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Discuss Problem with logic 35 water part 2 in the Plumbing Forum area at

  1. Rotor

    Rotor New Member

    Evening gents

    First off thanks for everyone who contributed on my first post.

    I’ve had a engineer out to look at the problem who spoke to ideal technical and he thinks it is either the heat exchanger or the diriviter valve. He is coming back with prices, although he did mention sometimes it’s better biting the bullet and going for a new boiler . If I was intended on keeping a combi I would have no hesitation in changing and upgrading to a top line boiler.

    Anyhow it got me thinking I’m going to be changing the heating setup next summer when I extend . I’ve been looking at a mega flow eco system ready 250l unvented water cylinder , I’ve not spoken to the engineer yet but do you see a problem on the plumbing side ? ie connecting a combi into a unvented water cylinder. Would think the hot water output on the boiler capped off . The control side/ Electrics are no problem as I am an approved electrician

    Thanks again guys I look forward to your input
    Last edited: Oct 20, 2018
  2. scott_d

    scott_d Plumber GSR Top Contributor!!

    What's the question?
  3. Rotor

    Rotor New Member

    Thanks Scott

    Would you have an issue plumbing into a water cylinder off a combi boiler ?
  4. Riley

    Riley S. Mod Trusted Plumber GSR Top Contributor!!

    No but I believe you must keep one outlet running off the Combi hot water
    • Like Like x 3
  5. scott_d

    scott_d Plumber GSR Top Contributor!!

    It can be done but as above, needs a hit outlet, possibly a bypass, possibly additional expansion
    • Like Like x 1
  6. Rotor

    Rotor New Member

    I take it the engineer should know all this
  7. scott_d

    scott_d Plumber GSR Top Contributor!!

    You would have to ask. If he doesn't know then find someone else.
    • Like Like x 1
    • Agree Agree x 1
  8. AMGasServices

    AMGasServices GSR

    Yes it’s possible. I’ve done it at home.

    Make sure the engineer is G3 qualified or else you could’ve wasting your time. As stated by Scott.
    • Like Like x 1
  9. king of pipes

    king of pipes Trusted Plumber GSR

    Can be done but keep the kitchen hot tap , utility or cloak room hot supplies off the combi , and use the Mega flow to supply your bathrooms you will need a separate 22mm cold water supply with 20 + litres a minute and 3bar pressure for the cylinder get your installer to check your mains cold supply you may wish to consider upgrading especially as your extending your home . Cheers kop
    • Like Like x 2
  10. scott_d

    scott_d Plumber GSR Top Contributor!!

    Post your location
    Someone on here might be local and can give you a quote
  11. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    hes in Falkirk
    • Informative Informative x 1
  12. dan_the_plumber

    dan_the_plumber GSR

    Why have you got to have one hot tap supplied by combi please?
    • Useful Useful x 1
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