Bradford-White Corp BNTV, BNTH warranty SECTION Modes of Operation, Hydronic Heating Demand

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SECTION 9.

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BRADFORD WHITE CORP.

 

 

 

 

SECTION 9.

Modes of Operation

The Brute Elite control allows the boiler to operate in many different modes of operation. The mode must be selected based upon the requirements of the installation. The following sections describe the basic operation of the Brute Elite in each of the different modes. Familiarize yourself with each mode and how the operation of the boiler varies, depending upon the installation and inputs the control is monitoring.

9.1 Hydronic Heating Demand

When using the Brute Elite for hydronic heating a call for heat must be supplied to the "T-T or Interlock" terminal. Once the call is supplied the control starts the boiler and system pumps and begins the ignition process. The ignition process consists of a prepurge, trial for ignition, and run period. The prepurge period starts on a call for heat once the fan RPM reaches a preset level. The trial for ignition period follows once the start-up RPM of the fan is reached. The trial for ignition period lasts 4 seconds during which the direct spark ignition system and gas valve are energized. At the end of the trial for ignition period the flame signal is compared with the preset flame threshold value. If the flame signal is higher than the flame threshold the Brute Elite enters "run". If the flame signal is below the threshold the Brute Elite returns to prepurge and starts the ignition process over. In "run" the Brute Elite monitors the flame signal, call for heat, safeties, and water temperatures and modulates as needed between 100% and 20% of rate to satisfy the call for heat.

9.2 Hydronic Heating with Outdoor Reset

Outdoor reset varies the control point setpoint based on the actual outdoor temperature. The reset function works as shown in Figure 32. When the outdoor air temperature reaches the "high outdoor temperature setpoint (HOD), the control point setting is adjusted to the low boiler temperature setpoint (LBT). When the outdoor air temperature reaches the low outdoor temperature setpoint (LOD), the control setpoint is adjusted to the CH/Outlet water setpoint temperature. HOD, LOD and LBT can be adjusted by accessing SETUP mode. CH setpoint is adjustable from the USER menu structure.

9.3Hydronic Heating with Domestic Hot Water (DHW) Priority

When using the Brute Elite for hydronic heating with domestic hot water priority a call for heat must be supplied to the "T-T or Interlock" terminal. Once the call is supplied the control starts the boiler and system pumps and begins the ignition process. The ignition process consists of a prepurge, trial for ignition, and run period. The pre-purge period starts on a call for heat

once the fan RPM reaches a preset level. The trial for ignition period follows once the start-up RPM of the fan is reached. The trial for ignition period lasts 4 seconds during which, the direct spark ignition system and gas valve are energized. At the end of the trial for ignition period the flame signal is compared with the preset flame threshold value. If the flame signal is higher than the flame threshold the Brute Elite enters "run". If the flame signal is below the threshold the Brute Elite returns to pre-purge and starts the ignition process over. In "run" the Brute Elite monitors the flame signal, call for heat, safeties, and water temperatures modulating as needed between 100% and 20% of rate to satisfy the call for heat. When a DHW demand is applied during a hydronic call for heat the priority feature forces the boiler to switch to the DHW demand for the priority time. The DHW priority demand forces the control to operate to the DHW setpoint, de-energizes the system pump and energizes the DHW pump.

9.4Hydronic Heating Using External Modulation Control

When using the Brute Elite for hydronic heating with external modulation control a call for heat must be supplied to the "T-T or Interlock" terminal. Once the call is supplied the control starts the boiler and system pumps and begins the ignition process. The ignition process consists of a prepurge, trial for ignition, and run period. The prepurge period starts on a call for heat once the fan RPM reaches a preset level. The trial for ignition period follows once the start-up RPM of the fan is reached. The trial for ignition period lasts 4 seconds during which the direct spark ignition system and gas valve are energized. At the end of the trial for ignition period the flame signal is compared with the preset flame threshold value. If the flame signal is higher than the flame threshold the Brute Elite enters "run". If the flame signal is below the threshold the Brute Elite returns to prepurge and starts the ignition process over. In "run" the Brute Elite monitors the flame signal, call for heat, safeties, and water temperatures. The boiler

Figure 32. Outdoor Reset Setpoint Temperatures.

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Contents Installation and Operation Instructions DocumentInstallation and Operation Instructions for BRUTE ELITETABLE OF CONTENTS Brute Elite Control Setup and OperationSECTION General InformationSECTION Maintenance Trouble ShootingReplacement Parts SECTION Modes of OperationSECTION General Information 1.1 Introduction1.2 Model Identification Model NomenclatureFigure 1. Location of Components, Sizes Figure 2. Location of Components, SizesFigure 3. Location of Components, Size Figure 4. Location of Components, SizeFigure 5. Location of Components, Size Figure 6. Location of Components, SizeFigure 7. Location of Components, Sizes 750 and 1.4 Warranty 1.6 Dimensions1.3 Appliance Overview 1.5 UnpackingFigure 9. Dimensional Drawing, Sizes Dimensions are nominal and are shown in inches, cmSECTION Locating the Appliance Brute Elite is for indoor installations only2.1 Locating the Appliance SECTION Venting and Combustion Air 3.1 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 3.3 Locating Vent & Combustion Air Terminals 3.2.1 Venting Requirements Unique to CanadaA. exhaust vent terminal not included E. CPVC exhaust pipe section 80-500 not incl3.3.5 Installations in the Commonwealth of Massachusetts 3.3.2 Side Wall Combustion Air Terminal5. For concentric vent, follow instructions included with vent kit 3.3.3 Vertical Vent TerminalFigure 12. Combustion Air and Vent Through Side Wall 3.4 Common Vent Test 2. Approved Carbon Monoxide Detectors3. Signage 4. Inspection4.1 Gas Supply and Piping SECTION Gas Supply and Piping3. Refer to Tables 6A, 6B, 6C and 6D to size piping SECTION Pump Requirements 5.1 Brute Elite Boiler Flow and Head Requirements see Table5.2 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.4 BNTH Suggested Piping Schematics 6A.3 Freeze Protection6A.5 Recognized Chemicals 1. Sentinel Performance Solutions Group 2. Hercules Chemical CompanyFigure 15. Hydronic Piping - Single Boiler zoning with circulators Brute Elite Figure 17. Hydronic Piping - Multiple Boilers zoning with circulators Brute Elite PagePage Brute Elite PagePage SECTION 6B 6B.1 BNTV Water Quality6B.2 Piping Requirements Water Connections - BNTV Water Heater6B.5 BNTV Suggested Piping Schematics 6B.3 Cold Water Make-Up6B.4 Freeze Protection 6B.6 BNTV Suggested PumpsFigure 25. DHW Piping, Two Heaters, One Vertical Tank Figure 26. DHW Piping, Two Heaters, Two Vertical TanksCaution Pump sizing must be based opon water hardness at job site7.1 Main Power SECTION Electrical Connections7.10 Lead Lag/ Cascading Wiring Connections 7.2 Pump Connections7.3 24Vac Transformer with Integral Circuit Breaker 7.4 Hydronic Call for HeatFigure 28. Lead-Lag / Cascading Wiring Connections 7.11 Wiring Diagrams see Figures 29 and Figure 29. Ladder DiagramFigure 30. Wiring Diagram all sizes 8.1 Display Navigation SECTION Brute Elite Control Setup and Operation8.2 Ignition Control- Sequence of Events 8.3 Modulation Control 8.5 Anti-Short Cycle ASC8.5 High Limit 8.7 Outlet Water Temperature8.12.5 Lead Lag Base Load Setting 8.13 Boiler Pump Interrupt8.12.1 Lead Lag Setpoint 8.12.2 Lead Lag Master/Slave Selection9.2 Hydronic Heating with Outdoor Reset 9.4 Hydronic Heating Using External Modulation ControlSECTION Modes of Operation 9.1 Hydronic Heating Demand9.5 Hydronic Heating Using Local Lead- Lag/Cascading Feature 9.7 Warm Weather Shutdown9.8 Domestic Hot Water Demand BNTV only Let’s consider the following example9.9 Domestic Hot Water Heating Using External Modulation Control 10.2 Operating the Burner and Set Up SECTION Operating Instructions10.1 Filling the Boiler System 10.2.1 Burner Operation10.2.2 Boiler Setup and Adjustment 10.3 Shutting Down Brute Elite10.4 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 SECTION Maintenance 11.1 System 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 SECTION Trouble Shooting 12.3 Error Codes - See Table11.2.9 Gas Pressure Switches optional 12.1 Sequence of OperationPROBLEM SOLUTIONcontinued next page CODE#Table 18. Error Codes see SectionSECTION Replacement Parts 13.2 Parts List13.1 General Information Jacket Components - See FigureGas Train Components - See Figure Heat Exchanger Components - See Figure Contact Customer Service at 800 900-9275 Electrical Components - See FigureFigure 35. Jacket Components Figure 36A. Internal Components, Sizes Figure 36B. 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 Brute Elite Tech. Service 800 Service Parts 800Warranty Service 800 Ambler, PA
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