Bradford-White Corp PDV80T300, D80T725, D65T625, PDV100S150, PDV100S250 Sequence of Operation

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WIRING DIAGRAM

Sequence of Operation

1Thermostat calls for heat:

.

The relay closes on the control board, sending line voltage (115-120 volts) from “inducer” terminals #5 and 3 on the control board to the induced draft blower.

2The blower starts and when sufficient vacuum is achieved, the pressure switch closes and completes the 24 volt circuit between terminals 1 and 3 on the Control Plug to the the board, allowing the ignition sequence to proceed. The blower “purges” any remaining combustion products from the previous cycle for 15 seconds before allowing the pilot to light. This is the pre-purge period of the ignition cycle.

3Trial for ignition (three 90 second ignition trials, with 75 second pauses between trials).

Control Board simultaneously sends:

1.24 volts from control pin terminal #8, to “MV/PV” terminal of gas valve (common terminal).

2.24 volts from control pin terminal #2, to “PV” terminal of gas valve to establish

gas flow at pilot.

3.Low current high voltage from “spark” terminal, to generate spark at the pilot and ignite pilot gas flow.

4.Pilot flame proving signal (measured in micro-amps). from the “sense” terminal, to prove pilot flame.

4Once pilot flame is proven, sparking will stop.

Once sparking stops, 24 volts is sent from control pin

5terminal #5 on control board, to “MV” terminal on gas valve to establish main burner gas flow. Main burners ignite from the pilot flame.

The control board constantly monitors pilot flame through the flame sensor rod. If pilot flame is lost, pilot and main burners are shut down. After a 75 second inter-purge period, the control will attempt to re-light the pilot beginning at sequence 3 above.

Main burner fires until the thermostat is satisfied. The control

7board interrupts 24 volts through the gas valve circuit. Pilot and main burners are turned off.

8The induced draft blower shuts off 5 seconds after the gas valve closes. This is the post-purge period.

LOCKOUT CONDITION

Control board will go into “Soft Lockout” if the pilot cannot be lit after 3 ignition trials. The water heater display indicates a lockout condition by showing an error code number (62 or 63) with “Service Needed” in the display window. Refer to error codes in the diagnostic section of this Service Manual. In a “Soft Lockout” condition,

the control will wait for 60 minutes and then make 2 more attempts to light the pilot and establish the main burners.

Soft lockout reset is accomplished by depressing the lower right button under “Reset” for 3 seconds.

If the water heater should reach 200 degrees F, then the high limit control will shut off the burners and the water heater will go into a “Hard Lockout”. Error code 65 will be shown in the water heater display. The control can only be reset in the “service mode”, which is detailed in the next section of this Service Manual.

If the exhaust or intake terminals become blocked during operation or if the blower motor fails, the pressure switch will open and error code 29 will appear in the display. When the condition is corrected, the error code will disappear and the water heater will resume normal operation. No resetting of the control display is needed for the pressure switch error code.

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Contents Service Manual Table of Contents Features of Induced Draft Models Features of PDV-S Model SeriesFeatures of PDV-T Model Series Features of Honeywell Integrated Controls SystemTools Required for Service Specifications Sequence of Operation Troubleshooting Verify Primary and Secondary voltage at the control boardError code #63 on display. See Main Burner short Pressing Select button will change display to next mode Max Setpoint Display/Change Setpoint Display/Change Software Version Display only SET ExitingSELECTServiceSETMode Display of Water TemperatureTo Display and Change Temperature Setpoint To Display Flame Sense Current of the Pilot Flame SensorSetpoint Flashes Idle Status Operational Select SET Error Codes and Error History Display Error Code HistoryTo view previous error codes ExitingSELECTServiceSETMode Error Code Definitions Resetting Error Codes in Hard Lockout Condition Service Procedure PDV24-I Unplug or disconnect electrical power to the water heaterService Procedure PDV24-I Upper Sensor Lower SensorService Procedure PDV23-II Service Procedure PDV24-II Service Procedure PDV24-II Service Procedure PDV24-III ConditionCondition Error code 57 Flame Rod Shorted To Ground Probe Service Procedure PDV24-IV To control boardCorrect improper venting condition Manifold Pressure Port Service Procedure PDV24-V PDV S&T ModelsPDV S&T Models PDV S&T Models Induced Draft Models Main Burner RemovalPilot Burner Removal Pilot Burner InspectionService Procedure PDV24-VI Control board replacementRemove lower sensor Service Procedure PDV24-VII Service Procedure PDV24-VIII PDV-S PDV S PDV-S PDV-T PDV T PDV-T Induced Draft Models Induced Draft Models Induced Draft Models ECO BTU/HCO2 GFI

PDV80T300, PDV100S150, PDV100T360, PDV80S150, D65T625 specifications

Bradford-White Corporation is renowned for its quality water heating solutions, with a diverse range of products designed to meet various residential and commercial needs. Among their stellar offerings are the D80T725, PDV100S200, PDV100S250, PDV80S250, and PDV802200 models, each equipped with advanced technologies and features that set them apart in the market.

The D80T725 is an innovative 80-gallon water heater that employs a powerful 75,000 BTU burner, ensuring rapid water heating for larger households. One of its key features is the Defender Safety System, which provides exceptional protection against potential hazards. The advanced electronic control system enhances efficiency and reliability, making it an ideal choice for energy-conscious consumers. Additionally, the tank's unique insulation helps maintain water temperature longer, reducing energy costs.

Moving to the PDV series, the PDV100S200 and PDV100S250 are dynamic, direct vent gas water heaters with capacities of 100 gallons and impressive BTU inputs. These models utilize a proper venting system that draws air from outside, ensuring that indoor air quality remains uncompromised. Both models feature Bradford-White's patented hydrojet total performance system, improving heat transfer by minimizing sediment buildup. This technology prolongs the lifespan of the unit while maximizing energy efficiency.

The PDV80S250, like its PDV counterparts, also utilizes direct venting technology for enhanced safety and efficiency. With an 80-gallon capacity and a robust 250,000 BTU input, this model is designed for businesses and larger households requiring significant hot water availability. The use of cutting-edge insulation technology in these models reduces standby heat loss, which translates to substantial savings on energy bills.

Lastly, the PDV802200 stands out with similar advanced features but offers a higher capacity of 80 gallons, making it a perfect solution for commercial applications. It strikes a balance between performance and reliability, ensuring consistent hot water delivery even during peak demand. The integration of robust safety features and user-friendly controls make it easy for facility managers to operate and maintain.

In summary, whether you opt for the D80T725 or one of the PDV models, you can expect a blend of performance, efficiency, and advanced technology. Bradford-White's commitment to quality and innovation ensures that each product meets the demands of modern consumers, making them a leading choice in the water heating industry.
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