Raypak Digital Ignition Diagnostic Guide
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Raypak Digital Ignition Diagnostic Guide
Raypak's Digital 206A-406A, Digital Low NOx ASME 207A-407A, Professional Atmospheric 408A, and Above-Ground 106A-156A manuals use the same atmospheric-heater diagnostic vocabulary. The Professional Series X94/SR-410 does not: its manual defines a newer error-message table with water-sensor, auxiliary-control, ignition-control, inducer, flue, and condensate faults. The sections below intentionally keep those controls separate.
Atmospheric-heater diagnostic readouts
These come from the status tables and control-logic flow charts for Digital, Low NOx, Professional 408A, and Above-Ground models.
| Display Reads | Manual-backed cause | Field check |
|---|---|---|
| "Sensor Failure," "Sensor Open," or "Sensor Short" | Temperature sensor out of range | Inspect the thermistor, wires, and connector at Terminal P1. Check resistance against the chart. Replace the thermistor if not within 10% of chart values; if okay, replace the circuit board. |
| "Water Sw Open" | Water flow/pressure switch issue | Verify water flow and pressure. Clean the filter or strainer before condemning the switch. |
| "Hi Limit 1 Fault" / "Hi Limit 2 Fault" | High limit switch open | Verify water flow, inspect the internal thermostat and bypass valve. On ASME units this is a manual-reset device — press the MODE button to reset. |
| "Rollout Sw Open" | Rollout sensor tripped | Check for a blocked heat exchanger or soot buildup, then press the manual reset button. |
| "Clock/Fireman Sw" | Fireman or remote switch in the safety loop is OFF | Check the fireman switch or remote control wiring for an open condition. |
| "Vent/Field Sw #1" | Vent switch open | Check connections to the board; if an extractor is installed, troubleshoot the extractor. |
| "Ignition Lockout" | Pilot flame not established, or lost during trial for main burner | Check power at the pilot valve, check for spark, and verify a clean pilot orifice with proper clearance from igniter to ground rod. |
| "Ignition Failure" | Gas supply or valve operation issue | Verify gas is reaching the heater and confirm valve operation. |
X94 / SR-410 error messages
The X94/SR-410 table below comes from its Error Condition Messages table and troubleshooting flow chart. Do not translate these messages through the atmospheric-heater table above.
| Display reads | Manual-backed cause | Field check |
|---|---|---|
| WPS Stuck Closed / Water Sw Open | The water-flow switch does not match the current operating state. | Verify pump operation, valve position, filter condition, and water flow before checking the switch. |
| H2O Sensor Fail | Water-temperature sensors are open, shorted, or disagree. | Inspect the water-sensor circuits and wiring before replacing a sensor or control. |
| Aux Ctrl Fault 2 / 3 / 5 / 6 / 8 | Digital-control ROM, RAM, analog-reference, multiplexer, or clock fault. | Record the exact number and follow the control-board diagnostic path in the current manual. |
| Ign Ctrl Fault 2 / 3 / 5 / 6 / 7 | Ignition-control ROM, RAM, analog, flame-sense, or execution fault. | Record the exact number and have the ignition-control circuit diagnosed by qualified service. |
| Hi Water Temp / Hi Limit 1 Fault / Hi Limit 2 Fault | Water exceeded 108°F or a high-limit circuit opened. | Stop heating and check actual temperature, circulation, limits, sensor operation, and bypass condition before reset. |
| Blocked Vent / Vent Temp Limit | The vent safety or vent-temperature limit is open. | Shut the heater down and have the vent path, switch circuit, and over-temperature cause inspected. |
| Air Flow Sw Open / Air Flow Sw Closed / Fan Lockout | The inducer airflow switch did not match the fan state; three fan-switch faults in one demand create lockout. | Check the inducer, switch, tubing, relay, and wiring before clearing the lockout. |
| Ignition Failure / Ign 60 min Delay / Ignition Lockout | Flame was not established within the permitted trial sequence. | Verify fuel type and supply, gas-valve operation, ignition wiring, igniter, grounding, and flame proving through qualified service. |
| MV Output Fault / Flame w/o CFH | The gas-valve output is wrong or flame is sensed with the valve closed. | Shut off gas and have the valve and ignition control inspected immediately. |
| Low Temp Lockout / Low Voltage | Water is below 36°F, or control supply is below 20 V. | Verify actual water temperature and have the low-voltage supply and transformer checked. |
| Flue Over Temp / Flue Sense Fail / Blocked Drain | The flue is too hot, its sensor failed, or the condensate-drain switch is closed. | Shut the heater down and have venting, sensor wiring, combustion, and condensate drainage inspected. |
| Fan RPM Fault | Actual fan speed differs from target by more than 500 RPM. | Check for obstruction, loose wiring, blower power, and motor-control operation through qualified service. |
| "EOL" at startup | The MODE button is stuck. | Check the MODE button for a stuck or jammed switch. |
Mechanical symptoms for the atmospheric models
| Symptom | Manual-backed checks |
|---|---|
| Harmonics or whining noise | Check U.G. (unitized gas valve) movement in hot water above 110°F. Look for debris or restriction in the water or gas line. Low flow can allow scale to form in the heat exchanger — check pool pH and total alkalinity. |
| Heater cycles on and off continuously | Clean or replace a dirty filter, raise a low pool water level, adjust the external bypass, or adjust an out-of-spec pressure switch. |
| Liming or scale forming in the exchanger | Correct pool water chemistry first. Inspect the bypass for movement and replace if none; replace the U.G. if it doesn't move when heated. |
| Sooting | Reduce high flow rates with a manual bypass valve (target 105-110°F outlet). Check U.G. movement, air starvation, improper venting, and insects or debris clogging burner intake ports. |
| Pilot outage or "weak flame" signal | Adjust low gas pressure, clean a restricted or dirty pilot, or replace a weak pilot generator. |
| Yellow, lazy flame | Adjust low gas pressure and clean burner intake ports of insects or debris. |
| Takes too long to heat pool or spa | Confirm the heater isn't undersized for the pool gallonage, reset the time clock for adequate filter run time, clean a dirty filter, and confirm the gas line/meter is sized correctly. |
| Leaking at well or heat exchanger, or brittle/leaking gasket | Overacid water is the most common cause — correct water chemistry and replace the affected part. A gasket that's overheated because the heater runs after the pump shuts off points to the pressure switch adjustment. |
Model Notes
- Digital 206A-406A and Digital Low NOx ASME 207A-407A share nearly word-for-word diagnostic readout tables; the ASME line adds manual-reset language on Hi Limit faults.
- Professional 268A-408A uses the same flow chart structure, routing "Sensor Failure," "Water Sw Open," and "Hi Limit Fault" through the same Diagnostic Readouts step.
- Professional Series X94/SR-410 has a separate control vocabulary, documents the "EOL" stuck-MODE-button condition, and stores 10 faults accessible from the front touchpad.
- Above-Ground 106A-156A covers both the P-106 and P-156 controls; the P-156 adds a full digital thermostat with the atmospheric Diagnostic Readouts structure.
Source: Raypak Digital 206A-406A, Digital Low NOx ASME 207A-407A, Professional Atmospheric 408A, Professional Series X94/SR-410, and Above-Ground 106A-156A installation and operation manuals. Confirm the rating-plate model and use the current manufacturer manual before service.