room thermostat wiring

[pacer property]

probably a simple one but can anyone shed some light on the wiring from old to new room thermostats that the pictures show. i want to use the Esi one to replace the old if possible.

 

[stem]

Unfortunately, the photo's don't help much. Several Danfoss thermostats look the same but there are several variants, some are 24v some are 230v. Also, some heating installations use two wires, some three, so, if you could post details of the model, a photograph or details of what wires are presently connected to where inside would be helpful.

Same for the ESI thermostat, so again, information about the wiring terminals and what they are called from the installation instructions would help.

 

[pacer property]

thanks for the help. pictures taken with covers off. boiler is a Worcester 28i Junior if that makes any difference to any thing.

 

[stem]

OK, you don't state the model of the Danfoss to enable me to confirm what the terminal numbers refer to, but it would appear to be presently wired as:

Terminal N= Neutral
Terminal L= Live
Terminal 2= Com (linked to live)
Terminal 3= On (Switched live)

If the white object labelled RTP shows the new thermostat connections, then you would just need to use the wires presently going to the Danfoss terminal 'L' and terminal '3'

Danfoss 'L' = New thermostat 'L'
Danfoss '3' = New thermostat 'on'

You can dispose of the link, and you don't need the neutral or the earth, so they should be isolated safely and tucked out of the way.

 

[pacer property]

just to clarify then, this is the danfoss model label and the british gas timer model label

 

[stem]

Thanks, terminals 2 and 3 on the Danfoss do correspond with 'Com' and 'On' so my previous post was correct.

 

[pacer property]

bit of confusion now on my part as the right hand is the original timer and the left is the stat. i have removed both from wall and the wiring doesnt seem to correspond. can you tell me as from the right hand part of the pic as this is the main in. cheers

 

[stem]

The thermostat is the item that you said you wanted to swap over, so that's what I've described for you. To do this, leave the timeswitch wiring alone and make the changes at the thermostat backplane wiring.

1. Black wire presently in the thermostat N is not required isolate it safely.

2. Discard the brown loop of wire

3. The remaining brown wire presently in L at the thermostat goes to 'L / Com' at the new thermostat.

4. The wire presently in terminal 3 goes to 'On / NO' on the new thermostat

5. The earth is not required isolate it safely.

Or..... is the new thermostat actually a programmable thermostat and you also want to remove the old timeswitch as well? If so, 'that's something else altogether.

If you do want to get rid of both, then I reckon my sketch below is how it's wired now. (earths omitted for clarity) But please check to make sure. Terminal 4 isn't shown as being used for anything by the existing programmer, so it appears to have just been used to connect the two grey wires together.

And if the above is correct, this is how it would be after swapping over, with the wiring to the existing thermostat completely removed.

 

[stem]

You've gone a bit quiet, pacer property, did the diagrams help?

 

[pacer property]

thanks for all your help. finally got round to doing it. such an old house that the wiring is confusing to say the least. But done now and seems to be working fine, customer happy. cheers!!