American Water Heater STCE3-52/80/119 Checking Power and Ground To The CCB, Checking for 120 VAC

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Checking Power and Ground To The CCB

ELECTRONIC CONTROLS

Checking Power and Ground To The CCB

The CCB circuit board is powered by the120 VAC Control Circuit Transformer (see pages 34-35)at the J2 Socket, pins 1 & 3 (see page 42). This procedure is performed to ensure the 120 VAC power is being supplied to the CCB.

1Ensure the main breaker or disconnect switch is turned on.

2Verify with an AC volt meter that proper voltage is present at the Power Distribution Block (see Figure 2 on page 9 and pages 12-14).

3Using an AC volt meter; set the volt meter to an AC voltage range just above 120 VAC.

4Ensure 120 VAC power is supplied to the CCB. With the J2 plug installed in the J2 socket on the CCB (page 42) insert the two volt meter probes into pins 1 & 3 of J2 plug as shown in the “Checking for 120 VAC” image below. Volt meter probes may have to be pressed firmly into plug to make contact with the metal conductors inside. Voltage should be approximately 120 VAC.

5If the measured voltage is approximately 120 VAC the CCB circuit board is receiving the correct power.

6If the measured voltage is zero volts or considerably less than 120 VAC:

•Check the 120 VAC wiring between the CCB J2 socket and the 120 VAC Control Circuit Transformer - ensure wiring is correct and connections are tight and making good contact.

•Check the J2 plug/socket connections on the CCB for wear or damage. Ensure they are mating properly and providing good contact - see page 42.

•Check the 120 VAC Control Circuit Transformer to ensure it is wired correctly and outputting the correct voltage - see pages 34-35.

•Check the Control Circuit fuses - see Figure 2 on page 9 for location and the Fuse test procedure on page 17.

7Ensure earth ground is supplied to the CCB. With the J2 plug installed in the J2 socket on the CCB (page 42) insert the two volt meter probes into pins 1 & 2 of the J2 plug as shown in the “Checking for Ground” image below. Volt meter probes may have to be pressed firmly into plug to make contact with the metal conductors inside. If the measured voltage is approximately 120 VAC the CCB is properly grounded.

8If the measured voltage is zero volts or considerably less than 120 VAC:

•Check the ground wiring between the CCB J2 socket and the water heater’s ground connection - ensure wiring is correct and connections are tight and making good contact.

•Ensure the water heater is properly grounded.

 

Checking for 120 VAC

 

Checking for Ground

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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 TABLE OF CONTENTS SERVICE MANUALCOMMERCIAL ELECTRIC WATER HEATER QUALIFICATIONS - QUALIFIED SERVICE AGENT SERVICE WARNINGIMPORTANT SERVICE REMINDER INTRODUCTIONINSTRUCTION MANUAL TOOLS REQUIREDINSTALLATION CONSIDERATIONS CLOSED WATER SYSTEMSTHERMAL EXPANSION Power Supply ELECTRICAL REQUIREMENTSGrounding PRE SERVICE CHECKS WIRING CONNECTIONSSERVICE 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 applied to “SINGLE PHASE” 1Ø power Ohms LawCalculating 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 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 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 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 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 Power and Ground To The CCB Checking for 120 VACChecking 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 Settings Daily Operating Mode Settings Economy Mode All DayNormal 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 MENU Restore Factory DefaultsFactory Default User Settings TROUBLESHOOTING COMMON SERVICE PROBLEMSNo Hot Water Not Enough Hot WaterFault Conditions Resetting Control SystemCONTROL SYSTEM UNRESPONSIVE 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
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