Viessmen 100T boiler wired within a Sunday Plan

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I'm with steps on this one, why would you use the hot water side?


You cannot use a 2 port valve on a Y plan, because then it isn't a Y plan. It is a physical impossibility.

I know I'm just speculating as to what has been done to resolve it..

There are various ways of using the stat, which actually has 2 thermostats in one housing. TBH if you are not really familiar with heating systems in general (which it doesn't sound like you are) then it is probably best to leave these types of things to those in the know.

I've done plenty of combi boilers and numerous s plan systems all without problems but this set up and the reason it wasn't operating puzzled me..

Would you walk away from a job if it wasn't something that you were totally familiar with or would you look at the diagrams and try and work it out ??

Without seeing the entire system I couldn't really say what you did wrong exactly, so I will not try and guess how it should have been wired.

 
Would you walk away from a job if it wasn't something that you were totally familiar with or would you look at the diagrams and try and work it out ??


But you didn't know what you were doing, had a go then left anyway. That is sub-standard at best, more like something on Rogue Traders.

I have done plenty of jobs where I have learned on the job, but what have you learned here? You are meant to learn, then do the thing you have learnt, not guess then go away and ponder.

I have also walked away from jobs that have involved doing things that I am not familiar enough with to offer a decent service.

 
But you didn't know what you were doing, had a go then left anyway. That is sub-standard at best, more like something on Rogue Traders.

I have done plenty of jobs where I have learned on the job, but what have you learned here? You are meant to learn, then do the thing you have learnt, not guess then go away and ponder.

I have also walked away from jobs that have involved doing things that I am not familiar enough with to offer a decent service.
Wrong..I wired the boiler and all was OK, the plumber hadn't provided a cylinder demand terminal box so I left  waited for the call to say it had arrived and went back and installed it.

Went back and found the hot water demand wasn't switching off so attempted to resolve it by calling viessmann but the tech helpline was shut it was 7pm at night..

The plumber was due back the following day and said he'd get in touch with my boss I'm not self employed I get told where I'm going..I left the hot water off at the programmer and turned the immersion heater on..

The plumber went back 3 days later as he had a job in the area where another electrician he works with was also working on...he got it sorted after 3 hours on the phone with viessmann and this electrician  has worked on the plumbers boilers for years so it didnt appear to be a straightforward fix apparently all of the wiring diagrams on site were of no use to me...

I don't appreciate the rogue trader comment I take pride in my work and do give a **** hence why I'm on here at 22.25 discussing it..

In fact I've offered to go back in my own time to have a look for peace of mind and future reference 

 
I'll let you know once I've spoken to the other electrician 
Don't take criticism to heart, we asked for more info and didn't get a lot, so conclusions were drawn instead of diagrams.

Please let us know the details.

 
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