Where does the 4th wire go? Help

collette

I am resorting to this forum as despite numerous messages and emails I still have not had an answer to a simple question and now have no heating

This is not a great start to my purchase

I have a newtec ty_90b/c and am replacing it with a v3 starter wired.

My boiler is a Worcester com I 35 cdi.

I have an additional wire in my newtec a green/ yellow and don’t know where it goes in the tado. Does anyone know?

My review of the product / service to date is zero , I am hoping this improves as I bought 9ne for my son which is yet to be fitted.

PLEASE HELP

Thanks

policywonk

@Collette
A few things need to be clarified.
1. What is the exact model of the programmer? You say it is a Newtec ty_90b/c. I couldn't find this brand name anywhere on the Internet. There are Newlec products, but that term ty_90b/c shoes not lead to a result. There could be a typographical error. Please clarify.
2. Please take photos of the back of this programmer so we can see how the current wires are placed. Post those photos via a laptop browser not a mobile phone browser.as your photos can be uploaded for us to see.
3. There are many models of the 35 cdi boiler. Please confirm that this is a combi boiler and that you are intending to apply the tado thermostat to control your central heating only.
4. Please take a photo of the front of the boiler and post it here.
We will try to help.

collette

thanks for replying

1_The thermostat is a newlec apologies Ty 90 B1
2- photo attached

IMG_9120.jpeg

3_The boiler is a combi boiler.Worcester Bosch
Using tado for heating only

Thank you

policywonk

This agent, Campini, now handles the rights to that thermostat. Campini Corel TY90.T3 Tamperproof Room Thermostat. According to them, the wiring diagram of your thermostat is printed on the inside of the front cover. Would you have a look at that, and if it is there, please take another photo, post it here and we'll be moving quickly.

If that diagram isnt there. This link: 8 716 145 143b. 35cdi installer - provides the installation guide for your boiler. Now go to Page 9. It presents in Figure 10, a connection point, marked as item 4. A blown up picture of the connection point is shown in Figure 12. Take a photograph of that connection point, it will identify how the following cables are wired:

• Permanent Live leaving the boiler
• Switched Live coming back from the thermostat
• Neutral.

You may find that the cable wired into that connection point in the boiler, also has a green/yellow cable connected to the boiler's earth, in addition to the three identified above. If thats the case, that would sugest that the green/yellow wire is genuinely an earth wire. However we cannot be certain until we have those photos.

Know this needs some more work, but it wont take long once we know… I personally need to be sure about the map of colours on your thermostat. Normally the colour codes would be:

• Brown (Permanent Live)
• Black (Switched Live)
• BLUE (Neutral) - NOT GREY!
• Green/yellow (Earth)

However the electrician who fitted your thermostat strayed away from wiring conventions. We need to be sure before taking another step.

collette

hi

irrespective of what the newlec diagram shows

I have the cables black brown grey and yellow/ green as per the photo can you please provide guidance on my cable wires
photo reattached

Can you please help as I cannot provide any more information thanks

The photo shows my wires this is what I need clarification on where do these 4 wires go?
is it black to NO

Brown to COM

green/yellow to P2

and grey to P1

Thank you

IMG_9120.jpeg

policywonk

@collette Do you have access to your boiler? Can you take the photo we asked for and post it here?

The problem Collette is this: in many homes wiring can sometimes not conform to standards which are supposed to be in place. Your thermostat hasnt been wired using conventional wiring standards. So have to be really careful here, ensure that we, together can safely establish the correct original role of each of those wires. Once we do, it wont take long to determine where they go.

• Please take the photo of the plug identified in Figures 10 and 12 of the boiler's installation guide (my post and link above refers) and we should make progress.
• Also please check on the inside front panel of the thermostat, the wiring diagram should be there. If it is there, please photograph that diagram and post it here.

Had the original electrician followed the colour codes correctly, am sure that the green/yellow wire would represent EARTH.

• The grey wire technically should, if this was wired in in the last 20 years, never represent Neutral - but it seems that it does in this case.
• It is most likely that the black wire is Switched Live and brown is Permanent Live.
• Now if my reading is correct and you are moving the existing wires to a Tado smart thermostat the connections may be:
  • GREY TO P1
  • GREEN/YELLOW TO P2
  • BROWN TO COM
  • BLACK TO NO

However before daring to move those wires we must limit the risk of damage. Please take the photos I've asked for and post them here. Will check twice a day for those photos and help if we can.

Should the burden of taking and posting those photos, or waiting for a response from here is too much for you, do consider arranging local help, perhaps from an electrician to trace the wires for you. Once we know their actual, wire for wire, true original role, we can advise.

Note that we, on this forum, are not Tado employees. We are users of Tado systems who have volunteered to help other users to get things right.