Potterton Promax SL not firing up on Auto

27 Mar 2021
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United Kingdom
Make: Potterton Promax SL

For the past 3 days, I've noticed that my boiler does not start the ignition sequence when calling for HW/CH anymore, there is no whirring sound. I have to press the Reset button for it to begin the sequence and fire up.

I took the casing off just to have a look at the light indicators. Left light flashes red. No light on middle light and On is solid green
(Picture): https://imgur.com/f0wedWy

Is there any troubleshooting advice before calling an engineer?
Last edited:
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