Bradford-White Corp BRHHV, BRHHH warranty Resolving Lockouts, Delayed Ignition Possible Causes

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ΒΡΑΔΦΟΡΔ ΩΗΙΤΕ ΧΟΡΠ.

 

 

 

 

6.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 30 second post-purge. If a pump time delay is used, the pump will continue to run for the specified amount of time (adjustable from 0.1 to 10 minutes).

8.2Resolving Lockouts

There are many causes of lockouts. The four

most common causes are: (1) inadequate gas supply,

(2)poor combustion, (3) ignitor failure (4) combustion

air.

1.Inadequate gas supply: Before proceeding, ensure that the gas supply has not been shutoff or the LP tank (LP boilers) is not empty. Then, restart the boiler and observe the operational cycle. After the pre-purge time, the unit should light. If it does not, consult the factory.

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). If an improper gas/air ratio is suspected, consult the factory.

3.Ignitor failure: If the boiler 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 (Ω) ohms. If the resistance is not 50-80 ohms (Ω), replace the ignitor. If the resistance is correct, reset the boiler and check for 120 VAC at the ignitor plug during the start cycle. If there is no voltage, replace the faulty ignitor wire harness.

4.Inadequate combustion air: If the boiler goes through a normal ignition cycle, and shuts off after the blower ramps up to full speed, an abnormal restriction in the air intake or exhaust system should be suspected. Check the air filter for buildup of debris and clean filter if necessary. Inspect all exhaust venting and intake venting for blockages. Remove any blockages and inspect and replace any damaged vent sections. If the unit still continues to lockout after igniting, consult the factory.

Once the reason for the lockout has been identified and resolved you can reset the unit by pressing the manual reset button (see Detail A in Figure 30, Control Panel).

8.3 Delayed Ignition - Possible Causes

8.3.1High Lockup Pressure (LP Appliances)

- Occurs on Start-up

High lock up pressure is the most common cause of delayed ignitions on LP fueled appliances. It may result from an improper second stage regulator selection or from a faulty regulator.

Lock up can be detected by measuring the gas supply pressure to the appliance at the inlet pressure port on the gas valve. The gas supply to the appliance must be shut off before making any connections.

To check: use a water manometer or pressure gauge with a scale reading of at least 25 in. W.C. or 15 oz/ in2. (6.2kPa). Attach the manometer to the gas valve inlet pressure port. Turn on the gas supply. The Brute Magnum appliance is designed to operate with supply pressures of 4-13 in. W.C. (2.3 - 7.5 oz/ in²) (1.0-3.2kPa). If the supply pressure exceeds 13 in. W.C. (7.5 oz/ in²) (3.2kPa) (with the appliance off) it is possible that this may be the cause of the delayed ignitions and the inlet pressure must be reset to between 4-13 in. W.C. (2.3 – 7.5 oz/in2) (0.1-3.2kPa). Restart the appliance and then switch it off. If the inlet gas pressure exceeds 13 in. W.C. (7.5 oz/ in²) (3.2kPa) after the appliance is switched off, correct the lock up problem.

8.3.2Gas Valve Regulation

Gas valve regulation problems can also cause delayed ignitions. If gas valve regulation problems are suspected, consult the factory. Do not attempt field adjustment or repair.

8.3.3Defective Burner - Occurs on Startup

or at Burner Shutdown

A defective burner can cause a delayed ignition. If the gas supply pressure is proper, and the gas valve is functioning properly, the burner should be inspected. There should be no distortion or perforations in the burner. Replace if indicated.

8.4Short Cycling — Boiler

Because the Brute Magnum 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. See Section 5.5 regarding controller setup. Contact your Representative to discuss possible remedies.

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Contents Βρυτε Μαγνυμ Βραδφορδ Ωηιτε Χορπ Table of Contents MaintenanceTroubleshooting Replacement PartsList of Tables List of FiguresGeneral Information IntroductionModel Identification Model DesignationLocating the Appliance WarrantyDimensions Inches 91cm horizontally Venting and Combustion AIR Combustion AirCombustion Air From Room Intake Combustion AirHorizontal Vent Terminal VentingLocating Vent & Combustion Air Terminals Combustion Air and Vent Through Side Wall Installation of Carbon Monoxide Detectors From Massachusetts Rules and Regulations 248 CMRCommon Vent Test Boilers Side Wall Combustion Air TerminalVertical Vent Terminal Vertical Combustion Air TerminalGAS Supply and Piping Distance from Gas Meter or Last Stage Regulator4A.2 Cold Water Make-Up Boiler Water Connections Brute Magnum Boiler4A.1 Heating System Piping Hot Supply Connections Boiler Water Connections Brute Magnum Water Heater 4A.3 Freeze Protection Boiler4B.1 Water System Piping Water Heater 4B.2 Hot Water Supply Piping Water Heater4B.3 Water Flow Requirements Water Heater Hydronic Piping Multiple BoilersHydronic Piping Multiple Boilers Alternate Hydronic Piping One Boiler, Multi-Temperature System 4B.4 Combined Water potable Heating and Space HeatingHeater or in the pipes in the system. When water 4B.5 Freeze Protection Water HeaterWater Heater Piping One Heater, One Tank Water Heater Piping Multiple Heaters, One Tank Water Heater Piping One Heater, Multiple Tanks Water Heater Piping Multiple Heaters, Multiple Tanks Main Power Temperature Control BoilerTemperature Control Water Heater Electrical ConnectionsTemperature Control Features Internal Water Heater Temperature ControlTemperature Setpoint Differential SettingOffset Throttling RangeMinimum Output Setting Integration ConstantMixing System and Control Control Parameter Possible InterferenceWiring Diagrams External Control ConnectionsWiring Diagram, Size 1200, Standard and Codes a and F Βρυτε Μαγνυμ Wiring Diagram, Size 1200, Code B Wiring Diagram, Sizes 1600, 2000 and 2400, Code B Wiring Schematic, Model 1200, Standard and Codes a and F Wiring Schematic, Model 1200, Code B Filling the Boiler System Operating the Burner and Set UpOperating Instructions Gas/Air Test Panel Maintenance System MaintenanceAppliance Maintenance Component Description Shutting Down the Brute MagnumGas Trains Modulating Gas Valve BurnerFilter Safety Gas Valve Manual Reset High Limit ControlAuto Reset Temperature Limit Mixing ControlIgnitor / Flame Sensor Assembly Flow SwitchMixing Actuator Ignition ControlTroubleshooting Motorized Safety ValveGas Pressure Switches Sequence of OperationShort Cycling Boiler Delayed Ignition Possible CausesResolving Lockouts High Gas Consumption Replacement PartsShort Cycling Water Heater Parts List Combustion Components See FigureElectrical Components See Figure Jacket See Figure Combustion Components Gas Train/Combustion Air Components Gas Train Components Electrical Components Heat Exchanger / Water Path Components Heat Exchanger / Water Path Components Jacket Components Litho in U.S.A. Bradford White 1102 Document