American Water Heater STCE3-52/80/119, ITCE3-52/80/119 manual Element Sensor Operation

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Element Sensor Operation

OPERATION & SERVICE

Element Sensor Operation

When current (amperage) flows through a wire in an electrical circuit a magnetic field is developed that radiates out from the wire. The individual current sensors detect this magnetic field. When current flows in a wire routed through the hole in one of the individual current sensors, the sensor is activated and sends a signal back to the CCB confirming the presence of current.

The current sensors require approximately 3 AC amps minimum to activate. An active signal from a current sensor only indicates current has been sensed, it DOES NOT indicate the amount or level of current is correct for a given heating element.

As explained on the previous page Element Sensors contain three individual current sensors. The three sensors are installed just above the power circuit fuse blocks. One heating element power wire is routed through a hole in one sensor.

The plug from each Element Sensor plugs into one of three sockets on the CCB. The J12, J13 and J14 sockets are for heating element Banks 1, 2 and 3 respectively. See the images below.

Service Note: The Element Sensors cannot be serviced in the field. If it is determined one of the three individual current sensors in an Element Sensor is defective the entire Element Sensor assembly must be replaced. If current through a heating element has been verified with an AC amp meter (see page 23) and the current sensor for that element does not activate and send a signal to the CCB:

Ensure the Element Sensor plug and socket connection is making good contact.

On models equipped with 2 or 3 Banks of heating elements secure power to the water heater and try switching Element Sensor plugs between the J12, J13 and J14 sockets to verify the Element Sensor is defective - a “No Current Detected” Alert message and Status Icon indication should “follow” the defective Element Sensor and report a different heating element is not drawing current when current is expected.

CCB Element Sensor Sockets

Heating Element Wire Routing

J12 Heating Element Bank 1

J13 Heating Element Bank 2

J14 Heating Element Bank 3

Servicing should only be performed by a Qualified Service Agent

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Contents MODELS STCE3-52/80/119 & ITCE3-52/80/119 Service HandbookCOMMERCIAL ELECTRIC WATER HEATERS Technical Support and PartsPage TABLE OF CONTENTS SERVICE MANUALCOMMERCIAL ELECTRIC WATER HEATER IMPORTANT SERVICE REMINDER QUALIFICATIONS - QUALIFIED SERVICE AGENTSERVICE WARNING INTRODUCTIONINSTRUCTION MANUAL TOOLS REQUIREDINSTALLATION CONSIDERATIONS CLOSED WATER SYSTEMSTHERMAL EXPANSION Power Supply ELECTRICAL REQUIREMENTSGrounding PRE SERVICE CHECKS WIRING CONNECTIONSSERVICE PRECAUTIONS SURFACE MOUNT CONTROL MODELS HEATING ELEMENT CONFIGURATIONSWATER HEATER CONSTRUCTION ELECTRONIC CONTROL MODELSSURFACE MOUNT CONTROL MODELS WATER HEATER CONSTRUCTIONELECTRONIC CONTROL MODELS Voltage OPERATION & SERVICEPRINCIPLES OF ELECTRICITY AmperageOhms Law applied to “SINGLE PHASE” 1Ø power Ohms LawCalculating Amps/Ohms/Volts/Watts SINGLE AND THREE PHASE POWER L1 L2 L3Checking Single Phase 1Ø Power 2 L2 and L3 terminals of the water heater’s Power Distribution Block Checking Three Phase 3Ø Power1 L1 and L2 terminals of the water heater’s Power Distribution Block 3 L1 and L3 terminals of the water heater’s Power Distribution BlockPHASE CONVERSIONS - SURFACE MOUNT CONTROL MODELS Surface Mount Control Models Three Phase to Single PhaseSurface Mount Control Models Single Phase to Three Phase PHASE CONVERSIONS - ELECTRONIC CONTROL MODELS Electronic Control Models Three Phase to Single PhaseElectronic Control Models Single Phase to Three Phase FUSES Ohm Meter MethodVolt Meter Method SURFACE MOUNT THERMOSTATS Thermostat & ECO Test HEATING ELEMENTS Heating Element ConstructionWire conductor inside tube Heating Element Ratings Heating Element ConfigurationsNUMBER OF FACTORY INSTALLED TOTALAPPROXIMATE CURRENT - AMPS Heating Element AmperageELEMENT 208 VACHeating Element Amperage Test Heating Element Voltage Test Heating Element Resistance & Ground Tests Measuring ResistanceHeating Element Ground Test Replacing Heating ElementsElement Sensor ELEMENT SENSORSElement Sensor Construction Three Current Sensors Element Sensor FunctionsElement Sensor Operation CONTACTORS Contactor Construction - How They WorkElement Numbers/Connections Wire Colors to Elements Contactor ConfigurationsPower Connection Terminals ContactorsContactor Inspection Physically Operate MechanicalContactor Coil Voltage - At Contactor Contactor Coil Voltage - At CCB TRANSFORMERS 120 VAC Control Circuit Transformer WiringX1 120 VAC H1 H2 H3 H4 H5 N/A Primary Winding Secondary Winding120 VAC Control Circuit Transformer Test Primary Winding Voltage TestSecondary Winding Voltage Test 24 VAC Transformer Test ECO High Temperature Limit Switch IMMERSION TEMPERATURE PROBETemperature Sensor Checking Temperature Sensor Resistance Temperature Sensor Resistance TestTemperature Sensor Resistance Data WATER TEMPERATUREChecking ECO Switch Continuity Temperature Sensor DC Voltage TestECO Continuity Test DC Voltage To Temperature Sensor120 VAC From ECO ECO Voltage Test120 VAC To ECO Ground ConnectionELECTRONIC CONTROLS UIM User Interface Module CCB Central Control BoardCCB - CENTRAL CONTROL BOARD J3 Wiring Terminals - Alarm Output Relay see page CCB Socket & Wiring Terminal IdentificationJ2 Socket - 120 VAC Power Supply J4 Wiring Terminals - Contactor CoilsJ8 Socket - Not Used J9 Socket - Not Used J10 Socket - Not Used J7 Socket - Enable / Disable Circuits 1 & 2 see pages 45J16 Socket - Not Used J17 Wiring Terminals - Not Used J13 Socket - Heating Element Sensors BankCCB Enable/Disable Circuits Test Checking Power and Ground To The CCB Checking for 120 VACChecking for Ground UIM Circuit Board Back Service Notes - Button Pad Ribbon CableUIM - USER INTERFACE MODULE UIM Circuit Board FrontCONTROL SYSTEM NAVIGATION CONTROL SYSTEM FEATURESELECTRONIC CONTROL SYSTEM UIM - User Interface ModuleTHE DESKTOP SCREEN Table 1 Status Icons ICONSTATE Table 2 - Operating StatesTable 3 - Control System Menus MENUS†Operating Set Point Differential SettingsTEMPERATURES MENU Tank TemperatureTemperature Settings Alarm Relay Output Enable / Disable 1Alarm Condition HEATER STATUS MENUDesktop Screen During Economy Mode Economy Mode Setup Menu ECONOMY MODE SETUP MENUSetpoint Adjustment Current TimeEconomy Mode Settings Setpoint Adjustment Value Economy Mode Settings Time Clock Settings Economy Mode Settings Daily Operating Mode Settings Economy Mode All DayNormal Operation Between Alarm SP ALARM OUTPUT SETUP MENUTemp Alarm SP Used for external Alarm Output SettingsTemperature Units DISPLAY SETTINGS MENUDisplay Settings Backlight DelayTotal Heating Time HEATER INFORMATION MENUElapsed Time Bank # CyclesFAULT OCCURRENCE MENU CURRENT FAULT / ALERT MENUFAULT HISTORY MENU Main Menu - Current Fault Selected Fault History MenuRESTORE FACTORY DEFAULTS MENU Restore Factory DefaultsFactory Default User Settings No Hot Water TROUBLESHOOTINGCOMMON SERVICE PROBLEMS Not Enough Hot WaterCONTROL SYSTEM UNRESPONSIVE Fault ConditionsResetting Control System Alert ConditionsHeating Cycle Disabled Control System Unresponsive contUIM is Inoperable FAULT AND ALERT MESSAGES “No Current Detected”Fault & Alert Messages “Temp Probe Open”“Temp Probe Short” “Energy Cut Out ECO” Page Page Page Page Technical Support and Parts