Sorry but Vaillant are the experts they have attended and worked on the unit, you can only keep up dialogue with them, I dont see how you expect someone on here who has never worked on your unit to know more than Vaillant do
But they have prooved they do know more! (in 24 hrs!). Not one Vaillant person, 3 tech dept phone guys, customer care dept, 6 engineers on 11 visits, inc the head uk engineer in a suit here.. has once said the words 'frost protection' in 6 months. I twice threw the idea out to them, but i got shaking of heads "no not frost protection, it would say that on one of the screens". You see?
I get a slew of different ideas of what it might be, from all of these guys, but not 'frost protection'. Then the unit gives me clues, on its screens at the very time of these periods, but not ever 'frost protection'.
Frost protection: some kind person on here has spotted the 4*c fig, which being close to 3.5*c i know it trips on at, my only clue to what it is actually doing...... is now the likely suspect (after months of detective work by Vaillant & me). Kudos to diynot. But its only a possible. I have to go with this possibility or i cannot progress, &, it seems increasingly sensible to do so.
So I've finally finally found what it is doing (lets just say). Right!! onto step 2 itching to continue. But im stuck here. You see I've got to get to step 4, making it stop.
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The core reason Im here, is because Vaillant have been 100% hopeless on this. They tell me its not frost protection, & dont know what its doing, then blindly throw answers at it 'we have new boards to fit', which do nothing. Replaced pump, does nothing. Sending guys time after time tinkering with settings saying "that'll be it" driving off, doing nothing. Get me to plough thru settings call after call try this try that, weeks of it.. doing nothing. They've no clue. Too new a system? Not thorough enough training? Seems to me.
If they never themselves mentioned 'frost protection' once (incredulously)...... by all accounts then, they were never ever ever ever on the correct page to remedy it, none knowing what the problem is!
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Therefore, I come here in desperation to ask: 1) what it might be doing in your opinion (DONE, well most likely done that is: a massive achievement 6 months trying... so Im itching to go on!) because Vaillant cannot establish what, & now giving up i can tell, & installers given up on what it is doing long ago.
2) maybe explore ideas on how to tweak settings, or, diy entertain a plan to fix it (tantalisngly hinted at but Im left teetering on a cliff hoping someone might help a little more)..
Or 3) offer help with ideas in trying to tackle this company as i have no experience (citizens advice? Any opinions? Solicitors? It's my last resort): Trading Standards was mentioned, appreciated, looking into it.
So my plan of attack is try 1 first, then 2.
Thx. SC.