Bradford-White Corp U1TW40S*FRN Sequence of Operation, Power Up Sequence, Normal Heating Sequence

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Sequence of Operation

Power Up Sequence

1.Start-up: Upon power up, the gas control runs a safe start check with a typical delay of 5 seconds.

2.Flammable Vapor Verification: The gas control verifies that the Flamma- ble Vapor Sensor is in the proper operating range prior to energizing any components. If the sensor is within the proper range, the gas control resumes normal operation. If the Flammable Vapor Sensor is out of range, the gas control LED immediately flashes 7 times with a 3 second pause.

Normal Heating Sequence

1.Thermostat Calls for Heat: Prior to energizing the blower, the gas control checks the safety circuit to insure the circuit is open. In the safety circuit the pressure switch is normally open and the blower temperature switch is normally closed.

2.If the safety circuit is closed, the gas control waits 4 seconds, the gas control LED flashes 2 times with a 3 second pause. The gas control waits 2 minutes. Then, the blower runs for 30 seconds. This cycle re- peats until the safety circuit opens.

3.Blower energizes.

4.Pressure switch proves blower/vent system operation: If the pressure switch does not close within 30 seconds, the gas control LED flashes 3 times with 3 second pause. The blower runs for 30 seconds every 2 min- utes trying to get the pressure switch or blower temperature switch to close. This cycle repeats as long as there is a call for heat.

5.Blower pre-purge period (15 seconds).

6.Trial for Pilot Ignition (90 seconds): The gas control lights the pilot by activating the spark igniter and gas flow to the pilot burner. If flame is not sensed within 90 seconds, the spark igniter and gas flow are deacti- vated. The blower will post-purge, and the gas control LED flashes 6 times with a 3 second pause.

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Contents Service Manual Table of Contents Page Page Bradford White ECO-DEFENDER Safety System IntroductionIntroduction How to Use this Manual How the Safety System WorksHow to Use this Manual Tools Required for Service Tools RequiredSpecifications Vent Tables Gallon-40,000 BTU/hr Gallon-42,000 BTU/hrGallon-60,000 BTU/hr Wiring Diagram Control TimingsIgnition State Timing Power Up Sequence Sequence of OperationNormal Heating Sequence Normal Heating Sequence cont’d Abnormal OperationAbnormal Operation cont’d Sequence of Operation Sequence of Operation Troubleshooting Probable Cause Service ProcedureLED Status Control Status Probable Cause Service Procedure Troubleshooting Burner Maintenance Burner Cleaning ProcedureBurner Inspection Burner Cleaning Procedure cont’d Pilot Maintenance Pilot Inspection, Testing and ReplacementPilot 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 TestingBlower Testing Blower Replacement Blower InstallationBlower Removal Blower Temperature Switch Testing Blower Installation cont’dBlower Temperature Switch Testing Blower Temperature Switch Testing cont’d Switch SettingCommon causes for high Exhaust temperature Blower Temperature Switch Replacement Blower Temperature Switch ReplacementThermal Well Testing Thermal Well TestingDetermine Tank Temperature Thermal Well Testing cont’dDetermine Water Temperature Inside Tank Component Disassembly Sensor Resistance at Various TemperaturesGas Control & Thermal Well Removal From Water Heater Gas Control Removal Gas Control & Thermal Well Removal From Water Heater cont’dGas Control Removal From Thermal Well Gas Control Assembly Gas Control Assembly to the Thermal WellGas Control Removal From Thermal Well cont’d Gas Control Assembly to the Thermal Well cont’d Flammable Vapor Sensor Testing Flammable Vapor Sensor TestingVAC Circuit Trace VAC Circuit Trace Safety Circuit Voltage Trace Safety Circuit Voltage TraceRemove the Blower to Gain Access to the Flue Baffle Blower RemovalRemove the Blower to Gain Access to the Flue Baffle cont’d Dip Tube Inspection and ReplacementDip Tube Inspection Anode Inspection and Replacement Anode InspectionInner Door Removal Procedure Inner Door RemovalInner Door Gasket Replacement Inner Door Removal Procedure cont’dInner Door Gasket Replacement Procedure Inner Door Installation Inner Door Installation with GasketArrestor Cleaning ScreenLok Flame Arrestor Cleaning ProcedureCommon Terms Common TermsParts List Part Name and DescriptionParts@bradfordwhite.com Techserv@bradfordwhite.com

U1TW40S*FRN, U2TW65T*FRN, UTW450S60FR*N, U1TW60T*FRN, UTW465S60FR*N specifications

Bradford-White Corp has long been a reputable manufacturer in the water heating industry, known for delivering high-quality and reliable products. Among their diverse range of water heaters, the U1TW40S*FRN, U1TW50S*FRN, U1TW60T*FRN, UTW465S60FR*N, and UTW450S60FR*N models stand out for their advanced features and technologies designed to meet varying hot water demands.

The U1TW series, including the U1TW40S*FRN, U1TW50S*FRN, and U1TW60T*FRN models, are well-suited for residential applications. Each model provides different capacities, with the numbers referring to the gallon capacities. The U1TW40S*FRN offers 40 gallons, the U1TW50S*FRN 50 gallons, and the U1TW60T*FRN 60 gallons, making them ideal for households varying in size and hot water requirements.

These models are equipped with Bradford-White's advanced Vitraglas® tank lining, a unique feature that provides superior protection against corrosion and extends the unit's lifespan by ensuring the inner tank remains free from damage. Additionally, their efficient heating elements and optimal insulation minimize heat loss, enhancing energy savings.

The UTW series, specifically the UTW465S60FR*N and UTW450S60FR*N, feature innovative technologies such as a durable stainless steel construction that offers robust performance while resisting the harmful effects of rust and degradation. This is particularly beneficial in areas with hard water, where mineral buildup can be problematic.

Each unit incorporates Bradford-White's signature HydroBurner® technology, which enhances combustion efficiency, ensuring that the water is heated quickly and consistently. This technology also helps in reducing greenhouse gas emissions, addressing environmental concerns while maintaining optimal performance.

In terms of ease of use, all models come with user-friendly controls that allow for easy temperature adjustments and monitoring, ensuring that users can customize their hot water needs conveniently. Additionally, features such as intuitive diagnostics enable quick troubleshooting, reducing downtime and maintenance efforts.

In conclusion, Bradford-White’s U1TW and UTW series water heaters are engineered to offer efficiency, durability, and user-friendly operation. With their advanced technology, excellent insulation, and robust construction, these models are a solid choice for anyone looking to invest in reliable hot water solutions for their home. Whether for a busy family or more modest hot water needs, these units provide peace of mind and consistent performance.
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