UPDX Series Ultra Low NOx Power Direct Vent Gas Water Heaters SERVICE MANUAL Troubleshooting Guide and Instructions for Service (To be performed ONLY by qualified service providers) Models Covered by This Manual: UPDX250T*FRN UPDX265T*FRN UPDX275T*FRN UPDX50S50FR*N UPDX65S55FR*N UPDX75S55FR*N (*) Denotes Warranty Years Manual 238-49399-00A Save this manual for future reference
Bradford White UPDX Series Ultra Low NOx Power Direct Vent Gas Water Heaters Table of Contents PageUPDX Service Procedure Page 2 2 Introduction 4 --- How to Use This Manual 5 --- Tool Required for Service 5 --- Specifications 6 --- Control Timings 8 --- Sequence of Operation 9 --- Troubleshooting 12 --- Burner Inspection, Cleaning and Replacement 16 I Pilot Testing, Cleaning and Replacement 18 II Pressure Switch Testing and Replacement 19 III Blower Testing and Replacement
UPDX Series WARNING If the information in these instructions is not followed exactly, a fire or explosion may result causing property damage, personal injury, or death. FOR YOUR SAFETY Do not store or use gasoline or other flammable, combustible, or corrosive vapors and liquids in the vicinity of this or any other appliance. WHAT TO DO IF YOU SMELL GAS Do not try to light any appliance. x Do not touch any electrical switch; do not use any phone in your building.
UPDX Series Introduction The new Bradford White UPDX2 water heaters are designed to provide reliable performance with enhanced standard features. New design features include reliable spark to pilot ignition system, enhanced diagnostics, simplified servicing, significantly quieter operation, additional vent lengths, certified FVIR technology and Ultra Low NOx emissions.
How to Use This Manual UPDX Series It is intended for this manual to be used by qualified service personnel for the primary purpose of troubleshooting and repair of the Bradford White UPDX Series water heaters. Understanding the sequence of operation section of this manual will contribute greatly to troubleshooting the water heater. The Honeywell Gas Control will display error codes in the event of abnormal operation.
UPDX Series Specifications Power supply Dedicated 115VAC, 60 Hz, 15A Gas Supply Pipe Minimum 1/2" NPT (schedule 40 black iron pipe recommended) Approved Gas Type Natural. Unit must match gas type supplied. Gas Pressure 6.0" W.C. min. for Nat gas, 11.0" W.C. min. for L.P. gas, 14.0" W.C. maximum (Nat. & L.P.
Specifications UPDX Series Venting Specifications for: 48 Gallon 65 Gallon 75 Gallon This water heater is approved for installation with the following PVC, CPVC or ABS Schedule 40 venting material. The maximum and minimum vent lengths listed in thistable are for the exhaust portion of the vent. The intake portion of the vent must be equal to or less than the length of the exhaust. 3" Diameter (7.6 cm) PVC Vent Connector Lengths Maximum 48, 65 gal.
UPDX Series Control Timings Control Timings Ignition State Page 8 8 Timing Pre-purge 15 Seconds Trial for Ignition 90 Seconds Flame Stabilization Period 3 Seconds Inter-purge 15 Seconds Flame Failure Response Time 1.5 Seconds (2 second maximum; 1 second minimum.
UPDX Series Sequence of Operation Power Up Sequence 1. Start Up. Upon power up, the control runs a safe-start check with a typical start-up delay of 1-5 seconds. 2. Flammable Vapor Check. To assure no outputs are energized if the “Flammable Vapor Sensor” is out of range, the control will test the “Flammable Vapor Sensor” for proper operating range. If the “Flammable Vapor Sensor” is within range the control resumes normal operation with no perceptible delay.
Sequence of Operation UPDX Series Normal Heating Sequence (continued) 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 shut down and the blower will post purge for 15 seconds. The gas control LED flashes a short flash once every 4 seconds (idle) status code. Pressure Switch / Blower Temperature Switch- If either switch opens the pilot valve and main valve are shut down.
UPDX Series Sequence of Operation Abnormal Operation (cont.) 3. Pressure Switch/Blower Temperature Fault: a) Pressure Switch Closed at Start of Call for Heat - The gas control waits 4 seconds then, proceeds to flash 2 times followed by a 3 second pause. The gas control waits 2 minutes and then turns on the blower for 30 seconds. The blower turns off after 30 seconds and the gas control waits for the pressure switch to open.
UPDX Series Troubleshooting Green LED Indicator Observe green LED indicator on gas control. Error flash codes are displayed with a three second pause before repeating. Check and repair the system as noted in the troubleshooting table below. (For models with serial numbers starting with K or later see chart on page 15.) LED Status Control Status Service Procedure None, control LED not on or flashing No electrical power Control power switch in “OFF” position. Supply voltage interrupted.
UPDX Series LED Status Six-one flash, three second pause Six-two flash, three second pause Troubleshooting Control Status Probable Cause 1. Unstable pilot. 2. Pilot tube blocked or restricted. Failed to light pilot. 3. Oxidation build up on pilot electrode. System auto resets. 4. Wire damage to pilot assembly or bad connection at gas valve. 1. Vent blockage or improper vent configuration. Pressure switch 2. Pressure switch tubing kinked or blocked. or blower temp 3. Faulty pressure switch.
UPDX Series Troubleshooting Green LED Indicator Observe green LED indicator on Electronic gas control. Error flash codes are displayed with a three second pause before repeating. Check and repair the system as noted in the troubleshooting table below. (The following chart is for models with serial numbers starting with K or later.) LED Status Control Status Service Procedure None, control LED not on or flashing No electrical power Control power switch in “OFF” position. Supply voltage interrupted.
UPDX Series LED Status Six-one flash, three second pause Six-two flash, three second pause Control Status Troubleshooting Probable Cause 1. Unstable pilot. 2. Pilot tube blocked or restricted. Failed to light pilot. 3. Oxidation build up on pilot electrode. System auto resets. 4. Wire damage to pilot assembly or bad connection at gas valve. 1. Vent blockage or improper vent configuration. Pressure switch 2. Pressure switch tubing kinked or blocked. or blower temp 3. Faulty pressure switch.
UPDX SERVICE PROCEDURE I Burner Operation Inspection, Cleaning and Replacement UPDX Series Main Burner Inspection, Cleaning and Replacement At periodic intervals (not more than 6 months), a visual inspection should be made of the main burner for proper operation and to insure no debris is accumulating. Main burner should light smoothly from pilot and burn with a blue flame with a minimum of yellow tips.
UPDX SERVICE PROCEDURE I Burner Operation Inspection, Cleaning and Replacement UPDX Series Burner Cleaning (Continued) Step 4. Disconnect (unscrew) feedline from the main burner door. Main Burner Door Feedline Step 5. Remove main burner orifice from feed line (3/8" wrench). Inspect and clean if necessary Main Burner Orifice Step 6. Remove pilot assembly, refer to UPDX SERVICE PROCEDURE II for cleaning and inspection. Step 7. Reassemble burner. Step 8.
UPDX SERVICE PROCEDURE II Pilot Inspection, Cleaning and Replacement UPDX Series Pilot assembly Inspection, Cleaning and Replacement Step 1. Position gas control power switch to the “OFF” position and unplug heater from wall outlet. Step 2. Turn off gas supply to water heater. Step 3. Remove outer jacket door and remove main burner per service procedure XV, steps 1 through 9 on page 38. Step 7. Remove pilot assembly from main burner (¼" nut driver). Step 8.
UPDX SERVICE PROCEDURE III Pressure Switch Testing and Replacement UPDX Series Pressure Switch Testing WARNING 115 volt potential exposure. Use caution making voltage checks to avoid personal injury. Step 1. Position gas control power switch to the “OFF” position. Step 2. Remove the three screws (Phillips screw driver) from control access cover on blower assembly and remove cover (see photos 1 and 2). Step 3. Carefully remove pressure switch from blower housing (see photo 3).
UPDX SERVICE PROCEDURE III Pressure Switch Testing and Replacement UPDX Series Pressure Switch Replacement Step 1. Position gas control power switch to the “OFF” position. Step 2. Remove the three screws (Phillips screw driver) from control access cover on blower assembly and remove cover (see photo 5 and 6). Step 3. WARNING 115 volt potential exposure. Use caution to avoid personal injury. Gas Control shown in the “OFF” Position 5 Carefully remove pressure switch from blower housing (see photo 7).
UPDX SERVICE PROCEDURE IV Blower Testing and Replacement UPDX Series Blower Testing Step 1. Step 2. WARNING 115 volt potential exposure. Use caution when making voltage checks to avoid personal injury. Gas Control shown in the “ON” Position Position gas control power switch to the “ON” position and adjust control to call for heat. 10 Remove the three screws (Phillips Screw driver) from control access cover on blower assembly and remove cover (see photos 10 and ll).
UPDX SERVICE PROCEDURE IV Blower Testing and Replacement UPDX Series Gas Control shown in the “OFF” Position Blower Removal Step 1. Position gas control power switch to the “OFF” position. Step 2. Unplug blower power cord from wall outlet. Step 3. Disconnect vent system from exhaust adapter on top of blower. Step 4. Remove exhaust adapter from blower (blade screw driver) and retain for use on new blower Step 5. Unplug cord sets from blower. Step 6. Remove vertical air intake bracket.
UPDX SERVICE PROCEDURE V Blower Temperature Switch Testing and Replacement UPDX Series Blower Temperature Switch Testing Step 1. Position gas control power switch to the “OFF” position. Step 2. Remove the three screws (Phillips screw driver) from control access cover on blower and remove cover (see photos 18 and 19). Step 3. WARNING 115 volt potential exposure. Use caution to avoid personal injury.
UPDX SERVICE PROCEDURE V Blower Temperature Switch Testing and Replacement UPDX Series Blower Temperature Switch Replacement WARNING 115 volt potential exposure. Use caution to avoid personal injury. Step 1. Position gas control power switch to the “OFF” position and unplug heater from wall outlet. Step 2. Remove the three screws (Phillips screw driver) from the control access cover on blower and remove cover (see photos 21 and 22).
UPDX SERVICE PROCEDURE VI Gas Control/Thermal Well Testing and Replacement UPDX Series Gas Control shown in the “OFF” Position Gas Control Testing This section is for models with serial Numbers starting with “K” or earlier. See page 34 for gas control input & output testing.
UPDX SERVICE PROCEDURE VI Gas Control/Thermal Well Testing and Replacement UPDX Series WARNING Stored water may be HOT when performing the following steps in this procedure. Take necessary precaution to prevent personal injury. Determine Water Temperature Inside Tank Note: It is important to understand once the resistance for the thermal well is determined from page 25, water flow through the heater should not occur. Prior to performing the steps below, turn off the cold water supply to the water heater.
UPDX SERVICE PROCEDURE VI Gas Control & Thermal Well Testing and Replacement UPDX Series Gas Control & Thermal Well Removal From Water Heater Step 1. Position gas control power switch to the “OFF” position and Unplug Heater from power supply. Step 2. Drain heater to a point below the gas control level. Step 3. Turn off gas supply to water heater and disconnect gas piping from gas control. Step 4. Disconnect wire harnesses and burner assembly from gas control. Step 5.
UPDX SERVICE PROCEDURE VI Gas Control & Thermal Well Testing and Replacement UPDX Series Gas Control Assembly to Thermal Well Step 1. Install threaded end of thermal well into tank. Be sure thermal well flange is positioned as shown in photo 27 for proper control alignment. Step 2. Route wire leads back into relief opening. (see photo 27) Step 3.
UPDX SERVICE PROCEDURE VII Brass Well (WV4460) to Polymer Well (WV4462) Gas Control Replacement UPDX Series Brass Well (WV4460) to Polymer Well (WV4462) Gas Control Replacement Step 1. Position gas control power switch to the “OFF” position and unplug heater from power supply. Step 2. Drain heater to a point below the gas control level. Step 3. Turn off gas supply to water heater and disconnect gas piping from gas control. Step 4.
UPDX SERVICE PROCEDURE VII Brass Well (WV4460) to Polymer Well (WV4462) Gas Control Replacement UPDX Series Brass Well (WV4460) to Polymer Well (WV4462) Gas Control Replacement (Continued) Step 9. Connect new flammable vapor sensor harness leads into the flammable vapor sensor. Step 10. Reattach main burner feedline and pilot tube to gas control. Step 11. Connect spark igniter wire, flammable vapor sensor wire harness, ground wire (green) and blower harness to gas control.
UPDX SERVICE PROCEDURE VIII UPDX Series Gas Control Testing and Replacement Gas Control Replacement Step 1. Rotate knob of the gas control to the “OFF” position. Step 2. Turn off gas supply to water heater. Step 3. Disconnect gas supply line from gas control. Step 4. Turn off water supply and drain water heater completely. Step 5. Remove the wire clip from the feedline. Gas Control shown in the “OFF” position Step 6.
UPDX SERVICE PROCEDURE IX Flammable Vapor Sensor Testing UPDX Series Flammable Vapor Sensor Testing Step 1. Position gas control power switch to the “OFF” position. Step 2. Disconnect flammable vapor sensor from gas control. Step 3. Using a multi-meter set to the ohms setting check resistance of flammable vapor sensor (see caution below). Resistance must be within 3,000 ohms and 48,000 ohms. If outside of this range replace flammable vapor sensor.
UPDX SERVICE PROCEDURE X Safety Circuit Voltage Trace UPDX Series WARNING 115 volt potential exposure. Use caution making voltage checks to avoid personal injury. Safety Circuit Voltage Trace NOTE: This procedure assumes a cool tank. Step 1. Remove three screws (Phillips Screw driver) from control access cover on blower and remove cover (see photos 29 and 30).
UPDX SERVICE PROCEDURE XI 115 VAC Trace UPDX Series WARNING 115 volt potential exposure. Use caution making voltage checks to avoid personal injury. 115 VAC Circuit Trace Step 1. Verify 115VAC and proper polarity at wall outlet. Step 2. With unit plugged in and gas control power switch to the “ON” position verify LED status. LED status None, Control LED not on or flashing. Gas Control shown in the “ON” position LED status Short flash, once every four seconds.
UPDX Series UPDX SERVICE PROCEDURE XII Dip Tube Inspection and Replacement Dip Tube Inspection and Replacement WARNING Water Heater components and stored water may be HOT when performing the following steps in this procedure. Take necessary precaution to prevent personal injury. Step 1. Position gas control power switch to the “OFF” position and unplug water heater from wall outlet. Step 2. Turn off cold water supply to water heater.
UPDX SERVICE PROCEDURE XIII Anode Inspection and Replacement UPDX Series Anode Inspection and Replacement WARNING Water Heater components and stored water may be HOT when performing the following steps in this procedure. Take necessary precaution to prevent personal injury. Position gas control power switch to the “OFF” position and unplug water heater from wall outlet. Step 2. Turn off cold water supply to water heater. Connect hose to drain valve of water heater and route to an open drain.
UPDX SERVICE PROCEDURE XIIV Flue Baffle Inspection and Replacement UPDX Series Flue Baffle Inspection and Replacement Gas Control shown in the “OFF” position Step 1. Position gas control power switch to the “OFF” position and unplug blower from wall outlet. Step 2. Disconnect vent system from exhaust adapter on top of blower (see photo 37). Step 3. Remove vertical air intake bracket. Disconnect intake air piping (see photo 38). Step 4. Unplug cord sets from blower (see photo 37). Step 5.
UPDX SERVICE PROCEDURE XV Inner Door/Gasket Removal, Inspection Replacement and Reinstallation UPDX Series Inner Door Removal Procedure Step 1. Position gas control power switch to the “OFF” position Step 2. Unplug the water heater from the wall outlet Step 3. Turn off the gas supply to the water heater Step 4. Remove the outer door. Step 5.
UPDX SERVICE PROCEDURE XV Inner Door/Gasket Removal, Inspection Replacement and Reinstallation UPDX Series Inner Door Gasket Replacement Procedure. WARNING If the information in these instructions is not followed exactly, a fire or explosion may result causing property damage, personal injury or death. Step 11. After inspection of inner door as noted in step 10, completely remove gasket and adhesive residue from burner and left side inner doors as needed. Step 12.
UPDX SERVICE PROCEDURE XV Inner Door/Gasket Removal, Inspection Replacement and Reinstallation Installation of Inner Door With Gasket (Continued) UPDX Series Position Fiberglass Sock Step 15. Position the fiberglass sock containing the igniter wire against burner door flange gasket. Step 16. Firmly place right side inner door flange against the burner door flange and secure with two ¼” drive screws from step 5. DO NOT OVER TIGHTEN SCREWS. Step 17.
UPDX Series Frozen intake or exhaust vent terminal If an intake or exhaust vent terminal is blocked with ice or snow due to severe conditions, the pressure switch and control will not allow the burner to operate. This will result in a three flash error code. Once the blockage is removed (through melting or other means) the controls will let the burner operate.
Glossary of Terms BTU GPM Hz KWh LED NPT Ohms PSI RPM ECO VAC W.C.
Parts List UPDX Series 1. Blower Assembly 2. Blower Temp. Switch 3. Pressure Switch 4. Blower Gasket 5. Tee and Vent Pipe Assy. 6. Vent Adapter with Term. 7. Intake Terminal 8. Vent Terminal Elbow 9. Exhaust Adapter 10. Condensate Hose Kit 11. Flue Reducer 12. Heat Trap Insert (outlet) 13. Heat Trap Insert (inlet) 14. Hot Water Outlet Anode 15. Cold Water Inlet Diptube 16. Flue Baffle 17. Blower Harness 18. T&P Relief Valve 19. ¾ NPT PLUg 20. Direct Vent Boot Escutcheon 21. Air Intake Boot 22.
