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Discuss Water heater help! in the DIY Plumbing Forum area at PlumbersForums.net


Hoping someone can help! Not sure what else to try.

We have a Vaillant eco tec boiler and we also have a Vaillant auro stor water heater, but for the last two months all of our hot water is coming out Lukewarm. When we first moved in it worked perfectly and the water was super hot. Our heating works fine, the radiators are super hot so our thinking is that the issue is the water heater and not the boiler.

We've tried restarting it, updating the settings, turning up the temperature on the boiler. But nothing has worked. There's a pressure gauge near the heater (pictured) and the needle is all the way down, could this be the issue? The pressure on the boiler is fine, and we know how to repressurise that, but this one doesn't seem to have the same knob so we can't work out how to repressurise. Or could it be a different issue entirely?

Separately, our electricity bill seems unusually high for a one bedroom flat. So we're wondering if this could be linked? Is the water heater working too much and driving up the electricity cost? We have the water heater switch on all the time, should we not? It's timed to heat up a few hours early morning and a few hours in the evening.

I hope someone can help, it's driving us a little mad


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Gas Engineer
I can’t seem to see anything obvious, only a valve under where the pressure gauge is, so it’s either there and you need to connect a braided hose, or that’s a drain off point.


Staff member
S. Mod
Gas Engineer
Can you take a picture of your boiler ? Eg it’s not any of the above pictures

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