Page 13 of 21 FirstFirst ... 389101112131415161718 ... LastLast
Results 121 to 130 of 205

Thread: Evohome + Opentherm v Evohome + Boiler Outside Weather Compensation

  1. #121
    Automated Home Legend
    Join Date
    Jul 2014
    Posts
    1,001

    Default

    Quote Originally Posted by StuartG View Post
    I have a Vaillant 637 system boiler running with the VR33 and OpenTherm bridge.

    In my case I removed the existing 230V connection that was wired to the BDR91. I connected the VR33 to the expansion board on the side (for me, X31). I also had to reinstate a jumper on the 24V RT connection (for me this was X100, coloured white, and labelled RT24). The boiler installation instructions explicitly say to REMOVE that jumper when using 230V controls. There was a handy little piece of wire in the VR33 box that did just the job. The VR33 instruction (assuming I read the Dutch properly!) don't seem to specifically point this out, presumably because the module could go in various boilers. The installation manual my boiler does say that RT24 might also be labelled X106.

    I too get a confirmation on diagnostic code 90, so it sounds like the module has been recognised.

    I don't know the specifics of how the wiring works inside the boiler, but I am guessing that in the absence of the RT24 jumper then the circuit is broken and hence the boiler never fires up? My understanding is that shorting the OpenTherm connection itself should cause the boiler to fire.

    Hope this helps!
    I too think it's something to do with the 24V connection, but on my boiler it's not marked as such. There are 24V connections called 7 8 9 but the UK never had any controls that used those. There are some boilers that had to switch a diagnostic code (d.20) to switch the boiler from On/Off to Opentherm. But again nothing on that for me.
    My entire installation and all the signs seem to suggest that my OpenTherm module VR33 is installed correctly and is talking nicely to the boiler. No error codes and all the lights are flashing as they should.

    I feel I am close, but yet very far!
    Last edited by bruce_miranda; 10th April 2016 at 11:16 PM.

  2. #122
    Automated Home Legend
    Join Date
    Jul 2014
    Posts
    1,001

    Default

    Can either Stuart or top brake tell me if they can see the target temperature changing on D.009 and also what does D.016 show currently with your 24V RT bridge in place and the VR33 installed? Does D.016 change when there is heat demand or not?

  3. #123
    Automated Home Jr Member
    Join Date
    Mar 2015
    Posts
    45

    Default

    D.009 does indeed vary. I've seen values varying from low 50s to 90C since it's been installed. High values when house is cold / heating up; low values when we're at target and maintaining, which seems logical.

    D016 shows 24V DC Heat Mode: On.

  4. #124
    Automated Home Legend
    Join Date
    Jul 2014
    Posts
    1,001

    Default

    And what does D.008 show?

  5. #125
    Automated Home Jr Member
    Join Date
    Mar 2015
    Posts
    45

    Default

    Controller 3-4 0:Open

  6. #126
    Automated Home Legend
    Join Date
    Jul 2014
    Posts
    1,001

    Default

    How do you guys know if the Opentherm bridge is calling for heat or not? On the bdr91 its dead easy.

  7. #127
    Automated Home Jr Member
    Join Date
    Mar 2015
    Posts
    45

    Default

    I've not actually looked to see what input indicates that the bridge is calling for heat, other than the boiler fires up! Sorry!

  8. #128
    Automated Home Legend
    Join Date
    Jul 2014
    Posts
    1,001

    Default

    Would you be able to? Just want to know if my Opentherm bridge is calling for heat or not? If I know how i can be sure it is calling for heat then I can move on to working out why the boiler isnt responding or ignoring that command.

    Having read (too) many manuals last night it seems that eBUS modules are registered automatically and the boiler 'knows' that it has to listen to them. But its not doing that with my VR33 even though the boiler recognised it as an eBUS device.
    So either the VR33 is issuing eBUS commands that my boiler cant understand or I need to bridge something else (similar to what the 24V RT) is.

    If only there was a way to look at the eBUS traffic on the boiler. There is an eBUS diagnostic port on the boiler.

  9. #129
    Automated Home Legend
    Join Date
    Jul 2014
    Posts
    1,001

    Default

    Are any of you using the VR65 or VR66 wiring centre?
    According to Vaillant you will need a wiring centre to use ebus controls with the 400 and 600 series’ ecoTEC boilers.

    I dont have this. I simply have a 230v Honeywell S plan wiring box.

  10. #130
    Automated Home Jr Member
    Join Date
    Mar 2015
    Posts
    45

    Default

    No - everything was originally wired using a standard Salus wiring centre. When I reconfigured it to use OpenTherm it was just a case of disconnecting the boiler relay BDR91 and putting the OpenTherm bridge in its place.

Posting Permissions

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