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12

12 

Service Procedure I:

Heating Element Testing

Test for Open or Burned Out Element. 

1. STOP, DANGER! Turn power “OFF” to water heater.
2. Remove access cover from lower control box. 

    Remove insulation from inside of control box. 
3. Disconnect wires from heating element. 
4. Set multi-meter to “ohms” setting. 
5. Touch probes of multi-meter to screw terminals of 

heating element (see illustration 1). 

6. Reading should be 12.8 ohms (±6%) for a 240 volt, 

4500 watt element, see table below for other 

elements. 

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A reading outside the range indicates a bad 

element and the element must be replaced. 

Ohms of electrical Resistance 

For commonly Used Elements 

Voltage Rating of Element 

Element

Wattage 

208 

240   

480

2000 

20.3-22.9 

27.1-30.5 

114.3-122.1 

3000 

13.5-15.3 

18.0-20.4 

72.2-81.4 

4000 

10.2-11.4 

13.5-15.3 

54.1-61.0 

4500 

9.0-10.2 

12.0-13.6 

48.1-54.3 

5000 

8.2-9.2 

10.8-12.2 

43.3-48.9 

6000 

6.7-7.6 

9.0-10.2 

36.1-40.7 

Test for Grounded Element. 

1. STOP, DANGER! Turn power “OFF” to water heater.
2. Remove access cover from lower control box. 

    Remove insulation from inside of control box. 

     

3. Disconnect wires from heating element. 
4. Set multi-meter to “ohms” setting. 
5. Touch one probe of multi-meter to either screw 

terminal of heating element and the other on the 

element flange (see illustration 2). There should be no 

reading on the ohm meter. Any reading indicates a 

grounded element and the element must be replaced. 

Repeat this step for the other screw terminal. 

WARNING

High voltage exposure.  Use caution when making
voltagecheckstoavoidhazardtolifeorproperty.

Содержание ElectriFLEX HD CEHD 120

Страница 1: ...8 ECO 7960 SERVICE MANUAL Troubleshooting Guide and Instructions for Service To be performed ONLY by qualified service providers Models Covered by This Manual CEHD 50 80 120 A Bradford White ElectriFL...

Страница 2: ...ing 13 Service Procedure III Fuse Testing 14 Service Procedure IV Hi Limit Switch Testing 15 Service Procedure V Thermostat Testing 16 Service Procedure VI Contactor Testing 18 Service Procedure VII T...

Страница 3: ...f diagnosis cannot be made using the methods described in this service manual Tools Required for Service Multi Meter A digital type is strongly recommended This device is used to measure electrical va...

Страница 4: ...number is coded to identify the specific electrical characteristics used for a particular unit Below is typical model number and coded definitions In the field this information is determined from the...

Страница 5: ...5 5 General Controls Layout...

Страница 6: ...temperature is sufficient to satisfy the adjustable temperature limit of control High Limit Switch Control for Contactor Models The high limit switch will interrupt control circuit voltage causing th...

Страница 7: ...ll for heat one or more contactors will energize all heating elements simultaneously The operating coils are voltage specific When contactor replacement is required be sure to order the proper operati...

Страница 8: ...50 0 28 9 43 3 18 2 16 7 25 0 14 4 11 5 13 5 64 9 37 5 56 2 32 5 48 7 20 5 18 8 28 1 16 2 13 0 15 72 1 41 6 62 5 36 1 54 1 22 7 20 9 31 2 18 0 14 4 18 86 5 50 0 75 0 43 4 64 0 27 3 25 0 37 5 21 6 17...

Страница 9: ...or Models The system has two distinct circuits 1 Power circuit shown solid line 2 Control Circuit shown dotted line 1 Line voltage is applied across terminals of fuse block or a terminal block Line vo...

Страница 10: ...ll of water prior to energizing the water heater 2 Grounded Element In most cases an element with a short circuit to ground will cause the circuit breaker in the service panel to open or shut off In s...

Страница 11: ...nt s 3 Increase thermostat setting 4 Check thermostat 5 Check contactor operation 6 Check all wire connections 7 Reduce demand 8 Replace with larger heater 9 Temper water to heater 10 Correct plumbing...

Страница 12: ...ttage 208 240 480 2000 20 3 22 9 27 1 30 5 114 3 122 1 3000 13 5 15 3 18 0 20 4 72 2 81 4 4000 10 2 11 4 13 5 15 3 54 1 61 0 4500 9 0 10 2 12 0 13 6 48 1 54 3 5000 8 2 9 2 10 8 12 2 43 3 48 9 6000 6 7...

Страница 13: ...er 6 Use caution and check voltage across top terminals where service voltage connects to water heater see illustration 3 A Rated voltage IS present power to the water heater is okay B Rated voltage N...

Страница 14: ...llow access to fuse block 3 Locate fuse block s and remove fuses 4 Set multi meter to Ohms setting 5 Check continuity across fuse see illustration 5 A Continuity IS present fuse is okay B Continuity N...

Страница 15: ...tch reset button Recheck continuity across terminals 1 2 see illustration 6 A Continuity IS present the Hi Limit Switch has previously opened indicating the water in the tank at some point did overhea...

Страница 16: ...y thermostat operation Thermostat Control Continuity Testing 1 This procedure assumes line voltage Hi Limit Switch and contactors are in working order 2 STOP DANGER Turn power off to water heater 3 Op...

Страница 17: ...eat from the thermostat There are three different operating coils used depending on voltage rating of the water heater as follows Description Color Code 208 240 Volt Coil Green 277 Volt Coil Blue 480...

Страница 18: ...esent verify control circuit operation 2 Check for rated voltage across lower terminals of contactor s see illustration 11 A Rated voltage IS present okay go to step 3 B Rated voltage NOT present repl...

Страница 19: ...mounting screws located under thermostat dial see illustration 12 9 Once thermostat is removed disconnect wire leads to the thermostat NOTE It may be necessary to identify wires for proper reconnecti...

Страница 20: ...scale from tank surface where new Hi Limit switch will be installed 2 Slide new Hi Limit switch up into thermostat bracket until it snaps into place IMPORTANT Hi Limit switch must be set completely f...

Страница 21: ...all surfaces of the element terminal block see illustration below 2 Apply new element gasket to the new element Be sure gasket is seated against element flange without rolls or gaps see illustration b...

Страница 22: ...pect anode Anode should show signs of depletion this is normal If depletion is 1 2 of the original anode diameter original diameter approximately 3 4 replacement is recommended If any of the steel cor...

Страница 23: ...23 23 Parts List Customer must specify complete model number and serial number when ordering service parts...

Страница 24: ...Fahrenheit NPT Nation pipe thread C Degrees Centigrade ASME American Society of Mechanical Engineers 1 Large Control Box 17 NPT Nipple 2 Small Control Box 18 Temperature and Pressure Relief Valve 3 Te...

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