18.0 Fault Finding

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 PCBfitted

NO

Replace sensor or PCB(E28)

F 1.

Check and correct the connection of the tube between the venturi and gas valve

G

2.

Gas at burner

NO

Ensure gas is on and purged

 

PCB - X3 connector is 230V AC across

YES

 

Replace gas valve

 

terminals 1 & 2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

NO

 

 

 

 

 

 

 

 

 

 

 

 

Replace PCB

 

 

 

 

 

 

 

 

 

 

 

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

 

 

 

wire is more than 5V DC

 

 

connector terminals 3,6,7 and the electronic sensor

 

 

 

 

 

 

 

 

 

 

NO

 

YES

 

 

 

 

 

 

 

 

 

 

 

 

 

H

Check and correct if necessary

1.Ignition electrode and lead

2.Electrode connection

3.Spark gap and position

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

NO

YES

Replace Hall Effect Sensor

Replace PCB

Replace igniter

Burner

Viewing Window

7.5 ± 1

4 ± 0.5

10 ± 1

Electrode Position

56© Baxi Heating UK Ltd 2008

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Image 56
Baxi Potterton Gold HE A Range manual Gas at burner, Replace gas valve, Terminals 1