Modern boilers are equipped with sensors and elements, which control their functioning. They activate protective mechanisms, which, in turn, prevent things from getting worse. If a malfunction does occur, please, check the table and troubleshoot it.
| Code | Lockout Message | Description |
|---|---|---|
| E1 | Failed Ignition | The burner failed to light after 5 ignition attempts. |
| E2 | False Flame | A flame is being detected prior to ignition. |
| E3 | High Boiler Temperature | Boiler temperature has reached 210?F [99?C] |
| E5 | Blower Speed | Blower is not at correct speed or speed signal is not being received by control module. |
| E8 | Flame Circuit Error | Flame circuit test failed. |
| E9 | Gas Valve Circuit Error | Gas valve circuit test failed. |
| E13 | Reset Limit Reached | Resets are limited to 5 every 15 minutes. |
| E15 | Sensor Drift | Supply or return sensor reading has drifted. |
| E16 | Supply Sensor Stuck | Supply sensor reading is not changing. |
| E17 | Return Sensor Stuck | Return sensor reading is not changing. |
| E18 | Sensor Failure | Supply or return sensor reading changed very rapidly. |
| E21 | Internal Control Fault | A / D conversion error. |
| E30 | Supply Sensor Shorted | A short circuit has been detected in the boiler supply temperature sensor circuit. |
| E31 | Supply Sensor Open | |
| E43 | Return Sensor Shorted | |
| E44 | Return Sensor Open | |
| E80 | Return > Supply | Return temperature is higher than supply temperature. |
| E87 | External Limit Open | An external manual reset limit has opened |
| E7 | High Flue Temperature | Flue temperature exceeds high limit. |
| E12 | Internal Control Fault | EEPROM misconfiguration |
| E25 | Internal Control Fault | CRC check error. |
| E32 | DHW Sensor Shorted | A short circuit has been detected in the DHW temperature sensor circuit. |
| E33 | DHW Sensor Open | An open circuit has been detected in the DHW temperature sensor circuit. |
| E34 | Low Voltage | Line voltage has fallen below an acceptable operating level. |
| E37 | Low Water | Water level has fallen below an acceptable operating level. |
| E45 | Flue Sensor Shorted | A short circuit has been detected in the boiler flue temperature sensor circuit. |
| E46 | Flue Sensor Open | An open circuit has been detected in the boiler flue temperature sensor circuit. |
| E76 | External Limit Open | An external automatic reset boiler limit has opened. |
| E81 | Sensor Drift | Supply and return temperatures are not equal. |
| E89 | Incorrect Setting | A parameter setting is in conflict with another setting. |
| E90 | Firmware Mismatch | Control module and display firmware versions are incompatible. |
| E91 | System Sensor Shorted | A short circuit has been detected in the system temperature sensor circuit. |
| E92 | System Sensor Open | An open circuit has been detected in the system temperature sensor circuit. |
| E93 | Outdoor Sensor Shorted | |
| E94 | Internal Display Fault | Display memory error. |
| E95 | Supply Sensor Error | Supply sensor reading is invalid. |
| E96 | Outdoor Sensor Open | An open circuit has been detected in the outdoor temperature sensor circuit. |
| E97 | Cascade Mismatch | Cascade configuration has changed. |
| E98 | Cascade Bus Error | Communication with other boilers has been lost. |
| E99 | Controller Bus Error | Communication between boiler display and control module has been lost. |