Raypak XTherm Diagnostic Guide
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Raypak XTherm Diagnostic Guide
XTherm faults appear on the user interface and as a red PIM flash pattern. Record both before pressing RESET. A temporary error may clear when its condition is corrected; a safety lockout requires a manual reset after the underlying fault is repaired.
Safety: Disconnect electrical power and follow the manual before opening equipment. Gas, combustion, line-voltage, pressurized-water, and refrigerant work belongs to qualified service personnel.
Display error text
| Display or symptom | What it means | Manual-backed check |
|---|---|---|
| OUTLET SEN / LIMIT SEN / INLET SEN | A named temperature sensor or its circuit is faulty. | Check that sensor and its wiring. |
| GAS PRESS | The gas-pressure safety input is not in the expected state. | Check PIM wiring and the gas-pressure safety circuit. |
| IGNITION | The ignition sequence locked out. | Verify gas supply, transformer, igniters, and wiring; then press and release RESET. |
| LIMIT TRIP | Water temperature opened the high limit. | Confirm pump operation, water flow, limit setting, outlet sensor, and heat-exchanger condition. |
| FLAME | The control detected false flame. | Shut off gas, check gas-valve closure, clean burners and electrodes, then recycle power after repair. |
| ID CARD | The identity card is missing, incorrect, or not communicating. | Check that the proper card and its wiring are securely connected, then reset power and the system. |
| IGN CTRL | The PIM reports an internal control fault. | Reset power. Replace the PIM if the fault remains. |
| DELTA T | Inlet-to-outlet temperature rise exceeded the setpoint. | Check pump operation and flow across the heat exchanger. |
| LOW 24VAC | The 24 VAC supply is low. | Check supply wiring and transformer output; PIM operation requires more than 18.0 VAC. |
| BLOW SPEED | Blower speed is out of range. | Check line voltage, blower power, tachometer signal, wiring, and blower. |
| FLOW ERROR / UNDER FLOW / FLOW WARNING | Measured flow is absent, below the required operating point, or inconsistent with operating conditions. | Check pump operation, piping, strainers, valves, flow sensor, and required model-specific flow. |
PIM red LED flash codes
| Display or symptom | What it means | Manual-backed check |
|---|---|---|
| Steady red, green power LED off | Identity card fault. | Secure the proper ID card and perform power and system resets. |
| Steady red | Internal control fault. | Reset power and the system; replace the PIM if the fault remains. |
| 2 flashes | False flame. | Check gas-valve closure and clean the burner and electrodes. |
| 3 flashes | Ignition lockout. | Check gas supply, transformer, igniters, and wiring; reset the PIM and recycle power. |
| 4 flashes | Ignition proving-current fault. | Check the hot-surface igniter element and replace it if necessary. |
| 5 flashes | Low voltage. | Verify 24 VAC is above 18.0 VAC and replace the transformer if necessary. |
| 7 flashes | High-limit fault. | Check water flow, high-limit setting, and outlet sensor. |
| 8 flashes | Sensor fault. | Use the VERSA IC control to identify the sensor, then check it and its wiring. |
| 10 flashes | Water-pressure fault. | Check piping for leaks, the pressure switch if equipped, connections, and PIM J1 wiring. |
| 11 flashes | Blower-speed fault. | Verify line voltage, the tachometer signal, and J5 connections. |
| 13 flashes | High temperature-delta fault. | Check pump operation and flow across the heat exchanger. |
| 14 flashes | VERSA IC communication fault. | Check control operation and the cable between the PIM and VERSA IC. |
| 15 flashes | General limit-circuit fault. | Use the VERSA IC indication to identify the open limit. |
Source and model boundary
Source: Raypak XTherm 1005A–2005A Installation and Operation Manual, XTherm Error Codes and PIM LED Error Codes. This guide summarizes only the listed model family. Confirm the model number and use the current manufacturer manual before service.