Hayward AC Voltage High/Low: Incoming Power Out of Range
This fault means the drive on a Hayward variable-speed pump measured its own incoming electrical supply and decided it was outside the window the motor is rated to handle safely.
High severityApplies to: Hayward TriStar VS, Super Pump VS, and EcoStar variable-speed pool pumps
What it means
Every AC motor has a rated voltage window, generally about 10% above or below its nameplate figure, and a variable-speed drive is built to check that window continuously rather than just trust the wiring. Hayward's EcoStar documentation shows what that looks like in practice on a 230V unit: the drive trips separately for voltage that has dropped below roughly 185 VAC and for voltage that has climbed above roughly 264 VAC, reported as two distinct faults rather than one generic error. Outside that range, a motor can overheat trying to compensate for low voltage or take excess stress from high voltage, so the drive would rather stop cleanly and report the cause than keep running and risk burning out its windings.
Momentary dips are common enough that this fault doesn't always point to a wiring defect at all. Central air conditioners, well pumps, and other high-draw equipment on the same service can pull the whole panel's voltage down for a second or two when they kick on, and if a pool pump's drive happens to be checking voltage at that exact moment, it can trip and stop even though the wiring feeding it is perfectly sound. That's part of why the first troubleshooting step is simply trying the pump again rather than assuming a repair is needed — a single trip that doesn't repeat is a very different situation from one that keeps recurring on a predictable pattern.
Likely causes
- Loose or corroded wiring connections at the pump's electrical disconnect or breaker
- An undersized breaker or wire run causing voltage drop under load
- A genuine utility voltage problem or an overloaded electrical panel
What you can check yourself
- Power-cycle the pump once to see if it was a momentary voltage blip
- Visually check that the disconnect box wiring looks tight and undamaged (with power off)
This code involves mains electrical supply and should not be diagnosed by opening live electrical panels yourself. Have a licensed electrician or pool professional measure actual voltage at the pump and check the circuit if the error repeats.
Sources
Related
- All Hayward error codes
- Hayward Drive Overheated — VS Pump
- Hayward Priming Failure — VS Pump
- Symptom: Heater or Pump Keeps Tripping the Breaker