SWITCHMASTER 400 - Mechanical Replacement

[Whizzard17]

Hi can, anyone recommend a mechanical replacement for the SWITCHMASTER 400? It's for my mum and I can't persuade her to have a digital one. I was looking at maybe this?
Siemens RWB2 24 Hour Mechanical Timer:
https://www.plumbnation.co.uk/site/siemens-rwb2-24-hour-mechanical-timer/
https://www.downloads.siemens.com/d...spx?pos=download&fct=getasset&id1=A6V10464896

 

[stem]

Understood! I had the same situation with my mum, but not just for the programmer. I had to find a microwave with just a mechanical timer dial and power setting dial.

Yes the Siemens will be fine. The only difference is the terminal numbers used for the wiring. The Siemens uses terminal 3 for hot water control, and terminal 4 for central heating control, whilst I think the Switchmaster uses terminal 3 for hot water control, and terminal 1 for central heating control. There are a few variants of the Switchmaster around, but you should find confirmation of what terminals do what marked on it somewhere.

If your mums system isn't designed to allow the central heating to be 'on' without the hot water also being 'on' you should set the Siemens to the 'pumped central heating with gravity hot water' setting.

 

[oilhead]

Drayton SM2 is virtually identical.

 

[dilalio]

Sorry... had to tell you all... when I first saw this thread title, I read it as “SCHITMASTER”

 

[Whizzard17]

Thanks all for your responses