Vallaint Combi Turbo Max Plus loop valve pressure adjustment

28 Sep 2015
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United Kingdom
Hi,I have a Vallaint combia turbomax plus 824e boiler. The water pressure keeps drooping to 0.2. I have had a plumber in before to look at it and he increased the pressure of the loop valve with a key because the screwdriver head directly on the valve is very worn out making it impossible to adjust with a screwdriver. I am trying to find this key with recesses into the valve and allows me to adjust the pressure but I can't find one online anywhere. Would you be able to help me with this in any way ? Many thanks
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Possibly an allen key. Can you post a photo?
Unfortunately for you, your boiler has probably the worst filling link design ever!

But don't worry the key is available here:

And if the valve is too damaged for the key to work, you can get the whole valve here:

However. If you are having to top up regularly. You need to get an engineer to diagnose why. It could either be a leak somewhere on the system or a problem with the expansion vessel or prv inside the boiler.

Regular topping up is not good for the boiler and system.
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Thank you very much you have helped a lot. Is there a better valve loop I could have installed ??
You could have an external one fitted, it would be much easier to operate, but you would need a plumber to install it so best just to get a new key for the one you have now.
That's what I was thinking Bunnyman, but knowing how there are several different systems sometimes its easier to just keep quiet in case I am wrong in this particular case!
I must be thinking of an earlier filling link. I'm sure there was a vaillant one around that was just 2 big round slotted screws, rather than the smaller square version? It came with a slotted key that was useless. i'm sure bunny will correct me if i'm wrong
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