Bradford-White Corp BWCV warranty SECTION Trouble Shooting, Resolving Lockouts, Short Cycling

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Internet Version for Reference Only

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Bradford White

 

 

 

 

10.Inspect the inside of the copper tubes for scale buildup. Scale can build up on the inner surface of the heat exchanger tubes, which can restrict water flow. If the tubes show signs of scaling, clean the internal surface. Bradford White offers a tube cleaning kit part number R0010000.

11.Reassemble in the reverse order, and check appliance operation after start-up.

NOTE: The Warranty does not cover damage caused by lack of required maintenance, lack of water flow, or improper operating practices.

SECTION 8.

Trouble Shooting

8.1 Resolving Lockouts

There are many causes of lockouts. The three most common causes are: (1) inadequate gas supply,

(2) poor combustion, (3) ignitor failure.

1.Inadequate gas supply: Before proceeding, ensure that the gas supply has not been shutoff or the LP tank (LP heaters) is not empty. Then, restart the heater and observe the operational cycle. After

a 15-second fan pre-purge, the ignitor will heat up for 20 seconds, and then the unit will light. If it does not, check the gas supply pressure to the appliance, after resetting the appliance and attempting another start-up. The gas pressure to the appliance must be above 5" W.C. (1.2kPa) throughout the entire start-up cycle. If it is not, correct the supply problem (check gas valves or supply piping). If the supply pressure is adequate, consult the factory for assistance.

2.Poor Combustion: Poor combustion should be suspected if there is a strong flue gas odor. The odor may result from an improper gas/air ratio (high or low O2 or CO2). Copper Brute II appliances operate best with 45% excess air (8% CO2 on natural gas, 9.2% CO2 on LP). Check the CO2 of the appliance and adjust if necessary.

3.Ignitor failure: If the heater goes through a normal start cycle but combustion does not occur, ignitor failure should be suspected. Check the ignitor by unplugging the ignitor plug and measuring the ignitor resistance. It should be

50-80 ohms. If the resistance is not 50-80 ohms, replace the ignitor. If the resistance is correct, reset the heater and check for 120 VAC at the ignitor plug during the start cycle. If there is no voltage, replace the faulty ignitor wire harness or the ignition control.

8.2Delayed Ignition — Possible Causes

A defective burner can cause a delayed ignition.

If the gas supply pressure is proper and the gas valves are functioning properly, then burners should

be inspected. There should be no distortion or perforations in the burners outside of the active burner port area. Replace if indicated.

8.3Short Cycling

Short cycling will generally occur only in

combination space heating and water heating applications when the water heater is operating in the space-heating mode. Because the Copper Brute II is a stage-fired water heater and its input will reduce when there is a reduction in heating load, short cycling is greatly reduced. If the heating load drops below the minimum input of the water heater for an extended period, the water heater will have a tendency to short cycle. If short cycling is frequently experienced, regardless of the control’s attempt to limit it, the heating load should be redistributed to control it. See Section 6.2 regarding controller setup.

If short cycling occurs in a water heater application, it is probably caused by undersized piping between the water heater and the storage tank or by some other factor that restricts proper water flow through the water heater. The cause should be determined and corrected.

8.4High Gas Consumption

Appliances operating with an improper air/fuel

ratio are very inefficient and consequently, have very high gas consumption. Because efficiency is high when the CO2 is high (or O2 is low), appliances operating with low CO2 or high O2 (especially LP appliances) consume more gas. Adjust the CO2 or O2 for optimum efficiency. If no combustion analyzing equipment (CO2 or O2) is available then a proper adjustment of the air/fuel ratio (CO2 or O2) cannot be accomplished. However, by briefly sniffing the flue gases it is possible to determine if the CO2 or O2 is within the proper range. No significant flue gas odor should be detected when combustion is proper. A strong piercing smell indicates poor combustion and generally a lean mixture - low CO2 or high O2 . The CO2 should be 8% at high fire. To check the CO2, first verify that the supply gas pressure is within 5" to 13" w.c. (1.2 to 3.2 kPa) With the heater running with all stages firing, set the air box pressure to 1.5" w.c. (0.37 kPa) (as a starting point), by adjusting the air shutter(s) at the bottom of the fan(s). Check the CO2, and adjust the air shutters if further adjustment to the CO2 is needed. Models 1250 to 2000 have two blowers and two air chambers (boxes). The pressure of each air box must be equal when the final adjustment is made.

8.5Troubleshooting the Temperature Control

A trouble shooting chart for the temperature control is shown on the following page.

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Contents Installation and Operation Instructions Internet Version for Reference OnlyInstallation and Operation Instructions for Copper BruteSECTION 8. Trouble Shooting TABLE OF CONTENTSSECTION 7. Maintenance SECTION 9. Wiring Diagrams1.1 Introduction SECTION General Information1.2 Model Identification 1.3 Warranty 1.4 Dimensions1.5 Locating the Appliance Figure 1. Dimensional Data From Outside Wall SECTION Venting and Combustion Air1.6 Locating Pump-Mounted Water Heater with Respect to Storage Tanks 2.1 Combustion Air2.1.2 Intake Combustion Air 2.2.2 Category I Vent 2.2 Venting2.2.1 Vent Categories 2.2.3 Common Venting SystemsFigure 3. Combustion Air and Vent Through Side Wall 2.3.1 Side Wall Vent Terminal 2.3 Locating Vent & Combustion Air TerminalsImportant Note Massachusetts Code Requirement 2.3.2 Side Wall Combustion Air Terminal2.3.3 Vertical Vent Terminal 2.4 Common Vent Test2.5 Vent Terminals for Outdoor Units 2.3.4 Vertical Combustion Air TerminalSECTION Gas Supply and Piping 3.1 Gas Supply and Piping4.2 Hot Water Supply Piping - Water Heater SECTION Water Connections Copper Brute II Water Heater4.1 Water System Piping Water Heater 4.3 Water Flow Requirements - Water HeaterTable 8. Water Flow Requirements Figure 4. Water Heater Piping - One Heater, One TankFigure 5. Water Heater Piping - Multiple Heaters, One Tank Figure 6. Water Heater Piping - One Heater, Multiple Tanks Figure 7. Water Heater Piping - Multiple Heaters, Multiple Tanks 4.4 Combined Water Heating potable and Space Heating - Water Heater 5.1 Main PowerSECTION Electrical Connections 4.5 Freeze Protection - Water Heater5.3 External Staging Control Wiring AVERTISSEMENT6.1 Sequence of Operation SECTION Operating Instructions6.2 Programming the Temperature Control 6.2.2 Choosing the Mode 6.2.1 System Piping “Primary Secondary Piping”“Parallel Piping” 6.2.3 Programming6.3.3 for more information BOIL MAX Boiler Maximum Temperature Boiler Start BOIL START The BOIL 6.2.4 Choosing the Mode for your Application Mechanical aquastat in a domestic hot water storage tank6.3 Advanced Topics Mode 5 Primary secondary piping with outdoor reset6.3.2 Staging Mode 6.3.1 Differential6.3.3 Boiler Minimum BOIL MIN 6.3.6 Pump Operation 6.3.4 Boiler Maximum BOIL MAX6.3.5 Boiler Target Temperature 6.3.7 Set point OperationOutdoor Design OUTDR DSGN - The 6.3.9 Outdoor Reset Operation6.3.10 External Heater Operation 6.3.11 Limit Controls 6.4 Operating the Burner and Set Up6.4.1 Set Up for 0 to 2500 Feet Altitude 6.3.12 Advanced Programming Mode6.5 Shutting Down the Copper Brute SECTION Maintenance7.1 System Maintenance 6.6 To Restart the Copper Brute7.2 Appliance Maintenance and Component Description 7.2.1 Burners 7.2.4 Manual Reset High Limit Control7.2.5 Automatic Reset High Limit Control 7.2.2 Filter7.2.10 Transformer 7.2.12 Flow Switch7.2.9 Ignition Sensors 7.2.11 Blowers8.2 Delayed Ignition - Possible Causes SECTION Trouble Shooting8.1 Resolving Lockouts 8.3 Short CyclingERROR DISPLAYED DESCRIPTION OF ERROR8.6 Troubleshooting Copper Brute II Controls SECTION Wiring Diagrams Figure 18. Copper Brute II 500 - 750 Ladder DiagramFigure 19. Copper Brute II 1000 Ladder Diagram Figure 20. Copper Brute II 1250 - 2000 Ladder Diagram Figure 21. Copper Brute II 500 - 1000 Wiring Schematic Figure 22. Copper Brute II 1250 - 2000 Wiring Schematic Figure 23. Field Wiring Note Positions of field wiring terminals may vary, butterminal designations are as indicated Figure 24. Field Reference OnlyWiring for Modes 1 MODEInternet Version for Reference Only25. Field Wiring for Mode Copper Brute II 1250, 1500, 1750 & 2000 4-Stage Heater
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