Last updated: March 2026

Guardian 24kW

Power: 24kW LP / 21kW NG
Installed Cost: $13,000–$18,000
Noise: 67 dB (57 dB exercise)
Weight: 455 lbs
Warranty: 5 years
Fuel: Dual-fuel (NG/LP)

Best for: Larger homes (3,000–3,500 sq ft), or NG homes wanting closer to true 22kW performance.

The 24kW sits in an interesting spot. It's only $440 more than the 22kW at the unit level, uses the same V-Twin engine, and bumps you from 22 kW to 24 kW on propane. It also includes Quiet-Test mode, which drops the weekly exercise run to 57 dB.

What This Generator Keeps Running

4-ton central AC (including startup surges), full kitchen, refrigerator, freezer, furnace, sump pump, well pump, home office, most lighting, CPAP.

Limitations: Multiple heavy 240V loads simultaneously on natural gas (21 kW) electric range + AC + dryer at the same moment.

What It Actually Costs

Unit price

$6,559

Installed

$13,000–$18,000

Unit is $440 more than the 22kW. Installed gap is about $1,000–$1,500. For 2 extra kW and Quiet-Test mode, that's a reasonable step-up.

Get Free Quotes for the Guardian 24kW

Get Free Quotes Not Sure on Size?

30 seconds. No phone call. No commitment.

How Loud Is It?

67 dB full speed / 57 dB Quiet-Test during exercise. That exercise noise is the quietest in the Guardian lineup and close to inaudible from next door.

How Big Is It?

Standard Guardian dimensions. 455 lbs: oddly lighter than the 22kW (466 lbs).

Maintenance

Same G-Force 1000 V-Twin as the 22kW. Identical maintenance.

Pros & Cons

Why you'd pick this over the 22kW

✓Quiet-Test at 57 dB makes weekly exercise nearly invisible to neighbors
✓Only $440 more than the 22kW at unit level
✓21 kW on NG gets closer to true 22kW performance than the 22kW itself on NG
✓PWRview ATS option with energy monitoring features

Why you might not

✗Same reported alternator issues as the 22kW (2021–2024 models); class action status unverified
✗Narrow value proposition: $1,000–$1,500 more installed for 2 kW and Quiet-Test
✗12.5% NG derating (24→21 kW) is on the higher end
✗If you need more than 24 kW, the 26kW is another $1,000–$2,000

Frequently Asked Questions

Is the 24kW worth it over the 22kW?▾

If you're on NG and want to close the derating gap, or if Quiet-Test mode matters for your neighborhood: yes. If neither applies, the 22kW at $1,000–$1,500 less is the better value.

What is Quiet-Test mode?▾

Runs the weekly exercise at reduced engine speed: 57 dB instead of 67 dB. Only applies to exercise, not outage operation. At 57 dB from 23 feet, neighboring houses measure about 45–47 dB.

Can a 24kW handle a 4-ton AC?▾

On propane (24 kW) yes, including startup surges. On NG (21 kW). it works but other heavy loads need to not be running at the same moment the compressor kicks on.

Get Pricing for Your Home

Connect with licensed installers in your area.

Get Free Quotes for the Guardian 24kW

30 seconds. No phone call. No commitment.

Based on verified specs. OffGrid Compare is independent: no brand deals, no manufacturer affiliations. Why we built this →