Changing thermostat

Discussion in 'Electricians' Talk' started by Steven Sandell, Oct 11, 2018.

  1. Steven Sandell

    Steven Sandell New Member

    I recently purchased a new thermostat for combi boiler, looking at the old one there's a brown wire going to l and and blue cable going to l1, the new thermostat has N, L, dry and contact.
    Where do the wires go please...
     
  2. Bazza

    Bazza Screwfix Select

    Dry, contact? What's that mean?
    Pictures of the wiring of the old and the terminals on the new one please.

    If that's difficult, the make and model number of both devices.
     
  3. Steven Sandell

    Steven Sandell New Member

    Here's the new thermostat
     

    Attached Files:

  4. Allsorts

    Allsorts Super Member

    Are you sure that Stat also has a built-in sensor? Because it does look as tho' it's designed for UFH with a remote sensor.

    Anyhoo, wiring that one ain't the problem - the problem is what wires do you have, and where did they go on the old stat. If you really only have two wires, then I believe you are stuffed and will need a battery-operated Stat.

    Can you post a pic of the old one?
     
  5. Steven Sandell

    Steven Sandell New Member

    This is the old one
     

    Attached Files:

  6. Allsorts

    Allsorts Super Member

    Cheers.

    What's the front like? And does it take batteries?
     
  7. Steven Sandell

    Steven Sandell New Member

    Front and yes does take batteries
     

    Attached Files:

  8. Bazza

    Bazza Screwfix Select

    The new thermostat needs a neutral, and you haven't got one. And as above post #4, it looks like the wrong stat anyways. (Make/model numbner will help.....)
    Whatever the outcome of that, If you are going for a digital stat, you are either going to have to rewire it, or get a stat that takes batteries.
     
  9. Bazza

    Bazza Screwfix Select

    That's the old one isn't it?

    Its the new one we need the info on.
     
  10. Steven Sandell

    Steven Sandell New Member

    Box for new one
     

    Attached Files:

  11. Steven Sandell

    Steven Sandell New Member

    Face of new stat
     

    Attached Files:

  12. Bazza

    Bazza Screwfix Select

    This is hard work

    What is the
    MAKE and MODEL of the new thermostat??
     
  13. Allsorts

    Allsorts Super Member

    Steven, that new stat won't work without an additional neutral wire since it doesn't run on batteries.

    Yes, it looks nice, But I would suggest an alternative, one that is battery-powered. If you insist on keeping it, then you'll (a) need a further wire installed and (b) need to confirm that is has a BUILT-IN heat sensor to detect the actual room temp.

    It may have, but it isn't certain.
     
  14. Steven Sandell

    Steven Sandell New Member

     
  15. Steven Sandell

    Steven Sandell New Member

    It does have a neutral wire but has been cut short and not in use, apologies for my vague replies
     
  16. Steven Sandell

    Steven Sandell New Member

    Info
     

    Attached Files:

  17. Steven Sandell

    Steven Sandell New Member

    Info
     

    Attached Files:

  18. Steven Sandell

    Steven Sandell New Member

    Wiring
     

    Attached Files:

  19. Bazza

    Bazza Screwfix Select

    I’m sorry, Steven. The cable to the existing stat has only live, boiler call and earth.
    There is no neutral in that cable.
    Ps. The wiring diagrams show, in all cases, a temperature probe being attached. I don’t know if that is what you expect?
     
  20. Steven Sandell

    Steven Sandell New Member

    Oh dear unsure what to do next..
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice