QuietCool Classic CL-4700 RF
A ducted Classic fan with a 10-year warranty for a typical home. It costs less up front than the Energy Saver but draws more power.
Amazon $1,109$1,109
The QuietCool Classic CL-4700 RF is the better whole house fan overall, rated 3.7 to 3.3. The QuietCool Classic CL-4700 RF leads on warranty, value and noise. The AirScape Sierra 3400 wins on efficiency and damper. The QuietCool Classic CL-4700 RF costs $940 less ($1,109 vs $2,049).
AirScape Sierra 3400
A premium ducted fan for a typical home in a cold or mixed climate, where the motorized R13 doors earn their cost.
HVACQuick $2,049$2,049
Prices were last checked November 2, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Which should you buy?
- Choose the QuietCool Classic CL-4700 RF for warranty (10-year warranty on the motor vs 3-year warranty on the motor), value ($343.34 per 1,000 CFM ($1,109, 3,230 CFM) vs $595.64 per 1,000 CFM ($2,049, 3,440 CFM)) and noise (49.4 dBA at high speed vs 52 dBA at high speed).
- Choose the AirScape Sierra 3400 for efficiency (11.5 CFM per watt vs 5.9 CFM per watt) and damper (R-13 insulated damper vs R-5 insulated damper).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every 3,001 to 5,000 CFM whole house fan; a clear win is highlighted. How we rank explains each one.
| Factor weight | QuietCool Classic CL-4700 RF | AirScape Sierra 3400 |
|---|---|---|
| Overall rating | 3.7/5 | 3.3/5 |
| Value 30% | 68 $343.34 per 1,000 CFM ($1,109, 3,230 CFM) | 29 $595.64 per 1,000 CFM ($2,049, 3,440 CFM) |
| Efficiency 20% | 15 5.9 CFM per watt | 100 11.5 CFM per watt |
| Noise 15% | 69 49.4 dBA at high speed | 60 52 dBA at high speed |
| Damper 10% | 33 R-5 insulated damper | 87 R-13 insulated damper |
| Warranty 25% | 100 10-year warranty on the motor | 22 3-year warranty on the motor |
Specifications
| QuietCool Classic CL-4700 RF | AirScape Sierra 3400 | |
|---|---|---|
| Airflow | ||
| Airflow, high speed | 3,230 CFM | 3,440 CFM |
| Power, high speed | 551 W | 298 W |
| Efficiency | 5.9 CFM/W | 11.5 CFM/W |
| Speeds | 2 | 10 |
| Noise | 49.4 dBA | 52 dBA |
| Install | ||
| Mount | Ducted | Ducted |
| Damper | R-5 insulated | R-13 insulated |
| Ceiling opening | 14.25 x 30.25 in | 22.5 x 26.5 in |
| Attic vent area needed | 5.9 sq ft | 4.6 sq ft |
| Voltage | 120 V | 120 V |
| Remote or wall control | Yes | Yes |
| App or remote monitoring | No | - |
| Warranty | ||
| Warranty | 10 years | 3 years |