Posting a message to the forum will remove the above advertisement
  1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  2. Checkout our Plumbers Insurance area - heavily discounted Public Liability Insurance and Van Insurance specifically designed for plumbers.

Discuss One boiler and two controllers in the Central Heating Forum area at

  1. Ilija

    Ilija New Member


    I’ve got Valliant combi boiler converted to system. Downstairs I have underfloor heating with Heatmiser thermostats and upstairs I use Nest (which also seems to be controlling hot water). The problem is that upstairs heating will only work if one of the zones downstairs is calling for heat. Unfortunately the two controllers were installed by two contractors during house renovation so now I have to try to figure it out if this issue can be resolved at all.

    Btw, I’m a home owner, not plumber or gas engineer.

    Is anyone here able to offer advise please?

    Thank you in advance!
  2. Chuck

    Chuck Well-Known Member

    A competent heating engineer will be able to sort the problem out for you. Probably best to check that they are familiar with Nest before booking but most are these days. I would expect it to be trivial to get the upstairs zone to provide the boiler with a demand signal.

    What will be harder is to make sure that the zones are synchronised appropriately so that the boiler doesn't 'short cycle'. There are several possible approaches to this task, each with their pros and cons, so you need someone with appropriate experience to advise you.

    For this sort of thing, I suggest you get a small local independent heating-engineer who has been in the business for a good number of years and has been recommended by someone you know.
    • Agree Agree x 2
  3. Ilija

    Ilija New Member

    Hi Chuck. Thanks for quick reply. I’ll try to get hold of a reputable engineer.

    • Useful Useful x 1
Similar Threads - boiler controllers Forum Date
Noisy boiler (Rubbish Ferroli HE18) Plumbing Forum Yesterday at 4:36 PM
Has my builder ruined my boiler? Central Heating Forum Tuesday at 9:26 AM