A.O. Smith BFC - 60, BFC - 30 service manual Appliances heating cycle Protection for the appliance

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2

Working principle of the appliance

gis

2.3The appliance's heating cycle

2.4Protection for the appliance

2.4.1

In this appliance the cold water enters the bottom of the tank via the cold water inlet (14). Once heated by the combustion chamber (8) and heat exchanger (11), the hot tapwater leaves the tank through the hot water outlet (2). Once the appliance is completely filled with water, it remains constantly under water supply pressure. As hot water is drawn from the appliance, it is immediately replenished with cold water.

The air required for combustion is forced into the burner (17) by the fan (18).

The gas is fed to the burner via the gas valve (16). Thanks to the modulated supply of gas and air, the optimum gas/air mixture is always achieved. The special construction of the burner causes the mixture to form a vortex (the cyclone effect), before it becomes ignited. This vorticity improves the ignition on the hot surface igniter (20), as well as ensuring optimum combustion efficiency. Through the special design of the heat exchanger (11), the flue gases are first led downwards via the combustion chamber, then upwards again via the heat exchanger, then once more downwards beside the water in the tank. In this process, the flue gases gradually become cooler. Because the cooled flue gases flow alongside the cold water lower down in the tank, they start to condense. This condensation causes latent heat energy to be released, which is transferred to the cooler water, thereby increasing the energy performance of the unit. The condensate yielded by this process is discharged via the siphon (23).

The insulation layer (24) prevents heat from escaping. The inside of the tank is enamelled to protect against corrosion. The anodes (9) provide extra protection against corrosion.

For use during maintenance, the appliance has an inspection and cleaning opening (12).

The water temperature is measured by temperature sensors T1 (7) in the top of the tank (10) and T2 (13) at the bottom of the tank. These temperatures are sent to the electronic controller. Based on these two observations, the electronic controller calculates a net water temperature: Tnet. The value of Tnet lies between the temperatures at the top and bottom of the tank. As soon as Tnet falls below the set water temperature (Tset), the electronic controller registers a "heat demand". The gas control (16) is opened, and the gas is mixed with air. This mixture is ignited by the hot surface igniter (20) and the water becomes heated. As soon as Tnet rises above Tset the heat demand ends, and the electronic controller stops the heating cycle.

The electronic controller assumes a certain margin both when registering and ending heat demand. We refer to this margin as the hysteresis (12.2 "Setting the hysteresis").

Introduction

The electronic controller monitors the water temperature and ensures safe combustion. This is achieved by:

•the Water temperature protection;

•theGas valve;

•the Fan;

•the Pressure switch;

•the Flame probe.

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Instruction manual BFC

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Contents Installation User Your installer Liability Read this manual carefullyTrademarks More informationGis Table of contents Maintenance frequency Service programTroubleshooting Performing maintenanceAppendices Table of contents What to do if you smell gas Regulations IntroductionAbout the appliance Introduction Target groups MaintenanceSymbol Target group Gis Chapter Target groups Description Overview of thisDocument General working principle of the appliance Safety of the installationWorking principle of the appliance Appliances heating cycleAppliances heating cycle Protection for the appliance Water temperature protection TheGas valvePressure switch Flame probe Working principle of the applianceGas valve Water temperature protectionPressure switch 4 FanVented installation Safety of the instal- lationUnvented installation Flame probeEnvironmental InstallationPackaging ConditionsWater composition Air humidity and ambient temperatureAppliance maximum floor load Working clearancesWorking clearances Dimensions of the appliance Technical specifica- tionsSion General and electrical specificationsDimen Description Unit BFCGas category 2H G20 20 mbar Gas dataDescription II2H3+ Unit General 3+Installation diagram Hot water side Water connections, UnventedCold water side Circulation pipeWater connections, Vented Requirements for flue gas discharge materials Gas connectionAir supply and flue Introduction C43 B23 C33 C13 C53 Type of appliance Description Concentric connectionsPractical example of concentric flue gas discharge Appliance Diameter Maximum length Number of 90º BendsSpecifications Appliance with concentric flue gas discharge materialConcentric wall flue terminal specifications C13 Specification DescriptionParallel connections Practical example of parallel flue gas outletPreparation Connecting the mains voltage Electrical connectionPreparation 10.2 Preparation Connecting the mains voltageIsolating transformer Connecting an extra on mode switch Tank on Connecting continuous pumpConnecting a program-controlled pump Connecting an extra error signal Alarm OUTChecking the supply pressure and burner pressure 11.1Procedure to check pressures Gas data Adjusting the pressureFinalising Finish off 3.11.4 FinalisingOrifice assembly Conversion to a different gas categoryConversion to a different gas category Conversion of gas controlPage Conversion to a different gas category Installation diagram FillingFilling the appliance Filling unvented installationsFilling vented installations FillingDraining Draining Min Gis Controls Electronic controller ON/OFF switchControl panel Meaning of iconsPC connection Control panelOperating modes Operating modes Error conditions Service conditionStatus of the appliance Status of the appliance Error conditionsManual 13 Troubleshooting Menu 11 Main menu chapterService condition Manual 14 Maintenance frequencyGis Appliances heating cycle Open 3.5 Installation diagram the manual gas valveStarting and running Starting and running Appliances heating cycleStarting and running Electrically isolating the appliance Shut the appliance down for a brief period OFF modeShutting down Shutting the appliance down for a long periodShutting down Notational convention for menu-related instructions Switching on the on modeMain menu Starting and stopping the week program Setting water temperature during on modeWeek program Changing the appliances standard week programWeek program setting the water temperature Week program setting the switch- on timeWeek program setting the switch- off time Week program setting the program- controlled pump Adding times to a week programDeleting times from a week program Extra periodSetting the water temperature Setting the switch-on timeSetting the switch-off time Setting the program-controlled pumpSetting day and time SettingsSetting menu language Adjustable settingsDisplaying appliance specifications Displaying the error history Service programSetting the hysteresis Setting the display contrast Switching the pump on or offSetting the service interval Setting the display backlight timeDisplayed errors TroubleshootingGeneral errors Display is off Troubleshooting table for general errorsSymptom Cause Solution Remark Gas smell Start the appliance up 9 Starting and runningHot water supply Symptom Cause Solution Remark Water leakageExplosive ignition Insufficient or absentTroubleshooting table for displayed errors Displayed errors S14 blocking error Code + Description Cause Solution Remark S12 blocking errorS13 blocking error S15 blocking errorCode + Description Cause Solution Remark F02 lock out error Code + Description Cause Solution Remark Check the values 2.4.5 Pressure switchAppliance Code + Description Cause Solution Remark F03 lock out errorMaintenance 15.2 Preparation for maintenance. If there is FlueCode + Description Cause Solution Remark F04 lock out error F05 lock out errorF08 lock out error Code + Description Cause Solution Remark F06 lock out errorF07 lock out error F09 lock out errorCode + Description Cause Solution Remark F10 lock out error F11 blocking errorC04 blocking error Code + Description Cause Solution Remark C02 lock out errorC03 blocking error Selected applianceE04 lock-out error Code + Description Cause Solution Remark E01 blocking errorE03 lock-out error Page Maintenance frequency IntervalMaintenance frequency Performing maintenance Introduction Preparation for maintenancePerforming maintenance Checking the anodes Descaling and cleaning the tankWater-side mainte- nance Introduction Clean the orifices Cleaning condensation water dischargeClean the burners Cleaning the heat exchanger Finalizing mainte- nance16.2 Tank warranty Warranty certificate16.1 General warranty Conditions for Instal- lation and useWarranty certificate Electrical diagram AppendicesElectrical diagram AppendicesTerminal Block Connections Appendices Tset Pump Week program cardPeriod Example PeriodPage Index 0306 Index

BFC - 30, BFC - 60 specifications

A.O. Smith is a well-regarded name in the water heating industry, known for producing innovative and efficient water heaters. Among their renowned products are the BFC - 60 and BFC - 30 models, which have gained popularity for their performance and reliability.

The A.O. Smith BFC - 60 and BFC - 30 are both designed to meet the diverse needs of residential and commercial users. The BFC - 60 has a capacity of 60 gallons, making it ideal for larger households or commercial settings where hot water demand is high. Meanwhile, the BFC - 30, with its 30-gallon capacity, caters to smaller households or establishments with lower hot water requirements.

One of the standout features of both models is their advanced heating technology. They are equipped with a high-efficiency burner system, which enhances the heating process while minimizing energy consumption. This means that users experience quicker recovery times and can enjoy a steady supply of hot water without the long wait associated with traditional heaters. The BFC series is designed to save energy, aligning with modern demands for sustainability.

Another significant characteristic of these models is their durable construction. Made with high-quality materials, including glass-lined tanks, they are built to resist corrosion and extend the lifespan of the water heater. This durability contributes to fewer maintenance requirements, giving users peace of mind.

In terms of safety, A.O. Smith has incorporated numerous features into the BFC series. Both models come with safety valves and thermostat controls to ensure that water is heated to appropriate temperatures, reducing the risk of scalding and malfunction. Additionally, their design allows for easy installation and maintenance, making them a user-friendly option.

Another aspect that distinguishes the BFC series is its compact design. Both models have a space-saving profile, making them suitable for installation in various locations, including tight utility rooms or basements. This flexibility allows homeowners and businesses to maximize their space without sacrificing performance.

Overall, the A.O. Smith BFC - 60 and BFC - 30 are exemplary water heating solutions that combine efficiency, durability, and safety. With their advanced features and technologies, they are an excellent choice for anyone in need of reliable hot water, ensuring comfort and satisfaction for years to come.
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