Results 1 to 4 of 4

Thread: Adding UFH to EvoHome Y-Plan

  1. #1
    Automated Home Lurker
    Join Date
    Jan 2018
    Posts
    7

    Default Adding UFH to EvoHome Y-Plan

    Hi,

    I’ve got an EvoHome Y-Plan system that I installed myself. I’ve done it exactly as per the book, with a BDR91 relay on each side of the 3-port valve. Wiring in the 10-way junction box is as per page 47 of the installation guide. Initially I was thinking that at some point I might add a third relay for boiler control, but the default TPI is working fine for me anyway.
    All the radiators have HR92s on them apart from the Bathrooms which have retained their TRVs. The hot water cylinder has the CS92 hot water kit fitted. The boiler is a traditional system boiler, however it’s running with an external expansion vessel in the loft rather than a tank. The pump is set to a fixed speed. I do not believe that there is an automatic bypass valve. (And yes, with most of the radiators closed the valves whistle a bit)

    We’re looking at having the Kitchen done. Not just units but some building works too and as part of that having warm water Under Floor Heating fitted to the newly enlarged room rather than the existing HR92 radiator. The Kitchen work will be done by a local indie (not the big chains!) and they will be managing the trades.

    I'm not expecting their plumber will know EvoHome, so before speaking to their plumber I’d like to get my head around it first...

    What’s the best way of adding in UFH into an existing Y-Plan system and then controlling it with EvoHome?

    I'd like to do it properly and if that means additional complication in converting to S-Plan 2-port valves with automatic bypass etc then so be it - I'd rather it was done the best way than any cheap bodges.

    Thanks!

  2. #2
    Automated Home Legend
    Join Date
    Mar 2017
    Posts
    507

    Default

    Quote Originally Posted by Westyfield2 View Post
    Hi,

    I’ve got an EvoHome Y-Plan system that I installed myself. I’ve done it exactly as per the book, with a BDR91 relay on each side of the 3-port valve. Wiring in the 10-way junction box is as per page 47 of the installation guide. Initially I was thinking that at some point I might add a third relay for boiler control, but the default TPI is working fine for me anyway.
    All the radiators have HR92s on them apart from the Bathrooms which have retained their TRVs. The hot water cylinder has the CS92 hot water kit fitted. The boiler is a traditional system boiler, however it’s running with an external expansion vessel in the loft rather than a tank. The pump is set to a fixed speed. I do not believe that there is an automatic bypass valve. (And yes, with most of the radiators closed the valves whistle a bit)

    We’re looking at having the Kitchen done. Not just units but some building works too and as part of that having warm water Under Floor Heating fitted to the newly enlarged room rather than the existing HR92 radiator. The Kitchen work will be done by a local indie (not the big chains!) and they will be managing the trades.

    I'm not expecting their plumber will know EvoHome, so before speaking to their plumber I’d like to get my head around it first...

    What’s the best way of adding in UFH into an existing Y-Plan system and then controlling it with EvoHome?

    I'd like to do it properly and if that means additional complication in converting to S-Plan 2-port valves with automatic bypass etc then so be it - I'd rather it was done the best way than any cheap bodges.

    Thanks!
    Remove the Three port valve, fit a two port to the hot water circuit. Heating circuit doesn't need a valve as HR92s on all rads, use the now redundant BDR91 from the heating control as a boiler relay. Purchase a Y87RF2024 for the UFH (assuming it is one zone) and bound as an extra zone. Personally I would have a motorised valve on the UFH manifold without actuators, however you could have no motorised valve and just actuators.

  3. #3
    Automated Home Sr Member
    Join Date
    Oct 2017
    Location
    France & UK
    Posts
    74

    Default

    You will also need to wire the ufh mixing pump to either the bdr or the other option is via the switch output of the zone valve( if fitted) . With no zone valve I guess all actuators would have to be wired to the bdr.

    When I installed our ufh system I was recommended by the supplying company to install a zone valve (which I wired in parallel with the ufh mixing pump) , despite the ufh zones being controlled by acutuators via a hcc80 . Not entirely sure why although the system works impeccably well with evohome.

  4. #4
    Automated Home Legend
    Join Date
    Jul 2014
    Posts
    2,307

    Default

    it's so much cheaper just using a T87RF and a BDR91 to control the zone valve to the UFH. Ofcourse only works if the entire manifold is working a single zone.

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •