In article ,
Chris wrote:
Thanks for the replies ... Have since found out that the unit is a
Drayton Tempus 7 and on replacing the fuse again - the unit displays
the time etc. OK which you can programme but blows the fuse when the hot
water is turned on by "advancing" or by timing. ( No central heating
turned on)

Trouble is this action could be operating a variety of things - could be
moving a 3 port valve or operating a single one. So more information on
the system needed. Does it work ok on heating only?

--
*Snowmen fall from Heaven unassembled*

Dave Plowman London SW
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