many long outages, and now two quotes are sitting on the kitchen table. One is for a Kohler standby generator, and the other is for a Generac. Both brands build capable units that start on their own when the grid goes down. So the Kohler vs Generac choice really comes down to model details. Those include output on natural gas versus propane, whether the transfer switch is included, the app, noise data, and upkeep. This guide lines them up using each company's own spec pages, plus a short look at battery backup.

Kohler vs Generac at a Glance: Companies, Lineups, and Comparable Models

If you're comparing Generac vs Kohler, start with who's behind each name. Both sell air-cooled and liquid-cooled home standby generators that kick on automatically when the power fails.

Kohler home generators now come from Rehlko, formerly Kohler Energy. Rehlko says homeowners will keep getting the same Kohler standby units. Generac's home lineup is the Guardian series, which starts at 10 kW.

Comparable models, side by side

Many reviews of Kohler generators vs Generac generators still name older Kohler models like the 14RESA and 20RESD. Kohler's site now lists the 14RCA, 20RCA, 24RCLA, and 26RCA instead. Figures below come from each maker's product page (checked October 19, 2026).

Model	Propane (LP)	Natural gas (NG)	Engine	Transfer switch	Noise listed
Kohler 14RCA	14 kW	12 kW	Kohler CH740 (725 cc V-2)	Sold separately (RCAL version includes one)	63 dB(A) exercise / 67 dB(A) full speed
Kohler 20RCA	20 kW	18 kW	Kohler CH1000 (999 cc V-2)	Sold separately (20RCAL includes one)	64 / 69 dB(A)
Kohler 24RCLA	24 kW	21 kW	Kohler KG2204 2.2L inline-4	Included	54 / 61 dB(A) (spec table)
Kohler 26RCA	26 kW	24 kW	Kohler CH1006 (999 cc V-2)	Page conflicts; confirm with dealer	56 / 67 dB(A)
Generac Guardian 18 kW	18 kW	17 kW	G-Force 800	Varies by package	Not listed on page
Generac 22 kW (cellular)	22 kW	21 kW	G-Force 1000	Varies by package	Not listed on page
Generac Guardian 26 kW	26 kW	22.5 kW	G-Force 1000	Varies by package	Not listed on page

The noise column is lopsided because Generac's pages leave that field blank. Still deciding if a standby unit is right for you? This guide to standby generator types and options shows where it fits.

The two fuel columns matter more than most buyers realize. They decide what you can actually run.

Fuel and Load: Natural Gas vs Propane Output and How to Size Either Brand

Every model above makes less power on natural gas than on propane. The gap runs from 1 kW to 3.5 kW. So size the generator for the fuel you'll actually use, not the bigger headline rating.

Why does this matter? Outages are getting longer. The EIA reliability metrics table shows that the average U.S. customer went 662.6 minutes without power in 2024, including major events. That's about 11 hours, the highest in its 2014 to 2024 series. Without major events, it was 131.6 minutes.

How to size a Generac or Kohler generator

Whether you pick a Generac or Kohler generator, the steps are the same. Work through them before you sign.

List your must-run loads. Think fridge, furnace blower or heat pump, well pump, sump pump, lights, and Wi-Fi. Note each nameplate's running and starting watts.
Choose whole-house or essential circuits. That choice decides your transfer switch.
Match your total to your fuel. Use the NG rating on a gas line and the LP rating on propane.
Get the load calculation in writing. Ask the dealer to show the math so you can compare quotes fairly.

Gas line or propane tank

Natural gas comes from the utility line, so there's nothing to refill. Propane comes from a tank on your property that you keep topped off. Ask your dealer and propane supplier about tank size and runtime for your model.

Not every homeowner who gets a generator quote ends up buying one. Some would rather skip engine upkeep and on-site fuel.

For Homeowners Considering Battery Backup Instead: EcoFlow TITAN Plus

A standby generator runs as long as its fuel lasts. A home battery can't promise that, since its runtime depends on stored energy and how you recharge it. If you're open to battery backup for selected circuits, plan around your loads, their starting needs, hours of storage, and recharging.

Plan the battery system by circuit

For a home battery like EcoFlow TITAN Plus, the plan breaks down into a few parts. Here's how each one works.

Selected circuits: Smart Home Panel 10 (240V) backs up as many as 10 circuits you choose and switches over within 20ms. A licensed electrician installs it.
Starting loads: In EcoFlow's defined 240V scenario, it can start a 3-ton central AC without a soft starter while running about 1kW of essentials. Results depend on your AC and other loads.
Output: It delivers 7,200W from the battery, and up to 10,000W only when compatible solar adds power. More batteries add hours, not watts.
Storage: Each unit holds 5kWh, expandable to 30kWh.
Recharging in an outage: Grid-connected rooftop solar shuts down in an outage for safety. To recharge from the sun, you'd wire panels straight into TITAN Plus's solar inputs (up to 8,000W across two inputs).

A sample runtime estimate

Picture three 5kWh units, or 15,000Wh. Multiply by 0.85 for losses, and you get about 12,750Wh. A fridge using about 1.7 kWh a day plus a 7W router (168Wh a day) needs about 1,868Wh daily. Divide 12,750 by 1,868, and those two loads could run roughly 6.8 days. Central AC, a well pump, or electric heat would cut that sharply.

Which one fits your home?

A fueled standby unit suits homes that need long, heavy-load coverage without watching a battery gauge. A battery suits homes that want selected circuits covered quietly with no fuel on site, and can accept a set runtime between recharges. So judge a battery on the same terms as a generator quote: output, circuits, storage, and recharging.

EcoFlow TITAN 5000 Plus

•100% Whole-Home Backup. 7.2–10kW output and 5kW single-circuit capacity power your 3-ton AC, refrigerator, and the rest of your home simultaneously, with no soft starter required. • 100% Whole-Home Savings. Save up to $4,000 per year, with ROI in as little as 3 years. • Only 30% of Traditional System Cost. Industry-first 200V architecture, custom high-rate LFP cells, and a pre-wired SHP10 help lower costs across the entire lifecycle, from upfront purchase and installation to long-term use. •OASIS 3.0 — Your AI Home Energy Manager. Charges off-peak, powers your home during peak hours, and helps lower your electricity bill every day. •Built to North America’s Highest Safety Standards. UL 9540A tested and UL 9540 certified, with EV-grade LFP cells and 24/7 BMS monitoring.

Buy Now

EcoFlow TITAN Plus fits homes that want selected 120V and 240V circuits backed up with no engine or fuel on site. It isn't a fuel-fed generator and can't promise unlimited runtime. Covering large whole-house loads takes careful sizing, more batteries, and solar.

Winter shows these trade-offs most clearly. This look at home batteries during winter storms covers fuel, noise, and runtime.

Whichever route you take, installation is where the big calls get made. Permits, switches, and placement all get settled here.

Installation, Transfer Switches, Permits, and Placement

Standby generators aren't plug-in appliances. Each needs a pad, a fuel connection, a transfer switch, and permits. Both brands route installation through their dealer networks.

Dealer installation and permits

Kohler's certified dealers offer a free in-home consultation and handle local permits for you. Generac recommends an authorized Generac dealer or a licensed contractor. Its 5-year limited warranty covers units bought and installed through a dealer, applied within 8 weeks after installation and activation.

Installation is often the biggest line in a quote. Before comparing bids, see what drives standby generator installation costs.

Transfer switch options

Transfer switches are where quotes quietly differ. Generac sells automatic switches, like an essential 16-circuit switch and a 200A service-entrance-rated switch, plus manual HomeLink switches. Kohler's RCAL packages include a switch, while RCA models sell it separately. The 26RCA page conflicts on this, so confirm what your Generac vs Kohler generator quote includes.

Placement and safety

Placement is a safety issue. CDC generator safety guidance says to keep a generator outside, at least 20 feet from doors, windows, and vents. For a standby unit, also follow the maker's clearance specs and your local code. The CPSC also released a stationary generator CO report, "Stationary Generators: The Carbon Monoxide Poisoning Hazard and Recommendations for Mitigation," dated June 3, 2025.

California air rules

After installation, ownership comes down to upkeep. That means maintenance, warranty, and knowing your unit is ready.

Maintenance, Warranty, Monitoring Apps, and Noise

Both brands offer five-year limited warranties on the models reviewed. Both run regular self-tests and send app alerts. Maintenance schedules differ by model, so your owner's manual has the final word.

Ownership detail	Kohler (Rehlko)	Generac
Standard warranty	Five-year limited (models reviewed)	5-year limited, dealer install, applied within 8 weeks of activation
Self-test	Weekly exercise listed with dB(A); 26RCA offers a 90-second eco-exercise option	Quiet-Test runs at lower RPM for 5 or 12 minutes
App	Kohler Energy Management App; needs internet; past OnCue users create new logins	Mobile Link; Wi-Fi standard, cellular accessory available; some models require a Mobile Link premium subscription
Service guidance	Check oil after every 8 to 24 hours of operation, depending on model	Service every 6 months by an authorized independent service dealer; check oil every 24 hours of use

What the noise numbers do and don't tell you

Kohler publishes dB(A) figures for weekly exercise and full-speed running, but the Generac pages we reviewed don't. So when you weigh Kohler vs Generac generators on sound, ask each dealer for the spec sheet on your exact model.

Generac also sells PWRcell 2 home battery storage. The Kohler home pages we reviewed don't mention a home battery.

If sound matters near a bedroom or a neighbor's fence, one dB number won't tell the whole story. These tips on choosing the quietest generator cover what else to weigh.

Conclusion

Kohler (by Rehlko) and Generac both make automatic standby generators with five-year limited warranties, so the real Kohler vs Generac differences come down to natural gas versus propane output, transfer switch packaging, published noise data, and apps. Size on the fuel you'll actually use, get a written load calculation, and confirm what each quote includes. If you'd rather back up selected circuits with no engine or fuel on site, EcoFlow TITAN Plus with Smart Home Panel 10 (240V) is worth comparing, sized to your loads.

FAQs

Is Kohler or Generac better?

Neither wins across the board. When you weigh a Kohler generator vs Generac generator, compare specific models: output on your fuel, what the quote includes, warranty terms, and local dealer support.

Do Kohler and Generac generators produce less power on natural gas?

Yes, every model reviewed is rated lower on natural gas. The Kohler 20RCA makes 18 kW on natural gas versus 20 kW on propane, and Generac's 26 kW model drops to 22.5 kW.

What warranty do Kohler and Generac offer?

Both list five-year limited warranties on the models reviewed. Generac's depends on dealer installation and is applied within 8 weeks of activation.

Who makes Kohler generators now?

Rehlko, formerly Kohler Energy, makes Kohler-brand home standby generators. It says the generators themselves haven't changed.

Can a home battery replace a standby generator?

It can cover selected circuits for a set number of hours. But it can't match a fuel-fed generator's nonstop runtime without recharging, usually from solar wired to the battery.