American Water Heater COMMERCIAL ELECTRIC WATER HEATERS, STCE3-52/80/119 manual Element Sensors

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ELEMENT SENSORS

OPERATION & SERVICE

ELEMENT SENSORS

Electronic Control Models covered in this manual monitor all heating elements using Element Sensors. Each Element Sensor monitors 3 heating elements. There will be one Element Sensor for each Bank of heating elements. See Figure 2 on page 9 and the illustration on page 30. Water heaters equipped with 3 heating elements will have 1 Element Sensor, water heaters equipped with 6 elements will have 2 Element Sensors and water heaters equipped with 9 elements will have 3 Element Sensors.

Element Sensor Construction

Element Sensors consists of 3 individual current sensors, a 10 conductor plug and 9 wires that connect between the individual current sensors and the plug. Each current sensor monitors one heating element. Current sensors are enclosed in a black plastic housing that has a hole in the middle. One power wire to each heating element is routed through the hole in one of the current sensors. See the images below.

Element Sensor

10 Conductor Plug

Three Current

Sensors

Element Sensor Functions

Working with the Element Sensors the electronic control system provides valuable operational and diagnostic information to aid in servicing:

The electronic control system displays animated Status Icons on the UIM to indicate which heating elements are being energized and which heating elements are not being energized. The Status Icons are also capable of indicating when a heating element that should be energized is not drawing current/amps. See the Status Icons Table on page 50.

The electronic control system displays a “No Current Detected” Alert message on the UIM (see pages 47 - 49) if the control system does not sense current (amperage) from a heating element when expected. IE: a call for heat is active, all contactor coils have been energized and the control system is not sensing current from one or more heating elements.

During Alert conditions the control system allows the water heater to continue heating (other elements may still be working) but prompts the user to have the water heater serviced.

Servicing should only be performed by a Qualified Service Agent

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Contents COMMERCIAL ELECTRIC WATER HEATERS Service HandbookMODELS STCE3-52/80/119 & ITCE3-52/80/119 Technical Support and PartsPage COMMERCIAL ELECTRIC WATER HEATER TABLE OF CONTENTSSERVICE MANUAL SERVICE WARNING QUALIFICATIONS - QUALIFIED SERVICE AGENTIMPORTANT SERVICE REMINDER INTRODUCTIONTOOLS REQUIRED INSTRUCTION MANUALTHERMAL EXPANSION INSTALLATION CONSIDERATIONSCLOSED WATER SYSTEMS Grounding Power SupplyELECTRICAL REQUIREMENTS SERVICE PRECAUTIONS PRE SERVICE CHECKSWIRING CONNECTIONS WATER HEATER CONSTRUCTION HEATING ELEMENT CONFIGURATIONSSURFACE MOUNT CONTROL MODELS ELECTRONIC CONTROL MODELSWATER HEATER CONSTRUCTION SURFACE MOUNT CONTROL MODELSWATER HEATER CONSTRUCTION PRINCIPLES OF ELECTRICITY OPERATION & SERVICEVoltage AmperageCalculating Amps/Ohms/Volts/Watts Ohms Law applied to “SINGLE PHASE” 1Ø powerOhms Law L1 L2 L3 SINGLE AND THREE PHASE POWERChecking Single Phase 1Ø Power 1 L1 and L2 terminals of the water heater’s Power Distribution Block Checking Three Phase 3Ø Power2 L2 and L3 terminals of the water heater’s Power Distribution Block 3 L1 and L3 terminals of the water heater’s Power Distribution BlockSurface Mount Control Models Single Phase to Three Phase PHASE CONVERSIONS - SURFACE MOUNT CONTROL MODELSSurface Mount Control Models Three Phase to Single Phase Electronic Control Models Single Phase to Three Phase PHASE CONVERSIONS - ELECTRONIC CONTROL MODELSElectronic Control Models Three Phase to Single Phase Volt Meter Method FUSESOhm Meter Method SURFACE MOUNT THERMOSTATS Thermostat & ECO Test Wire conductor inside tube HEATING ELEMENTSHeating Element Construction NUMBER OF FACTORY INSTALLED Heating Element ConfigurationsHeating Element Ratings TOTALELEMENT Heating Element AmperageAPPROXIMATE CURRENT - AMPS 208 VACHeating Element Amperage Test Heating Element Voltage Test Measuring Resistance Heating Element Resistance & Ground TestsReplacing Heating Elements Heating Element Ground TestElement Sensor Construction ELEMENT SENSORSElement Sensor Three Current Sensors Element Sensor FunctionsElement Sensor Operation Contactor Construction - How They Work CONTACTORSPower Connection Terminals Contactor ConfigurationsElement Numbers/Connections Wire Colors to Elements ContactorsPhysically Operate Mechanical Contactor InspectionContactor Coil Voltage - At Contactor Contactor Coil Voltage - At CCB X1 120 VAC 120 VAC Control Circuit Transformer WiringTRANSFORMERS H1 H2 H3 H4 H5 N/A Primary Winding Secondary WindingSecondary Winding Voltage Test 120 VAC Control Circuit Transformer TestPrimary Winding Voltage Test 24 VAC Transformer Test Temperature Sensor ECO High Temperature Limit SwitchIMMERSION TEMPERATURE PROBE Temperature Sensor Resistance Data Temperature Sensor Resistance TestChecking Temperature Sensor Resistance WATER TEMPERATUREECO Continuity Test Temperature Sensor DC Voltage TestChecking ECO Switch Continuity DC Voltage To Temperature Sensor120 VAC To ECO ECO Voltage Test120 VAC From ECO Ground ConnectionUIM User Interface Module CCB Central Control Board ELECTRONIC CONTROLSCCB - CENTRAL CONTROL BOARD J2 Socket - 120 VAC Power Supply CCB Socket & Wiring Terminal IdentificationJ3 Wiring Terminals - Alarm Output Relay see page J4 Wiring Terminals - Contactor CoilsJ16 Socket - Not Used J17 Wiring Terminals - Not Used J7 Socket - Enable / Disable Circuits 1 & 2 see pages 45J8 Socket - Not Used J9 Socket - Not Used J10 Socket - Not Used J13 Socket - Heating Element Sensors BankCCB Enable/Disable Circuits Test Checking for Ground Checking Power and Ground To The CCBChecking for 120 VAC UIM - USER INTERFACE MODULE Service Notes - Button Pad Ribbon CableUIM Circuit Board Back UIM Circuit Board FrontELECTRONIC CONTROL SYSTEM CONTROL SYSTEM FEATURESCONTROL SYSTEM NAVIGATION UIM - User Interface ModuleTHE DESKTOP SCREEN ICON Table 1 Status IconsTable 3 - Control System Menus Table 2 - Operating StatesSTATE MENUS†TEMPERATURES MENU Differential SettingsOperating Set Point Tank TemperatureTemperature Settings Alarm Condition Enable / Disable 1Alarm Relay Output HEATER STATUS MENUSetpoint Adjustment ECONOMY MODE SETUP MENUDesktop Screen During Economy Mode Economy Mode Setup Menu Current TimeEconomy Mode Settings Setpoint Adjustment Value Economy Mode Settings Time Clock Settings Normal Operation Between Economy Mode Settings Daily Operating Mode SettingsEconomy Mode All Day Temp Alarm SP Used for external ALARM OUTPUT SETUP MENUAlarm SP Alarm Output SettingsDisplay Settings DISPLAY SETTINGS MENUTemperature Units Backlight DelayElapsed Time HEATER INFORMATION MENUTotal Heating Time Bank # CyclesFAULT HISTORY MENU CURRENT FAULT / ALERT MENUFAULT OCCURRENCE MENU Main Menu - Current Fault Selected Fault History MenuFactory Default User Settings RESTORE FACTORY DEFAULTS MENURestore Factory Defaults COMMON SERVICE PROBLEMS TROUBLESHOOTINGNo Hot Water Not Enough Hot WaterResetting Control System Fault ConditionsCONTROL SYSTEM UNRESPONSIVE Alert ConditionsUIM is Inoperable Heating Cycle DisabledControl System Unresponsive cont “No Current Detected” FAULT AND ALERT MESSAGES“Temp Probe Short” Fault & Alert Messages“Temp Probe Open” “Energy Cut Out ECO” Page Page Page Page Technical Support and Parts