Hayward Pool Pumps' HP Ratings Temporarily Confusing

If you recently bought a new Hayward 1 HP pool pump, and it arrives with a "0.85 HP" label on it, you'd be rightly confounded.  Did Hayward, or the store you bought it from, cheat you with a lower-powered pump?

The short answer: No.  It's the same pump as ever, and it has the same flow rate and energy consumption it had with the old label.  

The long answer is that the U.S. Department of Energy (DOE) fixed a point of ambiguity around how HP is measured for pool pumps and motors, so that they can be more directly compared to one another, and against efficiency standards they must meet.  

The most complete explanation of the difference that we found is actually published by another pool pump manufacturer, Pentair, in their "New DOE Rules: Why Hydraulic Horsepower Matters" white paper.  It's surprisingly detailed, with great examples so that even the curious non-engineer can learn quite a bit from it.  

Another great resource on this topic is Trouble Free Pool's page on "Pump DOE Regulations," which is aimed more at a homeowner that's repairing their own equipment. 

Under the hood, the two regulations that led up to this change in HP measurement were the 2017 efficiency standards for pool pumps, and the 2023 motor rule driving the relabeling.  

This isn't only affecting Hayward, though their June 9th, 2026 announcement is what put it on our radar.  All manufacturers are cycling through inventory with the old labels and included documents (manuals, etc.). The regulations have gradual rollout periods, with the final phase, covering smaller pumps, stretching to late 2027.  That's why we're seeing this now, despite the newest of these regulations being a couple of years old. 

The transition period does make comparing pumps a bit harder in the meantime, though.  While you'll be able to better compare HP ratings among pumps in the future, for now, it's useful to compare the Weighted Energy Factor (once again, TroubleFreePool is a great resource).  They compare WEF to how cars are rated for miles per gallon, and it comes down to how many gallons the pump can move with 1 kWh of energy.  

Ultimately, this is a change that will make pumps easier to compare, but for now, rest assured, they're the same thoroughly proven hardware, not the wrong pump shipped by mistake.  We can expect these mismatches to fade over the next year or so as old packaging cycles out.  

Affected Models

Source: Hayward "Important Notice Regarding Horsepower Ratings on Single-Speed & Two-Speed Pumps", June 2026 (Table 1)

*We (Poolaroo) are not sure why these two rows aren't the same as the others, but we chose to share exactly what Hayward gave us.