Raypak Pool Heater H2O Sensor Fail Error Code

Updated 2026-08-29 · review status: manual-verified Last verified: 2026-08-29

Quick answer

Water-temperature sensors are open, shorted, or disagree.

Severity: high · DIY difficulty: intermediate

Safety

TBD - must be written per-code before publish

What H2O Sensor Fail means

Water-temperature sensors are open, shorted, or disagree.

Code meaning varies by series

  • X94 / SR-410 (Professional Series Digital): Water temperature sensors are open, shorted, or disagree.

Causes, ranked

  1. Causes not yet documented — verify against the service manual.

Parts & supplies for Raypak Pool Heater: filters, control boards, sensors, and common replacement parts.

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Sources

  • PoolDial error-code reference (manual-backed) — verified 2026-08-29
  • Raypak Professional Series X94 Installation & Operation Manual (241494), Table N Error Condition Messages — verified 2026-08-29