Last updated: March 2026

Guardian 28kW

Power: 28kW LP / 25kW NG
Installed Cost: $16,000–$25,000
Noise: 67 dB
Weight: 524 lbs
Warranty: 5 years
Fuel: Dual-fuel (NG/LP)

Best for: 4,000+ sq ft homes. Largest residential air-cooled from any brand.

The 28kW is the top of Generac's residential air-cooled lineup and the largest air-cooled standby generator from any major brand. It's also the only Guardian that ships with WiFi, cellular, and Bluetooth connectivity built in.

What This Generator Keeps Running

5-ton central AC, electric water heater, electric range, electric dryer, refrigerator, freezer, dishwasher, furnace, sump pump, well pump, pool pump, every lighting circuit, home office, security: everything.

Limitations: A Level 2 EV charger on top of a 5-ton AC and other major loads. At that point, load management or the Protector series.

What It Actually Costs

Unit price

$8,159

Installed

$16,000–$25,000

$16,000–$25,000 installed; the premium end of residential standby. The 7329 bundle includes an ecobee thermostat and surge protection.

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How Loud Is It?

Approximately 67 dB: estimated from lineup pattern, not officially confirmed by Generac.

How Big Is It?

46.4" × 26.3" × 30.7" Next Gen enclosure, slightly different from the standard Guardian. 524 lbs.

Maintenance

Next Gen G-Force 1000 (999cc V-Twin) with hydraulic valve lifters: self-adjusting, one less maintenance item than the 22–26kW models.

Pros & Cons

Why it exists

✓Largest residential air-cooled from any brand: 28 kW LP / 25 kW NG
✓Built-in WiFi + cellular + Bluetooth: solves the connectivity issues
✓Next Gen engine with hydraulic lifters: self-adjusting valves
✓7329 bundle includes ecobee thermostat and surge protection
✓25 kW on NG is more whole-house capacity than most homes will use

Why most people don't need it

✗$16,000–$25,000 installed: most expensive residential Guardian
✗Noise level not officially confirmed (~67 dB estimated)
✗At this price, liquid-cooled commercial units enter the conversation
✗Overkill for homes under 3,500 sq ft
✗Next Gen enclosure is slightly larger: verify clearances

Frequently Asked Questions

Who needs a 28kW generator?▾

Homes above 4,000 sq ft with 5-ton AC, electric water heaters, electric ranges, and multiple heavy circuits. Also homes where the load calculation exceeds 26 kW and you want to stay in residential air-cooled.

Is the 28kW worth it over the 26kW?▾

Unit costs $1,170 more. You get 2 extra kW, built-in cellular monitoring (vs WiFi-only), and hydraulic lifters. If your loads genuinely need more than 26 kW, it's the only residential option. If not, the 26kW saves money.

What's the largest home a 28kW can power?▾

No hard sq ft ceiling: depends on what's inside. A 5,000 sq ft home with gas heat and 4-ton AC is well within range. A 3,500 sq ft all-electric home with EV charger and hot tub might push past it.

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