Hi I have a very old SWITCHMASTER 400 timer and I'm looking to replace it with an electronic programmer.
It's a 24 hour mechanical timer with an Off/Timed/Constant switch and Water/Heating & Water switch.
I want to change it for a 7 day electronic one and also to be able to control the water and heating independently if possible.
I've seen a CentaurPlus C27 on TLC http://www.tlc-direct.co.uk/Technical/DataSheets/Horstmann/C11.htm which ticks all the boxes but I'm not sure if my current wiring will allow me to do this.
The terminals on the back of the timer are N L 1 2 3 4 with 1 being CH On, 3 being HW On and 4 is CH Off. 2 is blank.
Apart from Live, Neutral and Earth only 1 and 3 are wired.
Firstly, am I able to direclt replace it with the CentaurPlus C27 - WITHOUT ADDITIONAL WIRING?
Secondly, why is terminal 4 not wired? Is this what a 'Single Circuit System' is?
If I can't use the C27 would the C17 do?
Sorry for all the questions but the more info I'm reading the more confused I'm getting!
Cheers
Boff
It's a 24 hour mechanical timer with an Off/Timed/Constant switch and Water/Heating & Water switch.
I want to change it for a 7 day electronic one and also to be able to control the water and heating independently if possible.
I've seen a CentaurPlus C27 on TLC http://www.tlc-direct.co.uk/Technical/DataSheets/Horstmann/C11.htm which ticks all the boxes but I'm not sure if my current wiring will allow me to do this.
The terminals on the back of the timer are N L 1 2 3 4 with 1 being CH On, 3 being HW On and 4 is CH Off. 2 is blank.
Apart from Live, Neutral and Earth only 1 and 3 are wired.
Firstly, am I able to direclt replace it with the CentaurPlus C27 - WITHOUT ADDITIONAL WIRING?
Secondly, why is terminal 4 not wired? Is this what a 'Single Circuit System' is?
If I can't use the C27 would the C17 do?
Sorry for all the questions but the more info I'm reading the more confused I'm getting!
Cheers
Boff