Bradford-White Corp D4403S*F(BN, D4504S*F(BN, SX) service manual Normal Heating Sequence cont’d

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Sequence of Operation

Normal Heating Sequence (cont’d)

7.Steady State Operation: During steady state operation, the gas control monitors:

Thermostat Temperature Sensor: When the setpoint temperature is satisfied, the gas control is shutdown, and the damper is powered closed. The gas control LED flashes a short flash once every 4 seconds (Idle status code).

Damper Position: If the damper position is altered during a call for heat, the pilot and main valves are shutdown. The damper is powered open attempting to close the damper safety circuit. The gas control LED flashes 3 times with a 3 second pause.

Flame Sensor: If flame is lost, the pilot and main valves are shutdown. The damper is powered open. The gas control attempts to re-light the pilot 4 times. If unsuc- cessful, the damper is closed, and the gas control proceeds to a 5 minute lockout. The gas control re-attempts to light the pilot starting at Normal Heating Sequence #2.

8.Thermostat Satisfies: Gas control LED flashes once every 4 seconds.

9.Burner Off

10.Damper Powered Closed (15 seconds)

Abnormal Operation

1.Flammable Vapor Sensor Fault:

A)If the resistance is greater than 70,000 ohms: The gas control immediately turns off all outputs. The gas control waits and monitors resistance for 30 seconds. If the resistance is greater than 65,000 ohms after 30 seconds, the gas control proceeds to verify resistive delay for 2 minutes and flashes 7 times then 1 time with a three second pause. This process is repeated 5 times until the control either returns to normal operation or proceeds to flammable vapor lockout.

B)If the resistance is below 3000 ohms: The gas control immediately turns off all outputs and proceeds to flash 8 times then 1 time with a three second pause. The error self clears if the resistance returns to normal range for at least 15 seconds.

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Contents Service Manual Table of Contents Page Page Introduction Bradford White Defender Safety SystemHow the Safety System Works IntroductionHow to Use this Manual How to Use this ManualSpecifications Wiring Diagram Sequence of Operation Power Up SequenceDamper Powered Open Normal Heating SequenceNormal Heating Sequence cont’d Damper Safety Circuit Fault Abnormal Operation cont’d Temperature Sensor FaultTrial for Ignition Fault Abnormal Operation cont’d Flame Sensing Fault Troubleshooting Probable Cause Service ProcedureLED Status Control Status Probable Cause Service Procedure Burner Cleaning Procedure Burner MaintenanceBurner Inspection Right side inner door Main burner Orifice Burner Cleaning Procedure cont’d Pilot MaintenancePilot Inspection, Testing and Replacement Pilot Inspection, Testing and Replacement cont’d Damper Replacement Damper Removal & InstallationDamper Removal & Installation cont’d Thermal Well Testing Thermal Well TestingThermal Well Testing cont’d Determine Tank TemperatureDetermine Water Temperature Inside Tank Sensor Resistance at Various Temperatures Component DisassemblyGas Control & Thermal Well Removal From Water Heater Gas Control & Thermal Well Removal From Water Heater cont’d Gas Control RemovalGas Control Removal From Thermal Well Gas Control Assembly to the Thermal Well Gas Control AssemblyGas 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 Dip Tube Inspection and Replacement Dip Tube InspectionAnode Inspection and Replacement Anode InspectionRemove the Damper to Gain Access to the Flue Baffle Damper RemovalRemove the Damper to Gain Access to the Flue Baffle cont’d Inner Door Removal Procedure Inner Door RemovalInner Door Removal Procedure cont’d Inner Door Gasket ReplacementInner Door Gasket Replacement Procedure Inner Door Installation Inner Door Installation with GasketScreenLok Flame Arrestor Cleaning Procedure Arrestor CleaningDamper Relay Installation Damper Relay Installation Damper Relay Installation cont’dConnect the other ends of the relay harness, as shown Common Terms Common TermsParts List Part Name and DescriptionParts@bradfordwhite.com Techserv@bradfordwhite.com

SX), D4504S*F(BN, D4403S*F(BN specifications

Bradford-White Corp has long been a pioneering name in the water heating industry, and their D4403S*F(BN, D4504S*F(BN, and SX models represent the company’s commitment to delivering high-quality, efficient solutions for residential and commercial applications. These water heaters are designed with various user needs in mind, ensuring that homeowners and businesses can enjoy a reliable hot water supply whenever needed.

One of the core features of these models is their advanced water heating technology. Utilizing power venting systems, these units ensure efficient heat transfer while minimizing heat loss. This technology promotes energy efficiency and helps users save on their energy bills. The power vent system also allows for flexible installation options, accommodating different types of venting configurations, which is especially useful in homes with unique designs or limited space.

The Bradford-White D4403S*F(BN and D4504S*F(BN models are equipped with their state-of-the-art Hydrojet Total Performance System. This feature not only enhances the heater's overall performance but also reduces sediment buildup within the tank, which can significantly extend the unit's lifespan and maintain efficiency over time. Moreover, the patented Vitraglas® lining protects the inner tank from corrosion, further prolonging the life of the appliance.

Safety is a paramount consideration in Bradford-White's design philosophy. Each model includes a robust Flammable Vapor Ignition Resistance (FVIR) system, which helps prevent the ignition of flammable vapors that may be present in the vicinity of the water heater. This feature meets stringent safety standards and provides peace of mind to users.

In terms of energy specifications, both the D4403S*F(BN and D4504S*F(BN models are designed to meet or exceed efficiency standards, contributing to lower energy consumption and environmental impact. The SX model is particularly notable for its user-friendly digital display and controls, allowing for easy temperature adjustments and efficient operation monitoring.

In conclusion, Bradford-White Corp's D4403S*F(BN, D4504S*F(BN, and SX models are a testament to the company’s dedication to quality, safety, and efficiency in water heating technology. With their innovative features, user-friendly design, and long-lasting durability, these water heaters are well-suited to meet the ever-evolving demands of modern households and commercial settings alike. As homeowners and businesses continue seeking reliable hot water solutions, Bradford-White stands out as a trusted choice in the industry.
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