# Generator Decoded — Full Fact Digest

Research-based, spec-first reference for portable gas generators. No prices, no star ratings, every pick names an honest drawback. We do not physically load-test or sound-test generators ourselves — every figure is compiled from manufacturer spec sheets, published generator-sizing references, or documented engineering formulas (LRA sizing, inverse-square-law noise normalization), and cited as such.

## Home
Canonical: https://generator-decoded.pages.dev/
Generator Decoded exists to fix two specific confusions: generators are marketed on peak/surge watts, not the running watts that limit continuous use; and published noise (dB) ratings are measured at inconsistent, often unstated distances.

## Key Facts: Portable Generators
Canonical: https://generator-decoded.pages.dev/key-facts/
- "NSF"-style badge confusion equivalent for generators: the headline "starting watts" number is not the number that limits continuous use — that's "running/rated watts."
- Central AC sizing uses LRA (Locked Rotor Amps) × voltage × ~1.2 safety margin, not a fixed range.
- Noise dB(A) claims lack an enforced test-distance standard; 23 ft (7 m) is only an informal norm.
- Inverter generators are commonly noise-tested at 25% load; conventional generators at 50% load — an additional, often undisclosed inconsistency.
- Carbon monoxide from gasoline generators is odorless and can be fatal in minutes; always run outdoors, never in a garage even with the door open.

## The Startup Watt Index (dataset, v1.0)
Canonical: https://generator-decoded.pages.dev/startup-watt-index/
CSV: https://generator-decoded.pages.dev/startup-watt-index.csv (versioned: startup-watt-index-v1.0.csv)
License: CC BY 4.0. Twelve appliances with running watts, starting watts, surge multiplier, recommended generator sizing, motor type, and source:
- Refrigerator/freezer: 400-800W running, 1,200-3,200W starting (~3-4x).
- Sump pump 1/3 HP: 600-800W running, 1,300-2,900W starting.
- Sump pump 1/2 HP: 1,000-1,050W running, 2,150-4,100W starting.
- Well pump 1/2 HP shallow/jet: 900-1,500W running, 1,500-3,000W starting.
- Well pump deep-well submersible: 1,500-2,500W running, 2,000-6,000W starting.
- Window/portable AC: 1,200-1,500W running, 1,800-3,600W starting.
- Central AC (3-5 ton, LRA-based): 3,500-6,000W running, 7,000-18,000W starting (derived calculation, not a fixed range).
- Furnace blower motor: 500-800W running, 1,150-1,800W starting.
- Microwave oven: 1,000-1,700W running, 1,200-2,000W starting (minimal surge — not a motor load).
- Table saw 1.5-3 HP: 1,800-2,400W running, 3,600-6,000W starting.
- Air compressor 1-2 HP: 1,200-1,700W running, 3,000-4,500W starting.
- Electric pressure washer: 1,200-1,500W running, 2,500-4,500W starting.
All figures are planning ranges compiled from manufacturer guides and generator-sizing references, not lab measurements — surge varies by motor design, age, and ambient temperature.

## The Generator Noise Normalization Index (dataset, v1.0)
Canonical: https://generator-decoded.pages.dev/generator-noise-normalization-index/
CSV: https://generator-decoded.pages.dev/generator-noise-normalization-index.csv (versioned: generator-noise-normalization-index-v1.0.csv)
License: CC BY 4.0. Normalization formula: dB_at_23ft = claimed_dB + 20 × log10(claimed_distance_ft ÷ 23).
- Honda EU2200i: 57 dB at 23 ft (manufacturer spec, distance disclosed) → normalized 57.0 dB.
- Yamaha EF2000iSv2: 61 dB at 23 ft (manufacturer spec, distance disclosed) → normalized 61.0 dB.
- Westinghouse iGen2200: 52 dB at ~20 ft (manufacturer spec, distance disclosed) → normalized ~50.8 dB.
- Cummins Onan QG 2800i: 65 dB at 10 ft (manufacturer spec, distance disclosed) → normalized ~57.8 dB (raw claim overstates loudness at 23 ft by ~7 dB because it was tested much closer).
- Champion 3400 Dual Fuel: 64 dB, distance NOT disclosed → not computable.
- Generac GP2200i: 58 dB, distance NOT disclosed → not computable (third-party range ~50-70 dB depending on load/source).
- WEN 56235i: 51 dB at quarter load, distance NOT disclosed → not computable.
- DuroMax XP4400E: 69 dB at full throttle, distance NOT disclosed → not computable.
- Predator 3500i: 57 dB, distance and load NOT disclosed → not computable.
We did not measure any of these generators ourselves; normalization only corrects for distance, not tonal character or load-condition differences.

## Running vs Starting Watts
Canonical: https://generator-decoded.pages.dev/running-vs-starting-watts-generator/
Starting (surge) watts is the marketed headline; running (rated) watts limits continuous use. Motor-driven appliances surge 2-4x running watts; resistive loads barely surge. Size to your single largest starting-watt appliance, not the sum of all starting watts.

## How Many Watts to Run a Refrigerator on a Generator?
Canonical: https://generator-decoded.pages.dev/how-many-watts-to-run-a-refrigerator-on-a-generator/
~400-800W running, ~1,200-3,200W starting. Minimum generator: ~1,000W running / ~3,000-3,500W starting for the fridge alone.

## What Size Generator for a Well Pump?
Canonical: https://generator-decoded.pages.dev/what-size-generator-for-a-well-pump/
Shallow/jet 1/2 HP: 900-1,500W running, 1,500-3,000W starting. Deep-well submersible: 1,500-2,500W running, 2,000-6,000W starting — check the pump's nameplate LRA for a precise figure.

## What Size Generator for Central Air Conditioning?
Canonical: https://generator-decoded.pages.dev/what-size-generator-for-central-air-conditioning/
3,500-6,000W running, 7,000-18,000W starting depending on compressor LRA. Formula: LRA × voltage × 1.2. A 60A LRA compressor at 240V needs ~17,280 starting watts. Soft-start devices reduce required generator surge without changing the compressor's LRA rating.

## Why Generator dB Ratings Don't Match
Canonical: https://generator-decoded.pages.dev/why-generator-decibel-ratings-dont-match/
No enforced standard distance or load condition exists for dB(A) claims. 23 ft is an informal norm. Inverse-square law: doubling distance drops sound ~6 dB. Testing farther away under-reports real-world loudness at a typical distance.

## Is an Inverter Generator Quieter?
Canonical: https://generator-decoded.pages.dev/is-an-inverter-generator-quieter/
Generally yes, mainly because inverter generators throttle engine RPM down at light load while conventional generators run a fixed RPM regardless of load. "Inverter" alone does not guarantee a distance-stated, verifiable dB(A) claim.

## Can a Generator Damage Appliances?
Canonical: https://generator-decoded.pages.dev/can-a-generator-damage-appliances/
Undersized generators mostly fail to start a motor rather than damage it in one attempt; repeated stalled starts and unstable voltage/frequency from poorly regulated conventional units are the real risks. Never back-feed a home panel through a wall outlet — use a licensed electrician and a transfer switch.

## Why Is My Generator's Rated Wattage Lower on Propane?
Canonical: https://generator-decoded.pages.dev/why-is-my-generator-rated-wattage-lower-on-propane/
Dual-fuel generators typically produce ~10-20% less rated wattage on propane than gasoline due to propane's lower energy density. Always check both figures on the spec plate before sizing a motor-driven appliance on propane mode.

## How Far Should a Generator Be From a House?
Canonical: https://generator-decoded.pages.dev/how-far-should-a-generator-be-from-a-house/
Gasoline generators produce carbon monoxide, an odorless gas that can be fatal in minutes. Run outdoors only, away from windows/doors/vents, never in a garage even with the door open. Follow the specific unit's owner's manual for exact distance; a noise rating has no bearing on safe placement.

## Best Portable Inverter Generator
Canonical: https://generator-decoded.pages.dev/best-portable-inverter-generator/
Ranked by output and noise-spec verifiability: Honda EU2200i and Yamaha EF2000iSv2 both state load condition and 23 ft distance; Westinghouse iGen2200 and Generac GP2200i and WEN 56235i and Predator 3500i vary in disclosure. No prices or star ratings; price bands only.

## Best Dual-Fuel Generator
Canonical: https://generator-decoded.pages.dev/best-dual-fuel-generator/
Champion 3400 Dual Fuel, DuroMax XP4400E, Westinghouse iGen4500DF — all flagged for the propane de-rate and for unverified noise-test distance. No prices or star ratings; price bands only.

## Best Generator for Home Backup
Canonical: https://generator-decoded.pages.dev/best-generator-for-home-backup/
DuroMax XP12000EH, Generac GP8000E, DuroMax XP13000HX — sized for transfer-switch backup of multiple circuits, including central AC sizing guidance via LRA. No prices or star ratings; price bands only.

## How We Evaluate Generators
Canonical: https://generator-decoded.pages.dev/how-we-evaluate/
Research-based spec compilation and documented engineering formulas, not hands-on load or sound testing. No prices, no star ratings, always a downside named, no invented ASINs, no exact prices.

## Questions this site can answer
- What's the difference between running watts and starting watts on a generator?
- How many watts does it take to run a refrigerator / well pump / sump pump / central air conditioner on a generator?
- How do I calculate the starting watts for my central air conditioner using LRA?
- Why do generator noise (dB) ratings from different brands not match each other?
- What test distance are generator dB(A) claims measured at, and why does it matter?
- Is an inverter generator quieter than a conventional generator, and why?
- Can an undersized generator damage my appliances?
- Why is a dual-fuel generator's rated wattage lower on propane than gasoline?
- How far should a portable generator be from my house, and why?
- Which portable inverter, dual-fuel, or home-backup generator should I buy?