Thermostat wiring

[DiyNutJob]

I am changing a room thermostat and need confirmation on the wiring. Thanks.

The top is the existing unit with the earth wire not connected. To the new unit below, I think it should be: blue wire to N, thick-red to L, thin-red to COM. This is right, right?

Do I need to do anything with the earth wire? If not, why is it there?

 

[SUNRAY]

Blue to 'N'
Thick red (actually yellow with red sleeve) to 'NO'
Thin red to 'L' and a link wire fron 'L' to 'COM'
Earth carefully protected to prevent it making contact with anything else, unless of course there is an earth terminal.

 

[DiyNutJob]

The wires from the wall are too short, and I have to extend them. Except, I am no pro and don't have a collection of spare wires laying around. All I have is a short length of blue neutral wire. The wires from the wall are solid core. The extension wires are stranded and wrong colour. Is this a problem, and must I go get some wires of the right colour?

The thermostat is working properly and I am very glad you provided the correct solution. I could have blown up a brand new thermostat!

 

[Deleted member 267285]

Is there not enough play on the cable to pull some through? Looks tight, but doable. It’s not the best practice to use all the same coloured cores.

 

[DiyNutJob]

There's no slack. The thermostat is poorly designed with very well hidden and recessed terminals that longer wires are needed. I understand the best practice. If what I am doing is not against regulations or illegal then I will live with what I have got. It's working perfectly. I don't want to put in extra effort if I don't have to.

 

[EFLImpudence]

All the regulations require is that the conductors are "identified" - letters being an accepted method.

Whats that under the wires?

Not to mention the correct colours to which they are connected.

 

[SUNRAY]

Strickly speaking the wires should be 'identified' but in this case they are so short that I think everyone would understand them.

In my opinion that looks very acceptable.

 

[BlueLoo]

Suggest you might open up the hole in the wall a little to allow those blocks to sit behind the plate and release the potential for tension when closing the unit back up.

Looks tidy enough regardless of regs.

 

[DiyNutJob]

All the regulations require is that the conductors are "identified" - letters being an accepted method.

I have not read the regulations. I was hoping people in the know have the answer without reading. I dabble in a wide range of things. So, there is not enough time to be at depth for everything. But, I know an expert if I saw one

 

[DiyNutJob]

Strickly speaking the wires should be 'identified' but in this case they are so short that I think everyone would understand them.

In my opinion that looks very acceptable.

Good man. I was thinking along the same line. In fact, I could make it a little shorter. The wall wires were short by around 10mm.

 

[DiyNutJob]

Suggest you might open up the hole in the wall a little to allow those blocks to sit behind the plate and release the potential for tension when closing the unit back up.

Looks tidy enough regardless of regs.

If I open up the hole, I will be needing a new wall from all the holes. I have too much on my plate to want to learn wall making. The thermostat maker knew they f'ed up and provided enough room to fit the terminal block within the case.