American Water Heater STCE3-52/80/119 Troubleshooting, Common Service Problems, No Hot Water

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TROUBLESHOOTING

TROUBLESHOOTING

TROUBLESHOOTING

COMMON SERVICE PROBLEMS

No Hot Water

1Hot water supply valve turned off.

2Check power to the water heater - see pages 12 - 14.

3Check thermostat/ECO controls on Surface Mount Control Models - see pages 18 & 19.

4Check Operating Set Point and Differential Set Points on Electronic Control Models - see pages 52 & 53.

5Check all fuses - see page 17.

6Check heating elements pages 20 - 26.

7Ensure both enable/disable circuits at the CCB’s J7 plug/socket connection are closed circuits on Electronic Control Models. See CCB Enable/Disable Circuit(s) Test on page 45.

Not Enough Hot Water

1Water heater may be undersized.

2Check thermostat/ECO controls on Surface Mount Control Models - see pages 18 & 19.

3Check Operating Set Point and Differential Set Points on Electronic Control Models - see pages 52 & 53.

4On Electronic Control Models ensure the water heater is not in the Economy Mode during peak demand periods and ensure the time is set correctly (daylight savings etc) - see pages 55 - 58.

5Ensure the power supply matches the listed voltage on the water heater rating plate - see pages 12 - 14.

6Check for water supply piping leak or restriction: lime/scale - valve partially closed.

7Check all fuses - see page 17.

8Check heating elements pages 20 - 26.

9Check Contactors on Electronic Control Models - see pages 29 - 33.

10Check both enable/disable circuits at the CCB’s J7 socket on Electronic Control Models. If either/both circuits are being used by a supervisory control(s) check that control’s settings to ensure it is not disabling heating operation during occupied/normal demand periods. See the CCB Enable/Disable Circuit(s) Test on page 45 and Heater Status Menu information on page 54.

Water Heater Trips Breaker

1Ensure the power supply breaker/fusing to the water heater meets the minimum required fuse/wire/breaker sizing. See the listed voltage and amperage on the water heater rating plate - see pages 12 - 14.

2Ensure the internal power supply phase wiring is configured correctly - see pages 15 & 16.

3Check for grounded heating elements - see page 26.

4Check for pinched/shorted wiring - internal wiring or power supply wiring.

Contactor Chatter

Condition: contactors opening and closing rapidly.

1Ensure the 120 VAC Control Circuit Transformer is properly configured to match the power supply to the water heater on Electronic Control Models - see page 34.

2Ensure the power supply to the water heater matches the listed voltage on the water heater rating plate - see pages 12 - 14.

3Ensure wiring connections at 120 VAC contactor coil(s) are secure and in good condition - see page 32.

SURFACE MOUNT CONTROL MODELS

See the Common Service Problems above.

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
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