Bradford-White Corp U4TW60T*FRN Determine Tank Temperature, Thermal Well Testing cont’d

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Determine Tank Temperature

Thermal Well Testing (cont’d)

Determine the correct resistance values using the Determine the Water Temperature Inside the Tank procedure on page 23. If the values are correct, replace the gas con- trol, otherwise replace the thermal well.

Determine Water Temperature Inside Tank

WARNING

Stored water may be HOT when performing the following steps in this procedure. Take necessary precaution to pre- vent personal injury.

Note: It is important to understand once the resistance for the thermal well is deter- mined using the Thermal Well Testing Procedure on page 21, water flow through the water heater should not occur. Prior to performing the steps below, turn off the cold water supply to the water heater. This will prevent cold water flow into the tank affect- ing the resistance value of thermal well.

Step 1. Move the gas control power switch to the “OFF” position.

Gas control power

switch

Step 2. Draw approximately 4 gallons of water from the drain valve into a con- tainer and discard. Draw an additional gallon and immediately measure the water tem- perature using an accurate thermometer. It may be necessary to open a hot water fau- cet to allow heater to drain.

Step 3. Using the chart on page 23, determine the correct resistance value for the water temperature from Step 2.

Example: If temperature of water is 84°F, then the resistance through the sensor

would be 8449 (see shaded area). NOTE: Sensor resistance increases as the tem- perature falls.

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Contents Service Manual Table of Contents Page Page Introduction Bradford White ECO-DEFENDER Safety SystemHow the Safety System Works How to Use this ManualTools Required Tools Required for ServiceSpecifications Gallon Vent TablesSpecifications Control Timings Wiring DiagramNormal Heating Sequence Power Up SequenceSequence of Operation Abnormal Operation Normal Heating Sequence cont’dAbnormal Operation cont’d Sequence of Operation Sequence of Operation LED Status Control Status Probable Cause Service Procedure TroubleshootingTroubleshooting Troubleshooting Burner Inspection Burner MaintenanceBurner Cleaning Procedure Burner Cleaning Procedure cont’d Pilot Inspection, Testing and Replacement Pilot MaintenancePilot Inspection, Testing and Replacement cont’d Page Pressure Switch Testing Pressure Switch TestingPressure Switch Testing cont’d Pressure Switch Replacement Pressure Switch ReplacementBlower Testing Blower TestingPage Blower Removal Blower ReplacementBlower Installation Blower Temperature Switch Testing Blower Temperature Switch TestingBlower Installation cont’d Switch Setting Blower Temperature Switch Testing cont’dBlower Temperature Switch Replacement Blower Temperature Switch ReplacementThermal Well Testing Thermal Well TestingDetermine Water Temperature Inside Tank Determine Tank TemperatureThermal Well Testing cont’d Gas Control & Thermal Well Removal From Water Heater Component DisassemblySensor Resistance at Various Temperatures Gas Control Removal Gas Control Removal From Thermal Well cont’d Gas Control AssemblyGas Control Assembly to the Thermal Well Gas Control Assembly to the Thermal Well cont’d Flammable Vapor Sensor Testing Flammable Vapor Sensor TestingVAC Circuit Trace Safety Circuit Voltage Trace Safety Circuit Voltage TraceBlower Removal Remove the Blower to Gain Access to the Flue BaffleDip Tube Inspection Remove the Blower to Gain Access to the Flue Baffle cont’dDip Tube Inspection and Replacement Anode Inspection Anode Inspection and ReplacementInner Door Removal Inner Door Removal ProcedureInner Door Gasket Replacement Procedure Inner Door Gasket ReplacementInner Door Removal Procedure cont’d Inner Door Installation with Gasket Inner Door InstallationScreenLok Flame Arrestor Cleaning Procedure Arrestor CleaningCommon Terms Common TermsPart Name and Description Parts ListParts@bradfordwhite.com Techserv@bradfordwhite.com