Jandy JXi pool heater fault messages
The JXi controller monitors several functions of the heater. If something goes wrong, it shows a FAULT message on the control panel on top of the heater. Jandy's Section 10.2 (Service Diagnostic Messages, p. 47) lists each message with its possible causes and remedies. The ignition control inside the heater also has an LED that flashes service codes (Section 10.3, p. 48). Reading it means opening the heater, so leave that to a technician.
Most faults come from the heater's safety controls (Section 1.8, p. 7). The water pressure switch shows Check Flow when there is not enough water pressure at the header inlet. Two high limit switches, at 135 °F (57 °C) and 150 °F (65 °C), close the gas valve if the water gets too hot. The flue temperature sensor stops combustion if the exhaust gets too hot. The ignition control shows an ignition fault after 3 failed attempts to light. Jandy says the heater then retries on its own after one hour. You can also reset it by turning the control OFF and back ON and selecting Pool or Spa (Section 8.2.2, p. 39).
Safety: Gas appliance. Jandy, if you smell gas: immediately switch off main gas supply, do not try to light any appliance, do not touch any electrical switch or use any phone in your building, and call your gas supplier from a neighbor's phone. This heater contains wiring that carries high voltage. Installation and service must be performed by a qualified installer, service agency or the gas supplier.
Jandy strongly recommends calling a qualified service technician to perform all service and repairs on the heater (Section 10.1, p. 46). The owner checks on each page below are only the ones Jandy's remedies list that you can do without opening the heater.
Codes and what they mean
- Fault CHECK IGN CONTROL· The heater tried to light 3 times and failed, so it stopped.
- Fault HIGH FLUE TEMPERATURE· The flue sensor saw too much heat at the exhaust, so the heater stopped burning.
- Fault HIGH LIMIT· Water in the heater got too hot, or a limit switch failed, so the gas valve closed.
- Fault CHECK FLOW· The heater is not sensing enough water pressure, so it will not fire.
Models covered
JXi 200, JXi 260, JXi 400. Check your rating plate to confirm your model.
Source: Jandy JXi Gas-Fired Pool and Spa Heater Installation & Operation Manual (H0574300 Rev M): What to do if you smell gas (p. 1), 1.8 Heater Components (p. 7), 6 Electrical warning (p. 32), 8.2.2 If Ignition Is Unsuccessful (p. 39), 10.1-10.3 Troubleshooting (pp. 46-48). Written by the DIY Error Codes team. DIY Error Codes is independent and not affiliated with or endorsed by Jandy.