after e1 there will be another 2 nos showing the code will be something like e1 then 10 making it e110. u need the full code.
heres a guide go down to section 5. it will show the faults.
http://www.potterton.co.uk/docs/101209_Potterton_Promax_System_HE_Plus_A_Range_user_guide.pdf
kash
October 2013
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