How to refill Vaillant Turbomax plus


20 Nov 2005
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United Kingdom
I have moved into a house with a vaillant turbomax plus 824. The pressure when cold is very low (0.2). I have looked at the manuals, and it says the boiler needs refilling. However, the diagram in the installation manual on how to fill up the system looks nothing like mine! Is there suupposed to be a filling loop and key? I can't seem to find it. Any help will be very much appreciated!!! Also, is there supposed to be an automatic air release valve somwhere??!
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Filling loop is incorporated into bottom of boiler. there should be a small key projecting which you turn to open - close when pressure reaches 1.0 bar or a bit over. For more info do a search on this forum - it has come up before.
Thanks! I did a further search, and it all became clear. My key had obviously fallen out, and I had to valves which could be turned using a screwdriver. Opened one valve and then the other and waited for the right pressure, then turned them both off again. Thanks a million!
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Helpful post this one. Fixed my problem. :)

I have a Vaillant turbomax plus 824e/2.
Apparently this is the appropriate manual:
Which shows this for re-pressurizing the central-heating :

This seems wrong, or out of date, for me too.
In my case there are valves turned by a screw, no sign of ever being a tap/handle.

I had an apparently F.28 (supposed to be a gas supply problem, p77) but was also seeing low Central-heating pressure.
So re-pressurized, and all was well.

To re-pressurize turn both the highlighted (in above image) valves 90 deg to get around 1.5 bar.

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