Raypak Pool Heater Flue Over Temp / Flue Sense Fail / Blocked Drain Error Code

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

Quick answer

The flue is too hot, its sensor failed, or the condensate-drain switch is closed.

Severity: high · DIY difficulty: intermediate

Safety

TBD - must be written per-code before publish

What Flue Over Temp / Flue Sense Fail / Blocked Drain means

The flue is too hot, its sensor failed, or the condensate-drain switch is closed.

Code meaning varies by series

  • X94 / SR-410 (Professional Series Digital): Flue Over Temp: heater shut off because flue temperature is too high. Flue Sense Fail: flue monitor enabled and flue temperature sensor open or shorted. Blocked Drain: condensate drain switch is closed.

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