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    • Hedgehog99
    • By Hedgehog99 5th Dec 17, 12:03 AM
    • 1,394Posts
    • 2,890Thanks
    Vaillant Home System 12: How to top up?
    • #1
    • 5th Dec 17, 12:03 AM
    Vaillant Home System 12: How to top up? 5th Dec 17 at 12:03 AM
    The pressure is flashing, alternating displaying 0.4 and 0.5 bar.

    All the instructions say is that I should have been shown by the competent person how to top up the hot water system (I wasn't given any hand-over on this system). Neither manual (user/installer) has a decent diagram of the system & its connections.

    I'm used to using the filling loop system on a combi in my previous house, but I see nothing that looks like that here.

    I have identified, left to right underneath the boiler:

    1)Condensate siphon
    2)Heating flow connection G3/4
    5)Gas connection G1/2
    7)Heating return connection G3/4


    The "*" is a mystery metal pipe, smaller in diameter than the heating connections. It has no taps etc on it.

    The "?" are two identical-looking connection points to the boiler (i.e. same black rings as where heating pipes connect etc), but are capped off with translucent plastic caps.

    Both heating connections have screwdriver slots on the front.

    Can anyone confirm from this description how to fill the system and if everything needed to do so is present?

    It's a new system, under guarantee, so I can call the engineers, but it'll be a while before they can come so if it's something someone can answer on here, all the better.

Page 1
    • bris
    • By bris 5th Dec 17, 2:47 AM
    • 7,592 Posts
    • 6,610 Thanks
    • #2
    • 5th Dec 17, 2:47 AM
    • #2
    • 5th Dec 17, 2:47 AM
    Look for a filling loop near the tank/cylinder.
    • Hedgehog99
    • By Hedgehog99 5th Dec 17, 8:22 AM
    • 1,394 Posts
    • 2,890 Thanks
    • #3
    • 5th Dec 17, 8:22 AM
    • #3
    • 5th Dec 17, 8:22 AM
    Look for a filling loop near the tank/cylinder.
    Originally posted by bris
    Thank you :-)

    Found it in the airing cupboard this morning with a nice helpful label on it!

    So used to my previous combi, I hadn't thought it could be in the airing cupboard!

    Heating back on
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