The W-B Greenstar 29HE installation manual shows a "Y-S wiring module" with a connection called "DV" or "Boiler/pump demand" but doesn't explain what this does. Am I right in thinking that it's an input to enable the boiler to fire only when the pump is running?
The FAQ mentions outside weather compensation but I can't find any details on the web, can anyone enlighten me about this?
Can anyone suggest a cheap basic 3 channel programmer?
Don't know for sure, but could the Y-S wiring module be a junction box where all the electrics are connected when the boiler is part of a Y-Plan or S-Plan heating system? [See
Again, I don't know what DV stands for but, if it's in an external wiring centre, it sounds like the point where the boiler and pump are connected. Alternatively, if it's on the boiler itself, it could be the connection which allows the boiler to control the pump (not the other way round!) by means of an over-run stat.
Do you have a URL for an on-line version of the manual? I had a quick look on the W-B site, but couldn't find any manuals.
Thanks for the honeywell link, v.useful. DV is on the boiler and connects to "Boiler/pump demand" in the wiring centre (the manual is at:
Can you give me a page number to look at in the manual, so I don't have to read it all?!
Page 22. Having read it again it's wired to the pump, the boiler can get the pump running AND the controls can "enable" the boiler. The permanent Live input will be to power the electronics in the boiler.
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