In article . com,
Thomarse wrote:
You make it sound very simple, and Im sure on face value when I look at
it, it will be simple, but I do get a little bogged down when it comes
to circuit diagrams and the type of system which I have, I basically
dont know what system I have. My concern is that having read other diy
forums, replies tend to say "if you have this system wire it this way,
and if its this system wire it this way".

If the old one worked ok then all you have to do is wire the new one the
same. Most basic programmers are simply two changeover relays operated by
the timer mechanism. A changeover switch is the same as a lighting two way
switch - one common terminal which is the input in this case, and two
output terminals - one which is made with the relay off, and the other
with it on. The 'off' one isn't required on some installations. The common
terminals are often both wired to the incoming line so in practice you may
only have two to be confused over. ;-)

Like all electrical circuits, it helps to 'break' them down into the
simplest of blocks no matter how complicated they look at first. In this
case you have three such blocks - the 'motor' which controls two
changeover switches.

--
*What was the best thing before sliced bread? *

Dave Plowman London SW
To e-mail, change noise into sound.