Valliant EcoTec Plus 831 always On!!

19 Mar 2010
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United Kingdom
Hi Guys,

I have joined this forum because i am in desperate need of advice and a solution,

I have recently done up my house including new Radiators and Boiler which is the Valliant EcoTec Plus 831. Recently i have noticed the Tap symbol is always on, and the Boiler will use Gas even thought nobody is using Hot water.

I have had the Flow sensor replaced and even a No return valve installed however that brought no joy :cry:

Does anybody know why this has happened and a possible workaround or fix?

I currently have to close the valve that brings in water to the boiler this will get rid of the Tap Symbol, but is anoying and my Gas bill as gone up

I would appreciate some suggestions thanks allot :)
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Are you sure because no taps are leaking, and when the pipes were installed they did not appear to be leaking. When I open the cold water inlet valve the tap symbol appears and will not go away until I close the same cold water inlet valve. I have been doing this to save gas :cry:
Sure. You've proved it by turning off the service cock and seeing the tap symbol dissapear. The tap symbol means it is detecting flow of water, so when u turn off the mains the flow stops.

All you can do is trace the leak
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This may sound silly, what's the best way to trace a leak? Check all hot water pipes that go from the boiler to taps? Thanks looks like I will have to look behind the kithen units :(
It will have to be a hell of a leak for a Vaillant to lock into HW mode :rolleyes:
That's what I was finking, I can't hear a leak, or see any puddles of water ?
Go into d codes see what flow is registering also s code will tell what boiler is doing if no leak on system could be plate h/exch passing into system, check prv for leak.

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