Jandy JXi and JXiQ heaters show text messages like CHECK FLOW or HIGH LIMIT, not number codes. Many point to low water flow, gas supply, or a sensor. Lucent Pools repairs Jandy heaters across DFW. Call 817-339-6770.
Based in Dallas–Fort Worth, serving Fort Worth and most of the Metroplex.
We repair pool heaters in Fort Worth, Frisco, and Lewisville, and we service most of the DFW Metroplex.
We repair in-ground pools and in-ground spas. We do not repair portable hot tubs.
If you smell gas, don't light any appliance and don't touch electrical switches or use a phone in the building. Call your gas supplier from a neighbor's phone, or the fire department if you can't reach them. Jandy says heater service and repairs should be done by a qualified service technician. Never open the gas valve, burner or any gas part yourself.
What does CHECK FLOW mean on a Jandy heater?
The heater's water pressure switch isn't sensing enough water flow, so it won't fire. Usually the pump is off or slow, the filter or baskets are dirty, or a valve is closed.
Jandy JXi manual H0574300, Section 10.2, shows CHECK FLOW. The JXiQ manual H0780200, Section 11.2, shows it as CHECK H2O FLOW.
You can check that the pump is running and primed, the filter and baskets are clean, the valves are open, the return eyeball fittings are in place, and a variable-speed pump is not set too low. If it still shows, the pressure switch may need adjusting or replacing. That is a job for a technician. See pool pump repair and pool filter repair.
What does FAULT – HIGH LIMIT mean?
Water inside the heater got hotter than its safety limit, so the heater shut the gas off. Common causes are low water flow, a blocked vent, or a failed limit switch.
The JXi manual cites the first-pass and outlet high-limit switches. Check flow first. On a JXiQ the message is HIGH LIMIT SWITCH: a technician checks for anything restricting flow to the heat exchanger. If HIGH LIMIT comes back, call.
What do FAULT – HIGH FLUE TEMPERATURE and CHK HEAT EXCHANGER mean?
The exhaust is running too hot. Jandy says to have a service professional review it. Common causes are a blocked vent, low flow, or soot or scale on the heat exchanger.
On a JXi the message is HIGH FLUE TEMPERATURE. On a JXiQ the messages are HIGH FLUE TEMP and CHK HEAT EXCHANGER. CHK HEAT EXCHANGER means the flue stayed over 400° for more than 5 minutes. You can keep the vent clear of leaves and nests. The rest is work for a technician. Scale builds when chemistry is off. See residential pool maintenance.
Why won't my Jandy heater ignite? (CHECK IGN CONTROL and ignition lockout)
The heater tried to light and couldn't prove a flame. Jandy lists a broken igniter, low gas supply, a fan or air-switch problem, or a wiring fault. After three failed tries the heater locks out.
On a JXi the message is FAULT – CHECK IGN CONTROL. On a JXiQ the messages are IGNITION CONTROL LOCKOUT, FLAME SIGNAL FAIL/WEAK, LOW GAS PRESSURE, and CHECK AIR FLOW/AIR SWITCH.
Make sure other gas appliances work and the propane tank isn't empty. Don't turn gas valves or open the heater; call us or your gas company.
We repair and replace gas and propane pool heaters. Gas line work, including new runs and changes to existing lines, is done by our licensed gas contractor, with permits where required.
Also keep the intake and the vent clear. Everything inside the heater: call.
What do the LED flashes on the Jandy ignition control mean?
Steady on means an ignition control fault, one flash is an air flow fault, three flashes is ignition lockout after three failed tries. Two flashes means flame is present with no call for heat: turn the heater off and call a pro. A technician reads these LED codes inside the heater. Don't remove panels.
Jandy JXi manual H0574300, Section 10.3, lists the four LED codes in these words.
| LED Code | Fault Description |
|---|---|
| The LED light is on continuously. | Ignition Control Fault. Refer to qualified service personnel. |
| LED single flash. | Air flow fault. |
| LED double flash. | Flame exists when there is NO call for heat. Refer to qualified service personnel. |
| LED triple flash. | Ignition lockout (heater has made three (3) unsuccessful attempts to fire and is in a soft lockout condition). |
On a JXiQ the board LEDs are status lights for power and communication, not fault codes. Read the display message instead (Jandy JXiQ manual H0780200, Section 11.3).
What do the sensor and wiring messages mean?
The heater's control can't read a temperature sensor correctly, usually because of a failed sensor or a loose or reversed wire. These need a technician with a meter.
On a JXi the messages are SHORTED H2O SENSOR and OPEN WATER SENSOR. On a JXiQ the messages are CHK IN/OUT H2O SENSOR, CHECK FLUE SENSOR, CHECK H2O WIRING, CHECK FLUE WIRING, REPLACE MAIN BOARD, and CHK PWR GAS VALVE. UNEXPECTED FLAME: turn the heater off and call.
NO GRD CONNECTION and L/N WIRES REVERSED: call a technician. We repair anything electrical on your pool, from pumps, heaters, and automation to timers, salt systems, and pool lights, and connect or disconnect it on your existing circuits.
Messages that aren't a fault: FAULT – PUMP, AUX Monitor, VersaFlo, louver
Some messages are status notes, not breakdowns. FAULT – PUMP on a JXi is normal when the heater is in Maintain Temp mode and the filter pump is off.
AUX Monitor on a JXi means check the VersaFlo bypass. On a JXiQ, CHECK AUX MONITOR, CHECK VERSAFLO, and CHECK LOUVER are jumper or feature settings for a technician. TEMP RISE LOW/HIGH means flow through the heat exchanger is too high or too low.
iAquaLink or other automation shows heater status.
How do I reset a Jandy heater, and is it safe to keep resetting it?
Turn the control off and back on, then select Pool or Spa. If the same message returns, stop and call.
Never reset after a two-flash LED or UNEXPECTED FLAME code: turn the heater off and call.
Older Jandy heaters (LXi, Lite2, LX/LT)
Older Jandy models use different messages than the JXi and JXiQ. Note the exact message and the model on the rating plate, and call; we repair older Jandy heaters too.
We service and repair all pool equipment brands, including Jandy, Pentair, and Hayward. We are an Authorized Jandy ProEdge Warranty Station and can also help with Pentair and Hayward warranty claims.
When to call a pro
Check flow, power, gas supply and the vent yourself. Anything inside the cabinet, any gas part, and any message that returns after those checks is a job for a technician.
| You can check | Call a technician |
|---|---|
| Pump running, filter and baskets clean, valves open (CHECK FLOW) | CHECK FLOW that stays after those checks |
| Heater on, POOL or SPA selected, set point above the water temperature | HIGH LIMIT, HIGH FLUE or CHK HEAT EXCHANGER that comes back |
| Other gas appliances work, propane tank not empty, vent and air intake clear of leaves or nests | Ignition lockout, flame-signal or low-gas messages, or anything that needs a panel removed |
| Turn the control off and on once, then select POOL or SPA | The same message after one reset |
| FAULT – PUMP while in Maintain Temp mode is normal | Any sensor, wiring, ground, main board or UNEXPECTED FLAME message (turn the heater off) |
Don't open the heater or touch gas parts.
Repair or replace a Jandy heater?
Most error messages point to a part that can be repaired or replaced: an igniter, sensor, switch or board. Replacement makes sense when the heat exchanger has failed or repairs keep stacking up.
When replacing, we usually recommend Jandy. The customer chooses. The reason is the 3-year warranty on new Jandy equipment we install.
See pool heater repair in Fort Worth and DFW. See pool repair in Fort Worth and DFW.
Is my Jandy heater still under warranty?
Check your install paperwork, and the model and serial number on the rating plate. We are an Authorized Jandy ProEdge Warranty Station and can also help with Pentair and Hayward warranty claims. Repair workmanship is covered for 90 days. Parts carry their manufacturer's warranty, and new Jandy equipment we install carries a 3-year warranty through our Jandy ProEdge status.
The rating plate shows the model and serial number, not the install date (Jandy JXi manual H0574300, Section 1.3).
- 25+ Years in the Pool Business
- Lucent Pools is insured.
- Authorized Jandy ProEdge Warranty Station
- Lucent Pools is CPO certified by the Pool & Hot Tub Alliance (PHTA).
More help: pool repair in Fort Worth and Dallas–Fort Worth, pool repair in Frisco, pool repair in Lewisville.
Need a Repair?
What a repair costs depends on the part; we price it after diagnosis. Call 817-339-6770. Monday through Friday, 8:00 AM to 6:00 PM. Saturday closed. Sunday closed.
