I replaced my trusty of old basic electric Potterton Kingfisher with a Vitodens 200 system boiler some months ago. And it works just fine. However, I miss having the external programmer of old - if I wish to switch things off when going away etc it means going to the boiler itself. Viessmann reckon the way round this is to use an extra external controller
- using the room stat circuit - and leave the internal one set to constant. Which isn't really what I want. Apart from the unnecessary cost. The integral controller has a four pin plug for everything - so I'm assuming DC and a data circuit. Any reason why I shouldn't just extend this and site the programmer where I want it - the cable run would only be a metre or so. Or any other suggestions? Other thing is the existing old programmer is mounted on a tiled surface and if I remove it it will leave holes. And I've no spare tiles. But dislike having an unused device left in place.