new thermostat

[bigbaddave309]

hi there I have this old thermostat it has a black an brown wire connected with a earth an grey wire not used I'm looking at a new smart thermostat but to my understanding I need constant power would I get this from current set up

 

[RandomGrinch]

my understanding I need constant power would I get this from current set up

That may depend on the connections available at the other end of the cable.
For a simple solution, you could consider something like a battery operated Nest Thermostat E?

 

[CBW]

The earth is only connected to the metal back box, not the thermostat. The grey could be a neutral wire. Plenty of options to choose from as per @RandomGrinch a Nest E could be used, as could any other battery operated thermostat. If the grey is neutral then other thermostats could be used, and depending on your setup/boiler then there are other options too.

What “smart” thermostat were you considering?

 

[bigbaddave309]

The earth is only connected to the metal back box, not the thermostat. The grey could be a neutral wire. Plenty of options to choose from as per @RandomGrinch a Nest E could be used, as could any other battery operated thermostat. If the grey is neutral then other thermostats could be used, and depending on your setup/boiler then there are other options too.

What “smart” thermostat were you considering?

https://www.amazon.co.uk/BECA-Intelligent-Programming-Thermostat-Connection/dp/B0793RM492/ref=asc_df_B078V3V6P4/?tag=googshopuk-21&linkCode=df0&hvadid=309904165679&hvpos=&hvnetw=g&hvrand=6120165053756136264&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9046330&hvtargid=pla-639185303474&th=1

dont no if links aloud but this one

 

[CBW]

https://www.amazon.co.uk/BECA-Intelligent-Programming-Thermostat-Connection/dp/B0793RM492/ref=asc_df_B078V3V6P4/?tag=googshopuk-21&linkCode=df0&hvadid=309904165679&hvpos=&hvnetw=g&hvrand=6120165053756136264&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9046330&hvtargid=pla-639185303474&th=1

dont no if links aloud but this one

So yes, looking at the wiring diagram it needs a permanent live and permanent neutral, depending on your boiler/setup one of those wires might be permanent live, and if you can test the grey, that might be a permanent neutral, so in essence it’s a possibility.

 

[bigbaddave309]

So yes, looking at the wiring diagram it needs a permanent live and permanent neutral, depending on your boiler/setup one of those wires might be permanent live, and if you can test the grey, that might be a permanent neutral, so in essence it’s a possibility.

i have tried to test the wires but getting nothing from black or grey no voltage at all so i dont no if im doing it wrong or not

 

[CBW]

i have tried to test the wires but getting nothing from black or grey no voltage at all so i dont no if im doing it wrong or not

The grey would need to be connected the other end. Black is possibly the switch live. Test between the brown and earth and then switch the thermostat to the in position and test the black.

 

[bigbaddave309]

The grey would need to be connected the other end. Black is possibly the switch live. Test between the brown and earth and then switch the thermostat to the in position and test the black.

I have tried to test the wires but seem to get nothing at all an tried to put thermostat at different positions and get nowt

 

[bigbaddave309]

The grey would need to be connected the other end. Black is possibly the switch live. Test between the brown and earth and then switch the thermostat to the in position and test the black.

i understand i could run a power plug designed for something like this to give it power https://www.amazon.co.uk/gp/product/B09TPJS5MS/ref=ox_sc_saved_title_3?smid=A151HA45N9AR70&psc=1

 

[CBW]

i understand i could run a power plug designed for something like this to give it power https://www.amazon.co.uk/gp/product/B09TPJS5MS/ref=ox_sc_saved_title_3?smid=A151HA45N9AR70&psc=1

It needs a 240vac power supply, not 24v. Does your existing thermostat work? Could also be existing is using 24v switching.

 

[bigbaddave309]

It needs a 240vac power supply, not 24v. Does your existing thermostat work? Could also be existing is using 24v switching.

yes it works but just trying to update it to more modern one

 

[CBW]

Ok, what is your current setup, eg combi boiler?

 

[bigbaddave309]

Ok, what is your current setup, eg combi boiler?

yes combi boiler

 

[CBW]

yes combi boiler

Care to elaborate with a make and model? Might just be better either going for a battery operated one or wireless one.

 

[bigbaddave309]

if it help the boiler is a valliant ecotec pro 28