Cummins QuietConnect RS30 30kW Liquid-Cooled vs Kohler 20RCAL 20kW with ATS
The Cummins QuietConnect RS30 30kW Liquid-Cooled is the more powerful unit: 30,000 running watts against 20,000 — about 33% more capacity for the Cummins QuietConnect RS30 30kW Liquid-Cooled. The Cummins QuietConnect RS30 30kW Liquid-Cooled is the quieter of the two (60 dBA vs 69 dBA — though manufacturers measure noise at different loads and distances). Warranty favors the Kohler 20RCAL 20kW with ATS: 5 years vs 2.
| Cummins QuietConnect RS30 30kW Liquid-Cooled | Kohler 20RCAL 20kW with ATS | |
|---|---|---|
| Type | home-standby | home-standby |
| Fuel | natural-gas, propane | natural-gas, propane |
| Running watts (gas / LP for standby) | 30000 W | 20000 W |
| Running watts (propane) | 30000 W | 20000 W |
| Running watts (natural gas) | 30000 W | 18000 W |
| Noise level | 60 dBA | 69 dBA |
| Output voltage | 120/240V | 120/240V |
| Automatic transfer switch included | No | Yes |
| Main-line circuit breaker | 150 A | — |
| Start type | automatic | automatic |
| Engine | — | Kohler CH1000 |
| Engine displacement | 2400 cc | 999 cc |
| NG use at half load | 219 ft³/h | 161 ft³/h |
| Propane use at half load | 2.7 gal/h | 2.25 gal/h |
| Weight | 1231 lb | 555 lb |
| Warranty | 2 yr | 5 yr |
Frequently asked questions
Which is more powerful, the Cummins QuietConnect RS30 30kW Liquid-Cooled or the Kohler 20RCAL 20kW with ATS?
The Cummins QuietConnect RS30 30kW Liquid-Cooled, at 30,000 running watts on its best fuel versus 20,000 W. Remember that dual-fuel and natural-gas ratings are lower than gasoline ratings — the comparison table shows the published per-fuel figures.
Which costs less to run, the Cummins QuietConnect RS30 30kW Liquid-Cooled or the Kohler 20RCAL 20kW with ATS?
Estimated fuel for 24 hours at about 50% load: $79 on natural gas for the Cummins QuietConnect RS30 30kW Liquid-Cooled vs $58 on natural gas for the Kohler 20RCAL 20kW with ATS, at national average prices. These are spec-sheet-derived estimates — the assumptions are on the methodology page, and different fuels make this a cost comparison, not an efficiency ranking.
Where do these specifications come from?
Every record on BackupAtlas is hand-curated from manufacturer documentation and spec sheets, and each generator page links to its source document.