Generac vs Kohler

Where they actually differ

Both brands build air-cooled, dual-fuel home standby units, both carry a five-year limited warranty on the models we list, and at 26 kW both run a 999 cc twin-cylinder engine. The headline kW is close enough that it rarely decides anything. The spec sheets show four differences that do.

Output on natural gas

Every rating you see advertised is the propane number. On natural gas most units lose some output, and the two brands lose different amounts at different sizes:

• 14 kW: Generac’s Guardian 14 kW is rated 14 kW on natural gas, no derate at all. Kohler’s 14RCA drops to 12 kW.
• 26 kW: the order flips. Kohler’s 26RCA holds 24 kW on natural gas; Generac’s Guardian 26 kW drops to 22.5 kW.

If your home is on a gas line and you’re sizing close to your loads, compare the natural gas figures, not the headline. Size to your loads first, then check which unit clears it on your fuel.

Engine at the small end

At 14 kW the two use different engines. Generac’s 14 kW runs its 816 cc G-Force 800 twin; Kohler’s 14RCA runs a 725 cc CH740. The smaller Kohler engine burns less propane at full load (about 2.2 gallons an hour against Generac’s 3.07), which matters if you’re on a tank. At 26 kW both run 999 cc and the propane figures are close: Generac 2.06 and 3.63 gallons an hour at half and full load, Kohler about 2.3 and 3.5. The propane guide turns those into tank run times.

How they exercise

A standby unit starts itself on a schedule to stay ready, and the two brands do it differently:

• Generac runs a 5-minute exercise at low speed (Quiet-Test), selectable weekly, bi-weekly, or monthly.
• Kohler runs a 20-minute unloaded exercise on the 14RCA and 20RCA. The 26RCA adds a 90-second EcoExercise option. Intervals are weekly, bi-weekly, or monthly.

The practical difference is time: Generac’s standard exercise runs a quarter as long as Kohler’s 20-minute one, while the 26RCA’s 90-second EcoExercise option is shorter than either. Either way the exercise happens on schedule whether the power goes out or not, so it’s the sound you’ll hear most often.

Sound figures aren’t measured the same way

Both brands publish sound at 23 feet, but Generac measures from the front of the unit and Kohler reports the lowest of eight points around it. On paper the 26 kW units tie at 67 dB running; at exercise Generac lists 57 dB and Kohler 56 dB. Because the methods differ, treat anything within a few decibels as a tie, and ask a dealer to run the unit if noise is a real concern for your site.

What the spec sheets can’t settle

Two things decide most Generac-vs-Kohler purchases and neither is on a spec sheet: who installs and services it near you, and what that dealer quotes for the whole job. The installed price, permits, gas work, and switch usually outweigh any gap between the units themselves. Get quotes for both from dealers who will do the service, and compare the installed cost, not the unit price.

Weights in our catalog aren’t comparable across these two brands either: Kohler publishes shipping weight, Generac publishes unit weight.