CircuPool SmartFlo AF 3.9P
#2 in Large PoolsFull review
A high-flow smart pump for big pools with water features on a Pentair-footprint pad; most pools need less.
Amazon $1,875$1,875
The CircuPool SmartFlo AF 3.9P is the better pool pump overall, rated 3.6 to 3.2. The CircuPool SmartFlo AF 3.9P leads on efficiency and warranty. The Hayward TriStar VS 940 wins on controls.
Hayward TriStar VS 940
#11 in Large PoolsFull review
A 4 HP TriStar for large pools with heavy water-feature loads; for an ordinary pool a TriStar VS 900 or 950 uses less power.
Hayward (find a dealer)Prices were last checked October 27, 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 CircuPool SmartFlo AF 3.9P for efficiency (WEF 7.3, 39% above the ENERGY STAR minimum for its size vs WEF 6, 27% above the ENERGY STAR minimum for its size) and warranty (5-year warranty vs 3-year warranty).
- Choose the Hayward TriStar VS 940 for controls (Built-in schedule, optional wi-fi module, works with hayward omnilogic, hayward prologic, hayward aqualogic, hayward e-command 4, hayward oncommand, hayward omnix, pentair automation (universal comms), jandy automation (universal comms) vs Built-in wi-fi).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every large pools pool pump; a clear win is highlighted. How we rank explains each one.
| Factor weight | CircuPool SmartFlo AF 3.9P | Hayward TriStar VS 940 |
|---|---|---|
| Overall rating | 3.6/5 | 3.2/5 |
| Efficiency 35% | 58 WEF 7.3, 39% above the ENERGY STAR minimum for its size | 34 WEF 6, 27% above the ENERGY STAR minimum for its size |
| Value 25% | 62 $1,875 for 3.9 HP ($481 per HP) | 50 no current price (neutral score used) |
| Warranty 15% | 100 5-year warranty | 50 3-year warranty |
| Controls 15% | 35 Built-in wi-fi | 85 Built-in schedule, optional wi-fi module, works with hayward omnilogic, hayward prologic, hayward aqualogic, hayward e-command 4, hayward oncommand, hayward omnix, pentair automation (universal comms), jandy automation (universal comms) |
| Noise 10% | 50 noise not published (neutral score used) | 50 noise not published (neutral score used) |
Specifications
| CircuPool SmartFlo AF 3.9P | Hayward TriStar VS 940 | |
|---|---|---|
| Efficiency ratings | ||
| Pump type | In-ground (self-priming) | In-ground (self-priming) |
| Motor | Variable speed | Variable speed |
| Rated horsepower (DOE) | 3.9 HP | 4 HP |
| Hydraulic horsepower (DOE) | 1.8 HP | 2.3 HP |
| Weighted energy factor (WEF) | 7.3 kgal/kWh | 6 kgal/kWh |
| ENERGY STAR minimum for its size | 5.2 kgal/kWh | 4.7 kgal/kWh |
| ENERGY STAR certified | Yes | No |
| Pump | ||
| Voltage | - | 208/230 V |
| Speed range | - | 600 to 3,450 rpm |
| Maximum flow | - | 198 gpm |
| Pipe size | 2 in | 2 in |
| Size (W × D × H) | 23.8 × 10.9 × 12.8 in | - |
| Controls | ||
| Built-in schedule | - | Yes |
| Freeze protection | No | Yes |
| Wi-Fi | Built in | Optional module |
| App | - | Hayward OmniX |
| Automation compatibility | - | Hayward OmniLogic, Hayward ProLogic, Hayward AquaLogic, Hayward E-Command 4, Hayward OnCommand, Hayward OmniX, Pentair automation (Universal Comms), Jandy automation (Universal Comms) |
| Warranty and models | ||
| Warranty | 5 years | 3 years |
| Warranty terms | 5-year manufacturer warranty with US-based support, as listed for any buyer. | Sold only through pool pros: 3 years when sold by a Totally Hayward partner (sell sheet; the larger TriStar XL HCP3040VSP gets 4 years in residential use). Exclusions and other terms at hayward.com/expert. |
| Also sold as | LINGXIAO Relaax390-VS, Key Lander SWP390-VS, LX SWP390-VS, Iliving ILG8PP390-VS, Aqua Expert VSP39-Pro | - |
| Released | 2026-04 | 2025 |