Drayton L111 switch and Drayton RTS 3/4

[Dec2203]

Hi,

I had issues over the past couple of days with swapping the above for a TADO room stat tried two lots of wiring diagrams from TADO and thought it was working however heating was radomly on or off couldnt work it out and customer services not helpfull so sending back hoping to go to the Hive we have nest in our holiday home. but looks like hive could just go in in replace of the room stat i might be wrong.

I was considering leaving it to our boiler service guy but if it was just a matter of swapping the wires over im fairly happy to have another go. However i would like to see where i went wrong the tado in the end i put where the roomstat was following their wiring diagram attached all orgininally i was going to take timeswitch out however i seemed to have an extra wire on terminal 4 on the l111 which wasnt on the intstrutions for that ive attached all pics bellow of the setup. the boiler is a Glowworm Ultracon 30 cxi

I just want an understanding of where i went wrong and if hive is the better bet i would prefer to be able to just replace the room stat so i can put the old one back on if we ever move.

 

[stem]

From the diagram below, you can see that terminal 4 of the LP 111 is a spare, it is not connected to the internal workings of the timeswitch and so it has just been conveniently used by the installer simply as a means of connecting the two black wires together. [BTW the PDF you have labelled L111 instructions is actually the Tado manual]

And according to the manual the Hive connections (single channel version) are exactly the same & terminal 4 of the Hive isn't used either. Personally I would have put both black wires in a separate connector. Otherwise, as it did in your case it can cause confusion.

The old room thermostat needs to be decommissioned it can't just be disconnected otherwise the wiring will be open circuit and not operate.

Find the other end of the thermostat cable to that shown in your photo above. It appears to go to the LP111. When you find it, note carefully where the brown and black wires are connected. Now disconnect all of the wires and remove the cable and old thermostat. Now insert a link to join together the two terminals that you have just removed the brown and black wires from so that they are electrically connected.

The process is reversed should you want to reinstall the old thermostat. That's the professional way to do it, but if you don't mind a bit of a bodge and you prefer to leave the old thermostat in situ you can do but move the black wire from terminal 3 and put it in 1 along with the brown loop already there. That will take it out of operation and complete the circuit.

I'm guessing with the Tado that perhaps you didn't do this, and both the Tado and the old thermostat were both trying to control the heating, and resulting in the random operation of the heating you describe. But unless you tell us exactly what you did we can only guess. Not that it matters now anyway, you know what needs to be done to install the Hive.

 

[Dec2203]

Brilliant that makes abit more sense i basically left the time switch in situ and put wires from the room stat into tado grey cable went to p1 which is apparently unused L - com 3- NO and earth is to blank on the tado.