Bradford-White Corp PE440T*F(BN,SX) Sequence of Operation, Power Up Sequence, Relay Energized

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Sequence of Operation

Note: The Sequence of Operation section is in addition to the Defender Atmospheric Service Manual, p/n 238-44943-00.

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 Flammable 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 relay, the gas control verifies the safety circuit to see if it is in the correct state. If the safety circuit is closed, the gas control LED flashes 2 times with a 3 second pause. The gas control waits 2 minutes. Then, the control cuts power to the relay. This cycle repeats until the safety circuit opens.

2.Relay Energized

3.Safety Circuit Check: If the safety circuit does not close within 30 seconds, the gas control LED flashes 3 times with a 3 second pause. The relay is powered for a maximum of 30 seconds every 2 minutes trying to close the safety circuit. This cycle repeats as long as there is a call for heat.

4.Hold Period (15 seconds)

5.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 deactivated. The relay will remain powered, and the gas control LED flashes 6 times with a 3 second pause.

6.Main Burner Ignition: After pilot flame is sensed, the gas control activates the main valve for main burner ignition. The gas control will ignore flame signals for 3 seconds to allow for the main burner to stabilize.

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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 SpecificationsControl Timings Sequence of Operation Power Up SequenceNormal Heating Sequence Relay EnergizedNormal Heating Sequence cont’d Abnormal Operation cont’d Temperature Sensor Fault Safety Circuit FaultTrial for Ignition 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 Maintenance Burner Cleaning ProcedureBurner Inspection 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 Thermal Well Testing Thermal Well Testing cont’dDetermine Water Temperature Inside Tank Determine Tank Temperature Determine Water Temperature Inside Tank cont’dSensor Resistance at Various Temperatures 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 WellGas Control Assembly Gas Control Assembly to the Thermal Well cont’dFlammable Vapor Sensor Testing Flammable Vapor Sensor Testing cont’d Flammable Vapor Sensor TestingRelay Replacement VAC Circuit TraceRelay Replacement cont’d Relay ReplacementCommon Terms Common TermsPart Name and Description Parts ListParts@bradfordwhite.com Techserv@bradfordwhite.com

PE4403S*F(BN,SX), PE440T*F(BN,SX), PE4503*F(BN,SX), PE2XR504T*F(BN,SX) specifications

Bradford-White Corporation is a renowned manufacturer of water heating and storage products, well-regarded for its commitment to quality and innovation. Among its diverse product lineup, the PE2XR504T*F(BN,SX), PE4503*F(BN,SX), PE440T*F(BN,SX), and PE4403S*F(BN,SX) models stand out for their technology, efficiency, and performance. These commercial electric water heaters are designed for demanding applications, making them ideal for various settings, including restaurants, hotels, and industrial facilities.

One of the most notable features across these models is the use of advanced heating elements, which are engineered to provide rapid recovery and consistent hot water temperatures. This capability ensures that businesses can rely on a continuous supply of hot water, particularly during peak demand periods. The tanks are constructed with high-quality materials that guarantee durability and longevity, reducing the need for frequent replacements.

Another key feature is the digital temperature control system, which allows users to easily set and maintain the desired water temperature with precision. This technology not only enhances user convenience but also contributes to energy efficiency, allowing businesses to operate within sustainable parameters while minimizing energy costs. Additionally, certain models are equipped with Bradford-White’s patented Hydrojet® Total Performance System, which promotes superior tank cleaning and reduces sediment buildup, thereby improving efficiency and prolonging the life of the heater.

Safety is paramount in the design of these units. The incorporation of advanced safety features, including a self-resetting thermal cutoff and a high limit switch, helps protect against overheating. Furthermore, these models are built with a robust insulation system, which reduces heat loss and improves overall energy efficiency.

In terms of versatility, the PE2XR504T*F(BN,SX), PE4503*F(BN,SX), PE440T*F(BN,SX), and PE4403S*F(BN,SX) can be easily integrated into existing plumbing systems. They are available in various capacities and configurations, catering to a wide range of commercial needs. With their combination of cutting-edge technology, reliability, and safety features, these Bradford-White models are an excellent investment for any commercial establishment seeking efficient and dependable hot water solutions.
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