How to connect new thermostat to combi boiler (Ed.)

[Mmm1999]

Hi all.

I have a combi boiler in my house and I recently updated the thermostat to a basic Sangamo mechanical stat.

I used 2 cores, permanent live and switch live.

The first night I changed it the heating seemed to come on whilst I was out and I couldn’t turn it off (although the boiler is set to a timer and it wasn’t meant to be on) And ever since then the heating hasn’t been working all all. The hot water seems to be fine.

Has anyone got any idea what could be wrong?

TIA

 

[jj4091]

You need to post your boiler make and model and try the plumbing and heating section.

 

[ChrisJP]

This is the plumbing and heating section!

 

[RandomGrinch]

I recently updated the thermostat to a basic Sangamo mechanical stat

Did the pre-existing stat operate the boiler correctly, and what model was it?
Could we have some photos of your boiler, and how you wired up the new stat?

 

[jj4091]

This is the plumbing and heating section!

It was originally posted in the trade section, been moved by the mods.