We fitted electric underfloor heating back in about April, and over
the last couple of days i've noticed the LCD display is _very_ faint
(possibly a bad connection ?!?) - but it seems OK when i've checked it
overnight when it's normally in a sort of "top up" mode

Do LCDs tend to suffer if the ambient temperature is low ? - the
controller is in an ante-room, which is basically a small square with
a tumble dryer and a single glazed back door with a huge sodding dog
flap to let the mutt out, so if ambient temp can be a problem for it,
it might not be a "real" issue to worry about :-}