Quietcool QC CL-4700 RF Classic Advanced Whole House Fan with Wireless Control - Up to 4415 CFM - Two Speed - Covers up to 2,208 SQFT - 10 Year Warranty - Removable Grille

Why I added a whole-house fan

After a couple of stubbornly warm nights on the second floor, I installed the QuietCool QC CL-4700 in my own home to see whether ventilation cooling could meaningfully reduce A/C use. Short version: it can—provided your climate and attic venting are up to the task. Over several weeks of evening and early‑morning operation, the CL-4700 consistently cleared out trapped heat, dropped indoor temps quickly, and kept the house comfortable well into the next day.

This model is rated at 4,415 CFM on high (3,402 on low), intended for homes up to about 2,200 square feet. My test space is a two‑story, ~2,000‑square‑foot home with decent soffit and ridge venting. The fan never felt underpowered, and I was surprised by how quiet it was for the airflow it moves.

Installation and setup

I handled the install solo with basic carpentry and electrical skills. Plan for 2–4 hours depending on attic access and how fussy you are about layout.

Highlights:
- Ceiling cutout: 14 x 30 inches for the intake grille and damper box. No joist cutting required if you’re on 16" or 24" on‑center framing.
- Mounting: The motor assembly hangs from the rafters, which keeps vibration off the ceiling and is a big part of why the unit runs quietly.
- Controls: The included wireless RF glass switch is excellent—no need to fish control wires. It offers two speeds and a countdown timer up to 12 hours.
- Power: Mine shipped with a plug, so I used an existing attic outlet. If you don’t have one, factor in an electrician visit.

One important pre‑check: attic venting. This fan wants roughly 5.89 sq ft of net free area (about 850 in²). That’s the sum of your ridge, gable, and soffit vents after accounting for screen reduction. If you’re short, add vents; starving the fan will reduce performance and can pressurize the attic.

Tip: Before cutting, bring a piece of cardboard cut to 14 x 30 inches into the attic and test-fit it between joists. It will save you grief locating a spot with good clearance and straight duct run.

Design and build

The CL-4700 is part of QuietCool’s “classic” style layout: a ceiling damper box with an intake grille, a length of insulated duct, and the motor/fan hanging remotely in the attic. Separating the motor from the ceiling opening reduces noise at the grille. The damper doors are insulated to R‑5 to help limit heat transfer when the fan is off, and the grille is removable for cleaning.

Fit and finish are solid. The damper box doors seal reliably, and the duct is robust enough to handle some repositioning during install. If you’re ordering by mail, check the damper box for squareness and smooth door movement right out of the packaging so you can correct or exchange before cutting your ceiling.

Cooling performance

Used as intended—when outdoor air is cooler than indoor—the CL-4700 moves a ton of air. A few patterns I’ve found most effective:

• Evening purge: Run on high with a few windows cracked 2–4 inches. Don’t open every window fully; target the rooms you want to cool. You’ll feel a strong, directed breeze, and the whole house temperature drops quickly.
• Overnight low: Once the peak heat is pushed out, low speed is often enough to maintain airflow while reducing energy use and noise.
• Morning pre‑cool: A 30–60 minute run just before sunrise can bank cool air, helping the house stay comfortable into the afternoon.

On hot-but-dry nights, I regularly replaced the indoor air in minutes and saw comfortable sleeping temps upstairs without touching the A/C. On cooler days, pre‑cooling kept the house in the high 60s/low 70s well into the afternoon.

Caveat: this is ventilation cooling. If the outside air is humid, smoky, or warmer than inside, don’t run it—it will just bring in that air.

Noise and comfort

Noise is impressively restrained for the airflow. At the grille, it’s a soft rush of air rather than a mechanical whine. In rooms adjacent to the intake, it sounds like a box fan behind a closed door. The motor, suspended from the rafters, doesn’t telegraph vibration through the ceiling. On low, it’s a pleasant white noise. If you’re sensitive to sound, you’ll likely be fine with this unit.

As with any whole‑house fan, door movement and hallway drafts happen at high speed. That’s a function of pressure and is a sign your windows aren’t open enough. Crack an additional window and it settles down.

Controls and smart use

The wireless glass switch pairs out of the box and lets you:
- Set a countdown timer (great for “run 30 minutes at bedtime”).
- Toggle speeds.
- Mount the control anywhere without fishing wires.

For more flexibility, I put the fan on a smart plug rated for the load and created schedules like: on at dusk for 90 minutes; off; on again predawn for an hour. Voice control is convenient, but the included RF control is good enough that I wouldn’t call smart integration necessary.

Energy use and cost

At 551 watts on high, the CL-4700 delivers roughly 8 CFM per watt. It’s not the most efficient motor tech on paper (ECM variable‑speed systems can do better), but in practice the cost to operate is low. At $0.20/kWh, an hour on high is about 11 cents. Compare that to several kilowatts for central air and the savings add up quickly during shoulder seasons.

Maintenance and durability

Maintenance is minimal:
- Pop the grille a couple times a season to vacuum dust.
- Periodically check damper operation; make sure the doors close fully when the fan is off.
- Confirm the suspension straps are taut and connections are sound.

A 10‑year warranty on the motor gives some peace of mind. I didn’t experience rattles or loosened hardware over the test period.

Safety and best practices

• Open windows before switching on the fan; never run it with the house closed up.
• Crack a few windows a small amount rather than throwing everything wide open. You’ll get more directed airflow and quieter operation.
• Close fireplace dampers and be mindful of combustion appliances—avoid backdrafting water heaters or furnaces.
• Use the included window locks if you’re worried about security or small children.
• Don’t add a screen over the ceiling grille; it will reduce airflow significantly.

Where it fits—and where it doesn’t

The CL-4700 shines in:
- Dry or temperate climates with cool nights.
- Homes with at least ~6 sq ft of attic venting or the ability to add more.
- Owners comfortable with occasional window management for best results.

It’s less ideal if:
- You live in persistently humid regions where nighttime temps don’t drop.
- Outdoor air quality is frequently poor.
- Attic access is tight and adding vent area isn’t feasible.
- You want the ultra‑fine control and highest efficiency of a variable‑speed ECM system.

The tradeoffs

What you get:
- Strong airflow and fast cooling for up to ~2,200 sq ft.
- Quiet, low‑vibration operation thanks to the remote motor design.
- Simple installation with a wireless control and no switch leg to run.
- A useful countdown timer and a removable grille.
- An insulated damper that helps in winter.

What you give up:
- Variable speed; it’s a two‑speed PSC motor (high/low).
- Absolute convenience—ventilation cooling still asks you to work with outside conditions.
- The need to verify or upgrade attic vent area before install.

Recommendation

I recommend the QC CL-4700 for homeowners in climates with cool evenings who want to cut A/C use, clear out trapped heat quickly, and keep bedrooms comfortable at night. Its combination of high airflow, surprisingly low noise, wireless controls, and straightforward installation makes it a practical upgrade. Just make sure your attic venting meets the requirement, plan a sensible window strategy, and use it when outside air is cooler and clean. If you need always‑on, set‑and‑forget cooling in hot, humid conditions, a whole‑house fan—this one included—won’t replace air conditioning. But for the right house and climate, the CL-4700 is an efficient, quiet workhorse that meaningfully improves comfort and lowers cooling costs.