Bradford-White Corp PE2XR504T*F(BN,SX) Abnormal Operation cont’d Temperature Sensor Fault

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Sequence of Operation

Abnormal Operation (cont’d)

2.Temperature Sensor Fault:

A)Temperature Sensor Open Circuit: The gas control immediately turns off all outputs and proceeds to flash 8 times then 3 times with a three second pause. The error self clears if the fault clears for at least 15 seconds.

B)Thermal well sensors not reading the same temperature within ±5.5°F: The gas control immediately turns off all outputs and proceeds to flash 8 times then 3 times with three second pause. The error self clears if the fault clears for at least 15 seconds.

C)Water Temperature in excess of ECO (Energy Cut Off) Limit: The gas control immediately turns off the pilot and main valves. The gas control LED proceeds to flash 4 times with a 3 second pause.

To reset the gas control, rotate the setpoint knob to the minimum setting for at least 6 seconds before returning to desired temperature setting.

3.Safety Circuit Fault:

A)Safety Circuit Failed to Close: The gas control proceeds to flash 3 times with a 3 second pause. The gas control waits 5 minutes, and then tries to energize the relay again.

B)Safety Circuit Failed to Open: The gas control proceeds to flash 2 times with a 3 second pause. The gas control waits 5 minutes, and then tries to de-energize the relay.

4.Trial for Ignition Fault:

A)Relay Fault During Trial: The gas control stops the trial for ignition. The gas control proceeds to flash 3 times with a 3 second pause. The gas control waits 5 minutes, and then tries to energize the relay again.

B)Flame Not Sensed: The gas control energizes the spark igniter attempting to light the pilot and prove flame. If flame is not sensed within 90 seconds, the spark igniter turns off, the pilot valve is closed. The gas control LED flashes 6 times then 1 time with 3 second pause. The control waits 5 minutes before repeating the ignition sequence.

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Contents Service Manual Table of Contents Page Page Introduction Bradford White Defender Safety SystemHow to Use this Manual How to Use this ManualSpecifications Specifications Control Timings Relay Energized Power Up SequenceSequence of Operation Normal Heating SequenceNormal Heating Sequence cont’d Trial for Ignition Fault Abnormal Operation cont’d Temperature Sensor FaultSafety Circuit Fault Abnormal Operation cont’d Flame Sensing Fault LED Status Control Status Probable Cause Service Procedure TroubleshootingTroubleshooting Gas Valve / Control Model LED Status Accessory Module Probable Cause Burner Inspection Burner MaintenanceBurner Cleaning Procedure Unscrew the burner from the main burner orifice Pilot Inspection, Testing, and Replacement Burner Cleaning Procedure cont’dPilot Inspection, Testing, and Replacement cont’d Pilot MaintenanceThermal Well Testing Determine Water Temperature Inside Tank Thermal Well TestingThermal Well Testing cont’d Sensor Resistance at Various Temperatures Determine Tank TemperatureDetermine Water Temperature Inside Tank cont’d Gas Control & Thermal Well Removal From Water Heater Component DisassemblyGas Control Removal From Thermal Well Gas Control RemovalGas Control Removal From Thermal Well cont’d Gas Control Assembly to the Thermal WellFlammable Vapor Sensor Testing Gas Control AssemblyGas Control Assembly to the Thermal Well cont’d VAC Circuit Trace Flammable Vapor Sensor TestingFlammable Vapor Sensor Testing cont’d Relay ReplacementRelay Replacement cont’d Relay ReplacementCommon Terms Common TermsPart Name and Description Parts ListParts@bradfordwhite.com Techserv@bradfordwhite.com