American Water Heater STCE3-52/80/119, ITCE3-52/80/119 Thermostat & ECO Test, Operation & Service

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Thermostat & ECO Test

OPERATION & SERVICE

Thermostat & ECO Test

1Secure power to the water heater at the main breaker or disconnect switch.

2Ensure tank temperature is less than 100°F/38°C - dump water to lower tank temperature if necessary.

3Press the red reset button firmly on all thermostat/ECO controls.

4Raise the temperature setting on all thermostat/ECO controls to 140°F or higher.

5Restore power to the water heater.

6With an AC volt meter check for voltage between the L1 and L3 terminals on the control - see illustrations below. Measured voltage should match the power supply to the water heater.

Service Note: If the measured voltage is zero volts or not the correct voltage ensure heating element power circuit wiring is correct (see wiring diagram on water heater) check fuses (page 17) and/or restore power to the water heater - see pages 12 - 14.

7With an AC volt meter check for voltage between the L4 and T2 terminals on the control - see illustrations below - if the measured voltage matches the power supply to the water heater the ECO is resetting properly. If the measured voltage between L4 and T2 is low or not present the control is defective - replace the control.

Service Note: Grounded heating elements, defective thermostats and/or a defective ECOs can all cause frequent ECO activation. If an ECO is being frequently reset on any of the thermostat/ECO controls check all heating elements to ensure they are not grounded (see page 26) first. Replace any grounded elements. If no elements are grounded replace the thermostat/ECO control(s) that require frequent resetting.

STEP 6 CHECKING POWER TO THE CONTROL

STEP 7 CHECKING POWER TO THE HEATING ELEMENT

L1

L3

L1

L3

L4

L4Manual background

T2

T2

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 TABLE OF CONTENTS SERVICE MANUALCOMMERCIAL ELECTRIC WATER HEATER SERVICE WARNING QUALIFICATIONS - QUALIFIED SERVICE AGENTIMPORTANT SERVICE REMINDER INTRODUCTIONTOOLS REQUIRED INSTRUCTION MANUALINSTALLATION CONSIDERATIONS CLOSED WATER SYSTEMSTHERMAL EXPANSION Power Supply ELECTRICAL REQUIREMENTSGrounding PRE SERVICE CHECKS WIRING CONNECTIONSSERVICE PRECAUTIONS 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 AmperageOhms Law applied to “SINGLE PHASE” 1Ø power Ohms LawCalculating Amps/Ohms/Volts/Watts 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 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 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 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 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 Power and Ground To The CCB Checking for 120 VACChecking for Ground 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 Economy Mode Settings Daily Operating Mode Settings Economy Mode All DayNormal Operation Between 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 MenuRESTORE FACTORY DEFAULTS MENU Restore Factory DefaultsFactory Default User Settings COMMON SERVICE PROBLEMS TROUBLESHOOTINGNo Hot Water Not Enough Hot WaterResetting Control System Fault ConditionsCONTROL SYSTEM UNRESPONSIVE Alert ConditionsHeating Cycle Disabled Control System Unresponsive contUIM is Inoperable “No Current Detected” FAULT AND ALERT MESSAGESFault & Alert Messages “Temp Probe Open”“Temp Probe Short” “Energy Cut Out ECO” Page Page Page Page Technical Support and Parts