205.0 ACVMax Operation5.10 Manual Reset Hard LockoutsCode Lockout Message DescriptionE1 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 [99ºC]E5 Blower Speed Blower is not at correct speed or speed signal is not being receivedby 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 temperaturesensor circuit.E31 Supply Sensor Open An open circuit has been detected in the boiler supply temperaturesensor circuit.E43 Return Sensor Shorted A short circuit has been detected in the boiler return temperaturesensor circuit.E44 Return Sensor Open An open circuit has been detected in the boiler return temperaturesensor circuit.E47 Water Pressure Sensor Error Water pressure sensor is disconnected or broken.E80 Return > Supply Return temperature is higher than supply temperature.E87 External Limit Open An external manual reset limit has opened