E9 and button reset and fault indicator LED are flashing. Safety temperature circuit has tripped.

StepCheck Action
1.Type of CH system:
Is the appliance installed in a fully pumped sealed system?
yes:go to step 3
no:go to step 2
2.Open vented CH system:
Is there enough water in the feed and expansion tank?
yes:go to step 4
no:▶ Top up system.
▶ Vent appliance.
▶ Press the reset button for 3 seconds and release it. After releasing the
appliance re-starts. E9? go to step 4
3.Fully pumped sealed systems:
Is the heating pressure between 1 and 2 bar?
yes:go to step 4
no:▶ Top up system.
▶ Vent appliance.
▶ Press the reset button for 3 seconds and release it. After releasing the
appliance re-starts. E9? go to step 4
4.Is the pump seized?yes:▶ Free/release the pump. If pump won’t start:
▶ Switch OFF the appliance.
▶ Disconnect the boiler power connection.
▶ Drain appliance.
▶ Change the pump (see Installation Instructions).
▶ Fill system, vent and re-pressurise (see installation instructions).
▶ Reconnect the appliance power connection.
▶ Switch ON the appliance.
▶ Press the reset button for 3 seconds and release it. After releasing the
appliance re-starts. E9? go to step 5
no:go to step 5
5.Lead disconnected from flue safety temperature limiter and/or CH flow safety temperature limiter?yes:▶ Switch OFF the appliance.
▶ Reconnect lead.
▶ Switch ON the appliance.
▶ Press the reset button for 3 seconds and release it. After releasing the
appliance re-starts. E9? go to step 4
no:go to step 4
6.▶ Switch OFF the appliance.
▶ Un-plug the connector from the flue safety
temperature limiter.
▶ Measure the flue safety temperature limiter
for continuity. Resistance small?
yes:▶ Connect flue gas safety temperature limiter lead. go to step 5
no:▶ Change the flue safety temperature limiter.
▶ Connect flue gas safety temperature limiter lead.
▶ Switch ON the appliance.
▶ Press the reset button for 3 seconds and release it. After releasing the
appliance re-starts. E9? go to step 5
7.▶ Disconnect lead to CH flow safety temperature limiter.
▶ Measure the CH flow safety temperature limiter for continuity. Resistance small?
yes:▶ Connect CH flow safety temperature limiter. go to step 6
no:▶ Change CH flow safety temperature limiter.
▶ Connect CH flow safety temperature limiter.
▶ Switch ON the appliance.
▶ Press the reset button for 3 seconds and release it. After releasing the
appliance re-starts. E9? go to step 6
8.▶ Disconnect the boiler power connection.
▶ Unplug connector of harness that connects the limiters to PCB from control board. Test harness (including the two limiters) for continuity.
Resistance small?
yes:▶ Reconnect connector. go to step 7
no:Harness defective.
▶ Repair or replace the harness.
▶ Reconnect the appliance power connection.
▶ Switch ON the appliance.
▶ Press the reset button for 3 seconds and release it. After releasing the
appliance re-starts. E9? go to step 7
9.▶ Disconnect the boiler power connection.
▶ Remove fuse SI 3 from appliance PCB control
board and test for continuity. Is there continuity?
yes:▶ Remount the fuse.
▶ Reconnect the appliance power connection.
▶ Switch ON the appliance.
go to step 8
no:▶ Change the fuse.
▶ Reconnect the appliance power connection.
▶ Switch ON the appliance.
▶ Press the reset button for 3 seconds and release it. After releasing the
appliance re-starts. E9? go to step 8
10.The PCB is damaged.▶ Make a note of the altered service settings.
▶ Switch OFF the appliance.
▶ Disconnect the boiler power connection.
▶ Change PCB control board.
▶ Reconnect the appliance power connection.
▶ Switch ON the appliance.
▶ Restore service settings previously noted down.

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