replying to rocky, Wirdy wrote:
New answer to an old question, but maybe useful for anyone now searching for
an answer. If your Worcester CDI stays in air purge mode, it's likely that the
control value (2c in engineer mode) has been set to '2'=permanently on. You'll
need to go into the service menu and check the stored value of the air purge
mode . It is normal to set it to 1 on a brand new boiler or after maintenance,
this causes a 8 minute purge cycle whereafter the value automatically reverts
to a zero (air purge off). The procedure for going into the servicing menu is
in the engineers manual for the CDI range of boilers and is available online
if you search for it. If you're not confident reading an engineers manual and
pressing buttons to control menus then best left to an engineer. Don't go
changing other values apart from 2c or doing a factory reset as the other
values stored are set up by your installing engineer for your particular
installation.

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