Jandy Pool Heater FAULT-SHORTED H2O SENSOR Error Code

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

Quick answer

Shorted Water Temperature Sensor Water temperature sensor circuit shows a short. Faulty wiring or connection, failed water temperature sensor. Inspect sensor wiring at the Power Interface Board (PIB). Check sensor connection. Replace sensor if faulty.

Severity: high · DIY difficulty: intermediate

Safety

TBD - must be written per-code before publish

What FAULT-SHORTED H2O SENSOR means

Shorted Water Temperature Sensor Water temperature sensor circuit shows a short. Faulty wiring or connection, failed water temperature sensor. Inspect sensor wiring at the Power Interface Board (PIB). Check sensor connection. Replace sensor if faulty.

Code meaning varies by series

  • JXi 200/260/400 & LXi 250/400: FAULT-SHORTED H2O SENSOR: water temperature sensor circuit reads shorted - faulty wiring/connection or failed sensor. Heater will not fire.

Causes, ranked

  1. 1. Faulty wiring or connection. occasional pro-only

    Check:

    Fix:

  2. 2. Failed water temperature sensor. occasional pro-only

    Check:

    Fix:

Parts & supplies for Jandy 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
  • Jandy JXi Gas-Fired Pool and Spa Heater Installation & Operation Manual (Section 10.2 Service Diagnostic Messages, 10.3 Ignition Control LED Service Codes) — verified 2026-08-29
  • PoolDial Jandy JXi troubleshooting guide (fault-code table) — verified 2026-08-29