replying to Tobin Harris, LC B wrote:
Additional info...
I tried changing the fuse, but with no difference. When the controller is off
at the socket, the LCD panel dims, and when I turn it back on, the panel gets
brighter/stronger. This suggests there is mains power getting to it, but the
buttons aren't working!

16 years later, but in case anyone out there still has this old Sunvic timer,
the SP35, I've come across a problem.

It had been setting the automatic central heating up to three times per day,
on and off, perfectly. However, then the electricity went off (I think not to
do with this timer) one day, and since I can't get the timer to work.

It's to do with the Mode setting at the side of the digital timer. The mode
allows you to switch between ways of using the heating - on continuously,
automatically timed, on once (then not automatic after the next timed section
ends), or off altogether.

The Mode is stuck on Auto, and it won't move. If I try to move it, the whole
programmed set up of on and off times per day, and also the current day and
time for the timer, resets - all to 12.00 am on Monday.

I should press Mode repeatedly to shift between the different modes in a
circular pattern. But it is stuck and Mode, though shifts quickly to
continuous and back to Auto, when it's resetting everything.

I'd be happy with the timer stuck at Auto, because what I want is to use the
automatic timer. However, it's not bringing the timer on at the set times.

I've tried changing the batteries just now. This may be an entirely separate
point, it probably is. There is a pull out slot for two AA batteries. I just
changed them. It looked to me like they may not be touching a connection at
one side, so I added a bit of aluminium foil to each battery as I've done many
times before, and they both seemed to fit a lot more snug.

I just happened to pull the tray out again 10 minutes or so later, and these
batteries were each as hot as a cooker hotplate. The Duracell plastic was
molting off them, leaving just the extremely hot metal underneath. I used a
plastic ruler quickly to wedge them out of the tray safely, and also the alu
foil bits without touching that.

Safe again, but I've no idea what that is about. In any case, I think that the
batteries are just to remember the programmed timings should the electricity
go off unusually. This nearly never happens, so it wouldn't be a problem, and
it's fine to reprogram the timer settings anyway if it would - it just takes a
few minutes.

Whether or not that is related to that the timer just won't do the automatic
timing function, I don't know.

If anyone has had this problem, or knows generally of why it might be with a
timer such as this old digital style one, please post.

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