American Water Heater ITCE3-52/80/119 Heating Element Ground Test, Replacing Heating Elements

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Heating Element Ground Test

OPERATION & SERVICE

Heating Element Ground Test

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

2Verify with an AC volt meter that there is not any voltage present at the Power Distribution Block (see Figures 1 and 2 on pages 8 and 9) and at the two wiring terminals on the ends of all heating elements.

3Disconnect both power wires from the terminals on the top of all heating elements to be tested.

4Using an ohm meter: set the ohm meter to one of it’s lowest resistance ranges - 200 ohms or less initially. An audible beep continuity test setting can also be used on ohm meters so equipped.

5Touch one of the ohm meter probes to one of the two heating element wiring terminals and the other probe to a grounded surface on the water heater such as the water heater’s storage tank (use sand cloth if necessary to remove any coating that may prevent metal to metal contact) or the water heater ground wire connection. Check between the other heating element terminal and ground also - see the image below.

6If there is infinite resistance - no continuity - between both heating element wiring terminals and ground the heating element(s) is not grounded.

7If there is any resistance measured - there is continuity - between either heating element wiring terminal and ground the heating element is defective and must be replaced. Ensure the voltage and KW rating of the replacement heating element is the correct rating for the water heater being serviced - see Heating Element Ratings and Heating Element Configurations on page 21.

Checking an electric heating for any resistance or continuity to ground. Touch one of the ohm meter probes to one terminal on the end of a heating element and the other probe to a grounded surface on the water heater.

Replacing Heating Elements

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

2Verify with an AC volt meter that there is not any voltage present at the Power Distribution Block (see Figures 1 and 2 on pages 8 and 9) and at the two wiring terminals on the ends of all heating elements.

3Disconnect both power wires from the terminals on the top all heating elements being replaced.

4Drain the water heater - follow the draining instructions in the Maintenance Section of Instruction Manual that came with the water heater. If the Instruction Manual is not available copies can be obtained from the manufacturers web site or by calling the toll free phone number on the back cover of this manual.

5Remove/install heating elements using a 1 1/2” six point socket. Install a new heating element gasket with the new element. Replacement elements and gaskets can be obtained from local distributors or by calling the toll free phone number on the back cover of this manual.

Servicing should only be performed by a Qualified Service Agent

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Contents Service Handbook COMMERCIAL ELECTRIC WATER HEATERSMODELS STCE3-52/80/119 & ITCE3-52/80/119 Technical Support and PartsPage SERVICE MANUAL TABLE OF CONTENTSCOMMERCIAL ELECTRIC WATER HEATER QUALIFICATIONS - QUALIFIED SERVICE AGENT SERVICE WARNINGIMPORTANT SERVICE REMINDER INTRODUCTIONINSTRUCTION MANUAL TOOLS REQUIREDCLOSED WATER SYSTEMS INSTALLATION CONSIDERATIONSTHERMAL EXPANSION ELECTRICAL REQUIREMENTS Power SupplyGrounding WIRING CONNECTIONS PRE SERVICE CHECKSSERVICE PRECAUTIONS HEATING ELEMENT CONFIGURATIONS WATER HEATER CONSTRUCTIONSURFACE MOUNT CONTROL MODELS ELECTRONIC CONTROL MODELSSURFACE MOUNT CONTROL MODELS WATER HEATER CONSTRUCTIONELECTRONIC CONTROL MODELS OPERATION & SERVICE PRINCIPLES OF ELECTRICITYVoltage AmperageOhms Law Ohms Law applied to “SINGLE PHASE” 1Ø powerCalculating Amps/Ohms/Volts/Watts SINGLE AND THREE PHASE POWER L1 L2 L3Checking Single Phase 1Ø Power Checking Three Phase 3Ø Power 1 L1 and L2 terminals of the water heater’s Power Distribution Block2 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 Three Phase to Single Phase PHASE CONVERSIONS - SURFACE MOUNT CONTROL MODELSSurface Mount Control Models Single Phase to Three Phase Electronic Control Models Three Phase to Single Phase PHASE CONVERSIONS - ELECTRONIC CONTROL MODELSElectronic Control Models Single Phase to Three Phase Ohm Meter Method FUSESVolt Meter Method SURFACE MOUNT THERMOSTATS Thermostat & ECO Test Heating Element Construction HEATING ELEMENTSWire conductor inside tube Heating Element Configurations NUMBER OF FACTORY INSTALLEDHeating Element Ratings TOTALHeating Element Amperage ELEMENTAPPROXIMATE CURRENT - AMPS 208 VACHeating Element Amperage Test Heating Element Voltage Test Heating Element Resistance & Ground Tests Measuring ResistanceHeating Element Ground Test Replacing Heating ElementsELEMENT SENSORS Element Sensor ConstructionElement Sensor Three Current Sensors Element Sensor FunctionsElement Sensor Operation CONTACTORS Contactor Construction - How They WorkContactor Configurations Power Connection TerminalsElement Numbers/Connections Wire Colors to Elements ContactorsContactor Inspection Physically Operate MechanicalContactor Coil Voltage - At Contactor Contactor Coil Voltage - At CCB 120 VAC Control Circuit Transformer Wiring X1 120 VACTRANSFORMERS H1 H2 H3 H4 H5 N/A Primary Winding Secondary WindingPrimary Winding Voltage Test 120 VAC Control Circuit Transformer TestSecondary Winding Voltage Test 24 VAC Transformer Test IMMERSION TEMPERATURE PROBE ECO High Temperature Limit SwitchTemperature Sensor Temperature Sensor Resistance Test Temperature Sensor Resistance DataChecking Temperature Sensor Resistance WATER TEMPERATURETemperature Sensor DC Voltage Test ECO Continuity TestChecking ECO Switch Continuity DC Voltage To Temperature SensorECO Voltage Test 120 VAC To ECO120 VAC From ECO Ground ConnectionELECTRONIC CONTROLS UIM User Interface Module CCB Central Control BoardCCB - CENTRAL CONTROL BOARD CCB Socket & Wiring Terminal Identification J2 Socket - 120 VAC Power SupplyJ3 Wiring Terminals - Alarm Output Relay see page J4 Wiring Terminals - Contactor CoilsJ7 Socket - Enable / Disable Circuits 1 & 2 see pages 45 J16 Socket - Not Used J17 Wiring Terminals - Not UsedJ8 Socket - Not Used J9 Socket - Not Used J10 Socket - Not Used J13 Socket - Heating Element Sensors BankCCB Enable/Disable Circuits Test Checking for 120 VAC Checking Power and Ground To The CCBChecking for Ground Service Notes - Button Pad Ribbon Cable UIM - USER INTERFACE MODULEUIM Circuit Board Back UIM Circuit Board FrontCONTROL SYSTEM FEATURES ELECTRONIC CONTROL SYSTEMCONTROL SYSTEM NAVIGATION UIM - User Interface ModuleTHE DESKTOP SCREEN Table 1 Status Icons ICONTable 2 - Operating States Table 3 - Control System MenusSTATE MENUS†Differential Settings TEMPERATURES MENUOperating Set Point Tank TemperatureTemperature Settings Enable / Disable 1 Alarm ConditionAlarm Relay Output HEATER STATUS MENUECONOMY MODE SETUP MENU Setpoint AdjustmentDesktop Screen During Economy Mode Economy Mode Setup Menu Current TimeEconomy Mode Settings Setpoint Adjustment Value Economy Mode Settings Time Clock Settings Economy Mode All Day Economy Mode Settings Daily Operating Mode SettingsNormal Operation Between ALARM OUTPUT SETUP MENU Temp Alarm SP Used for externalAlarm SP Alarm Output SettingsDISPLAY SETTINGS MENU Display SettingsTemperature Units Backlight DelayHEATER INFORMATION MENU Elapsed TimeTotal Heating Time Bank # CyclesCURRENT FAULT / ALERT MENU FAULT HISTORY MENUFAULT OCCURRENCE MENU Main Menu - Current Fault Selected Fault History MenuRestore Factory Defaults RESTORE FACTORY DEFAULTS MENUFactory Default User Settings TROUBLESHOOTING COMMON SERVICE PROBLEMSNo Hot Water Not Enough Hot WaterFault Conditions Resetting Control SystemCONTROL SYSTEM UNRESPONSIVE Alert ConditionsControl System Unresponsive cont Heating Cycle DisabledUIM is Inoperable FAULT AND ALERT MESSAGES “No Current Detected”“Temp Probe Open” Fault & Alert Messages“Temp Probe Short” “Energy Cut Out ECO” Page Page Page Page Technical Support and Parts