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E
E20 or E50 - Temperature sensors faulty. Cold resistance approximately
10kΩ @ 25° C (DHW and CH sensors)
20kΩ @ 25° C (Flue sensor)
(resistance reduces with increase in temp.)
E28 - Incorrect PCB fitted
18.0 Fault Finding
NO
Replace sensor or PCB (E28)
F
G
1.Check and correct the connection of the tube between the venturi and gas valve
2. | Gas at burner | NO | Ensure gas is on and purged |
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PCB - X3 connector is 230V AC across | YES |
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Replace gas valve | |||||||
| terminals 1 & 2 |
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1.
Ensure that the Hall Effect Sensor is in position. | YES | Check the voltage between red wire and blue | |||||
Check the connection between the PCB - X400 |
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| wire is more than 5V DC |
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connector terminals 3,6,7 and the electronic sensor |
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H
Check and correct if necessary
1.Ignition electrode and lead
2.Electrode connection
3.Spark gap and position
Burner
Sensing
Electrode
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| . | 5 |
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7 |
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YES
Replace PCB
Voltage at PCB - X2 connector is at least 100V DC across terminals 2 & 5 (Note: from multimeter connect ‘common’ to 2 & ‘volts’ to 5).
Check wiring
Viewing Window
10 ±1
Replace Hall
Effect Sensor
NO | Replace PCB |
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YES
Replace igniter
5 . 0 ±
4
Spark Ignition
Electrode
Electrode Position
58© Baxi Heating UK Ltd 2012