What to know
- Runs on hundreds of watts, not the thousands a central AC compressor draws — QuietCool's own marketing claims up to 50–90% off AC-related cooling usage, and even the conservative read is 'dramatically less.'
- Complete air exchange: flushes cooking odors, VOCs, and stale air out of the house — a genuine indoor air quality upgrade, not just cooling.
- Sized by the manufacturer's formula: 2–3 CFM per square foot of living space, with 1 sq ft of net-free attic vent area per 750 CFM — we measure both before quoting.
- The attic wins too: exhausting through the attic purges the 120°+ air that otherwise radiates into bedrooms all night.
- QuietCool's insulated, self-closing dampers seal the ceiling opening in winter, and the attic-hung fan head is quiet enough to sleep under.
How does a whole-house fan cool a home without AC?
It moves the cool air that's already outside through your house. Open a few windows, turn the fan on, and the QuietCool unit — mounted in the attic on an insulated duct, connected to a ceiling grille — pulls outdoor air in through the windows, through the living space, and out the attic vents. The U.S. Department of Energy describes exactly this: whole-house fans cool by air circulation whenever outdoor air is cooler than indoor air. Around Puget Sound that's almost every summer evening, which is why a fan alone carries many local homes through the season.
What size QuietCool does your home need?
QuietCool publishes a simple sizing formula — 2, 2.5, or 3 CFM per square foot of living space for a good, better, or best system — and a venting rule: 1 square foot of net-free attic vent area for every 750 CFM of fan capacity. The venting line is the one most homes fail, and an under-vented attic chokes the airflow you paid for. Our install starts by measuring both: square footage for the CFM target, then every gable, ridge, and soffit vent in your attic against the 1:750 rule (adding venting if needed).
- ≈1,600 sq ft rambler → roughly 3,200–4,800 CFM (STL PRO-4.8 class) and ~6.3 sq ft of net-free venting.
- ≈2,200 sq ft two-story → roughly 4,400–6,600 CFM — one large fan at the top of the stairs, or two zoned fans for room-by-room control.
- Larger or zoned homes → multiple smaller fans sized per zone, per QuietCool's zoning guidance.
Which QuietCool models does Eco install?
We install QuietCool's whole-house attic fan lines — the Stealth Pro and Trident Pro series — with the control setup that fits how you'll actually use it:
- Stealth Pro / Trident Pro fans with insulated, self-closing dampers that seal the ceiling when the fan is off — QuietCool publishes sound ratings roughly in the low-40s to low-50s dB range across the Pro lines, quiet enough to run overnight.
- Wall controls with countdown timers standard; QuietCool's Wi-Fi Smart Control adds app control, speeds, and run timers from 30 minutes to 12 hours.
- Manufacturer warranty: QuietCool backs its Professional-series fans with a published 15-year warranty — the paperwork stays with you.
- Clean electrical work on a dedicated switch or smart control, permitted as required.
When is a whole-house fan the wrong tool?
Honesty first — a fan is not for every moment or every home:
- Wildfire-smoke days: keep it off and windows closed — that's when AC or a heat pump plus filtration carries the load.
- Hot afternoons: it only helps when outside air is cooler than inside; DOE guidance is evenings, nights, and mornings — and never run it at the same time as your AC.
- Homes with combustion appliances need windows open during operation — a depressurized house can backdraft a water heater or furnace, which is part of why sizing and homeowner walk-through matter.
- Severe-allergy households should plan around high-pollen mornings (QuietCool sells filtration window screens, but managed expectations beat marketing).
Why pair it with air conditioning instead of replacing it?
A whole-house fan and AC are a team, not competitors. The fan handles the cheap cooling — evenings, nights, mornings — and pre-cools the thermal mass of the house so the AC starts the next afternoon from a lower baseline. The AC (or heat pump) handles heat-wave afternoons and smoke days when windows must stay shut. Homeowners who pair them run the compressor far fewer hours; that's the whole strategy.
Ready for the next step?
Talk to a licensed Eco pro — honest guidance and upfront pricing before any work begins.
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Common questions
Does a whole-house fan replace air conditioning in Seattle?
For many homes it covers most of the summer — our evenings cool off reliably. But heat waves and wildfire-smoke days need windows-closed cooling, which is why the fan + AC (or heat pump) pairing is the sweet spot: cheap outdoor-air cooling most days, mechanical cooling when it counts.
Is a QuietCool fan loud?
No — that's the point of the brand. QuietCool's fan head is suspended in the attic on an insulated duct, isolating motor noise from the living space, and the company publishes sound specs roughly in the low-40s to low-50s dB range across the Pro lines. Most homeowners describe it as a soft whoosh of moving air.
What does it cost to run compared to AC?
QuietCool's published Pro-line specs run from under 100 watts on low to several hundred on high — versus the several thousand watts a central AC compressor draws. QuietCool markets savings of up to 50–90% on AC-related cooling usage; your real number depends on your habits, so we'd rather show you the math for your home than promise a percentage.
Do whole-house fans work in winter?
They're a summer tool, and QuietCool's self-closing insulated dampers seal the ceiling opening when the fan is off so you don't leak heat in winter. Some homeowners also use short runs to flush the house after burnt-toast moments year-round.
What size fan does my home need?
QuietCool's formula is 2–3 CFM per square foot of living space, and your attic needs 1 sq ft of net-free vent area per 750 CFM so the air can actually get out. We measure your square footage and every attic vent, then recommend the right CFM model rather than guessing.
Can I run the fan and my AC at the same time?
No — that would pull your expensive conditioned air straight out through the attic. The playbook is alternation: fan when outside is cooler than inside (evenings through mornings), AC with windows closed when it isn't. DOE's whole-house fan guidance says the same.