Bradford-White Corp BNTV, BNTH SECTION Trouble Shooting, Sequence of Operation, Short Cycling

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11.2.9Gas Pressure Switches (optional)

Brute Elite

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11.2.9Gas Pressure Switches (optional)

The high and low gas pressure switches are 24V

manual reset switches that act to cut power to the gas valves if the gas pressure is too low or too high for proper operation. The gas pressure switches used are integrally vent limited, and do not require venting to atmosphere. To remove a switch, remove the screw on the plastic housing and pull the clear cover off. Disconnect the two wires from the screw terminals. Twist the switch off the pipe nipple. Reassemble in reverse order. For natural gas, set the low gas pressure switch to 3" w.c. For propane, set the low gas pressure switch to 5" w.c. For natural and propane, set the high gas pressure switch to 14".

11.2.10 Gas Conversion

Brute Elite units can be converted from natural to propane gas or from propane to natural gas easily in the field. Some units require the addition of a gas orifice along with proper gas valve adjustment. Other units require no additional parts, only proper gas valve adjustment. Please contact the Bradford White factory for specific information regarding the gas conversion of an appliance. If a gas conversion is performed, the unit must be identified with the appropriate gas labels and a conversion sticker to allow technicians performing maintenance in the future to properly identify the gas type of the appliance.

SIZE (MBTU)

KIT NUMBER

80

CA006201

 

 

105

CA006202

150

CA006203

199

CA006204

 

 

210

CA006204

285

CA006205

399

CA006207

 

 

500

CA006207

600

CA006207

750

CA006207

 

 

850

CA006207

Table 17. Propane Gas Conversion Kits.

SECTION 12.

Trouble Shooting

12.1 Sequence of Operation

Brute Elite is a cold start appliance that should start only on a call for heat from a tank aquastat, room thermostat, zone valve end switch or other space temperature control device.

1.Upon a call for heat: (a) the internal pump and system pump will start; (b) the blower will begin a 30 second pre-purge.

2.Following the prepurge cycle the direct spark ignition will spark and will begin a 4 second trial for ignition. The unit is allowed one or three ignition retries.

3.The gas valve will then be energized and a reduced rate ignition will occur. The unit will remain in a reduced rate start-up period for several seconds.

4.After the reduced rate start time is over, the unit will be in normal operation. Firing rate will modulate based on the heating load via the temperature controller settings and readings.

5.When the call for heat is complete, or the unit reaches its setpoint temperature, the gas valve will close, and the fan will continue to run for its 20 second post- purge. If a pump delay time is used, the pump will continue to run for the specified amount of time (adjustable from 0.1 to 10 minutes).

12.2 Short Cycling

Because Brute Elite is a modulating boiler, and its input will decrease when there is a reduction in heating load, short cycling is greatly reduced. If the heating load drops below the minimum input of the boiler for an extended period, the boiler will have a tendency to short cycle. This can be a symptom of improper control strategy or setpoints, or a load distribution problem. Brute Elite has a built-in anti-short cycle (ASC) feature. ASC is a timed setting that will delay the boiler start for a specified time after one call for heat is completed. ASC time may be adjusted as desired (see Section 8 for more information).

12.3 Error Codes - See Table 18.

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Contents Document Installation and Operation InstructionsInstallation and Operation Instructions for BRUTE ELITEBrute Elite Control Setup and Operation TABLE OF CONTENTSSECTION General InformationTrouble Shooting SECTION MaintenanceReplacement Parts SECTION Modes of Operation1.1 Introduction SECTION General Information1.2 Model Identification Model NomenclatureFigure 2. Location of Components, Sizes Figure 1. Location of Components, SizesFigure 4. Location of Components, Size Figure 3. Location of Components, SizeFigure 6. Location of Components, Size Figure 5. Location of Components, SizeFigure 7. Location of Components, Sizes 750 and 1.6 Dimensions 1.4 Warranty1.3 Appliance Overview 1.5 UnpackingDimensions are nominal and are shown in inches, cm Figure 9. Dimensional Drawing, SizesSECTION Locating the Appliance Brute Elite is for indoor installations only2.1 Locating the Appliance 3.1 Combustion Air SECTION Venting and Combustion Air3.1.1 Combustion Air From Room 3.1.2 Ducted Combustion AirFigure 10. Combustion Air and Vent Through Roof 3.2 VentingTable 5. Required Exhaust Vent Material 3.2.1 Venting Requirements Unique to Canada 3.3 Locating Vent & Combustion Air TerminalsA. exhaust vent terminal not included E. CPVC exhaust pipe section 80-500 not incl3.3.2 Side Wall Combustion Air Terminal 3.3.5 Installations in the Commonwealth of Massachusetts5. For concentric vent, follow instructions included with vent kit 3.3.3 Vertical Vent TerminalFigure 12. Combustion Air and Vent Through Side Wall 2. Approved Carbon Monoxide Detectors 3.4 Common Vent Test3. Signage 4. Inspection4.1 Gas Supply and Piping SECTION Gas Supply and Piping3. Refer to Tables 6A, 6B, 6C and 6D to size piping 5.1 Brute Elite Boiler Flow and Head Requirements see Table SECTION Pump Requirements5.2 Brute Elite Water Heater Flow and Head Requirements see Table Table 6A6A.1 BNTH System Piping Hot Supply Connections SECTION 6A Water Connections - BNTH Boiler6A.2 BNTH Cold Water Make-Up 6A.3 Freeze Protection 6A.4 BNTH Suggested Piping Schematics6A.5 Recognized Chemicals 1. Sentinel Performance Solutions Group 2. Hercules Chemical CompanyFigure 15. Hydronic Piping - Single Boiler zoning with circulators Page Figure 17. Hydronic Piping - Multiple Boilers zoning with circulators Page Brute ElitePage Page Brute ElitePage 6B.1 BNTV Water Quality SECTION 6B6B.2 Piping Requirements Water Connections - BNTV Water Heater6B.3 Cold Water Make-Up 6B.5 BNTV Suggested Piping Schematics6B.4 Freeze Protection 6B.6 BNTV Suggested PumpsFigure 26. DHW Piping, Two Heaters, Two Vertical Tanks Figure 25. DHW Piping, Two Heaters, One Vertical TankCaution Pump sizing must be based opon water hardness at job siteSECTION Electrical Connections 7.1 Main Power7.2 Pump Connections 7.10 Lead Lag/ Cascading Wiring Connections7.3 24Vac Transformer with Integral Circuit Breaker 7.4 Hydronic Call for HeatFigure 28. Lead-Lag / Cascading Wiring Connections Figure 29. Ladder Diagram 7.11 Wiring Diagrams see Figures 29 andFigure 30. Wiring Diagram all sizes 8.1 Display Navigation SECTION Brute Elite Control Setup and Operation8.2 Ignition Control- Sequence of Events 8.5 Anti-Short Cycle ASC 8.3 Modulation Control8.5 High Limit 8.7 Outlet Water Temperature8.13 Boiler Pump Interrupt 8.12.5 Lead Lag Base Load Setting8.12.1 Lead Lag Setpoint 8.12.2 Lead Lag Master/Slave Selection9.4 Hydronic Heating Using External Modulation Control 9.2 Hydronic Heating with Outdoor ResetSECTION Modes of Operation 9.1 Hydronic Heating Demand9.7 Warm Weather Shutdown 9.5 Hydronic Heating Using Local Lead- Lag/Cascading Feature9.8 Domestic Hot Water Demand BNTV only Let’s consider the following example9.9 Domestic Hot Water Heating Using External Modulation Control SECTION Operating Instructions 10.2 Operating the Burner and Set Up10.1 Filling the Boiler System 10.2.1 Burner Operation10.3 Shutting Down Brute Elite 10.2.2 Boiler Setup and Adjustment10.4 To Restart Brute Elite 3. WAIT FIVE 5 MINUTESFigure 33A. Brute Elite Gas Valves 285, 399 and 80-285Figure 33B. Brute Elite Gas Valves 600, 750 and 11.1 System Maintenance SECTION Maintenance11.2 Appliance Maintenance and Component Description yearly, unless otherwise noted11.2.5 Flame Sensor 11.2.4 Ignitor AssemblyIgniters and sensors get hot and can cause burns or injury 11.2.7 Blower 11.2.6 Transformer with Integral Circuit Breaker11.2.8 Heat Exchanger Coils 12.3 Error Codes - See Table SECTION Trouble Shooting11.2.9 Gas Pressure Switches optional 12.1 Sequence of OperationSOLUTION PROBLEMcontinued next page CODE#see Section Table 18. Error Codes13.2 Parts List SECTION Replacement Parts13.1 General Information Jacket Components - See FigureGas Train Components - See Figure Heat Exchanger Components - See Figure Electrical Components - See Figure Contact Customer Service at 800 900-9275Figure 35. Jacket Components Figure 36B. Internal Components, Sizes Figure 36A. Internal Components, SizesFigure 36C. Internal Components, Sizes Figure 37A. Gas Train Components, Sizes Figure 37B. Gas Train Components, Sizes Figure 38. Heat Exchanger Components Figure 39. Electrical Components Page Service Parts 800 Tech. Service 800Warranty Service 800 Ambler, PA
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