Generac Guardian 18kW (7226)
Generac Guardian 18kW (7226) is a home standby generator from Generac, rated 18,000 running watts on propane and 17,000 W on natural gas, measured at 65 dBA, with 120/240V output.
| Type | home-standby |
|---|---|
| Fuel | natural-gas, propane |
| Running watts (gas / LP for standby) | 18000 W |
|---|---|
| Running watts (propane) | 18000 W |
| Running watts (natural gas) | 17000 W |
| Noise level | 65 dBA |
|---|---|
| NG use at half load | 169 ft³/h |
| Propane use at half load | 1.7 gal/h |
| Output voltage | 120/240V |
|---|---|
| Automatic transfer switch included | No |
| Main-line circuit breaker | 80 A |
| Start type | automatic |
|---|
| Engine | Generac G-Force 800 |
|---|---|
| Engine displacement | 816 cc |
| Weight | 420 lb |
|---|
| Warranty | 5 yr |
|---|
What the numbers mean
- At 18,000 running watts on its best fuel, this unit is sized for whole-house coverage on a typical 200 A home, subject to a load calculation by a licensed electrician.
- Runs on natural gas, propane — expect lower output on propane (roughly 10%) and natural gas (roughly 20%) than on gasoline; the spec table shows the published per-fuel ratings.
- Estimated fuel cost for 24 h at ~50% load: about $61 on natural gas at national average prices (assumptions).
- Permanently installed unit: sizing, gas-line capacity, placement clearances, and the transfer switch are a job for licensed installers under local permits.
Compare the Generac Guardian 18kW (7226)
- Generac Guardian 18kW (7226) vs Briggs & Stratton PowerProtect 12kW (040666)
- Generac Guardian 18kW (7226) vs Briggs & Stratton PowerProtect DX 13kW (040740)
- Generac Guardian 18kW (7226) vs Briggs & Stratton PowerProtect DX 20kW (040657)
- Generac Guardian 18kW (7226) vs Briggs & Stratton PowerProtect DX 26kW (040806)
- Generac Guardian 18kW (7226) vs Champion aXis 14kW with 200A ATS (100837)
- Generac Guardian 18kW (7226) vs Cummins QuietConnect RS13A 13kW
- Generac Guardian 18kW (7226) vs Cummins QuietConnect RS17A 17kW
- Generac Guardian 18kW (7226) vs Cummins QuietConnect RS20A 20kW
Similar generators
- Cummins QuietConnect RS17A 17kW ( 17,000 W running)
- Briggs & Stratton PowerProtect DX 20kW (040657) ( 20,000 W running)
- Cummins QuietConnect RS20A 20kW ( 20,000 W running)
- Cummins QuietConnect RS20AC 20kW with 200A ATS ( 20,000 W running)
- Generac Guardian 20kW (7039) ( 20,000 W running)
- Kohler 20RCA 20kW ( 20,000 W running)
Frequently asked questions
What can the Generac Guardian 18kW (7226) run during an outage?
With 18,000 running watts on its best fuel, the Generac Guardian 18kW (7226) is sized for whole-house coverage on a typical 200 A home, subject to a load calculation by a licensed electrician. Add up your actual loads with a sizing worksheet — the bands here are rough guidance, not a load calculation.
What does the Generac Guardian 18kW (7226) cost to run for a day?
Roughly $61 for 24 hours of continuous operation at about 50% load on natural gas, at national average fuel prices. The assumptions behind this estimate are documented on the methodology page; your fuel price and load change the figure.
Does the Generac Guardian 18kW (7226) start automatically?
Yes — home standby generators monitor utility power and start themselves when it fails; pairing it with an appropriately sized automatic transfer switch (sold separately for some configurations) completes the automatic changeover.
Sources
- www.generac.com (retrieved 2026-07-23)
- www.generac.com (retrieved 2026-07-23)