Isolate boiler

[omph]

I need to drain down the boiler (not CH) and replace the divertor valve. I've done loads of plumbing but never really isolated and drained the boiler before. I can see the CH pipes under the boiler, which direction do I need to turn their isolator values to close the circuit ?

Also, how do I identify where the drain point is and how to open it ?

And is there is a bleed value I will need to open when refilling the boiler ?

The boiler in question is a viessmann 100-w,

 

[Madrab]

Not what you want to hear but unfortunately as the 100-w has a room sealed case, it wouldn't be recommended for anyone to remove the case that wouldn't have the correct equipment/experience to check the boiler once the work has been completed. This is purely a safety consideration.

 

[omph]

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