Advice on changing an old Honeywell thermostat to a digital

[EddieLJ]

Hi all.

I would like to change my old analogue honeywell for something i can programme however i'm at a complete loss how to do this. My old thermostat has a four wire connection (see pic) and the new thermostat i'm considering appears to have a three wire configuration

https://www.screwfix.com/p/honeywell-dt90e-digital-room-thermostat-eco/41365

Could anyone advise please, many thanks.

 

[muggles]

You can't program a DT90, it's just a thermostat. You need something like a T4 if you want a programmable stat.

The four wires you have currently are Live, Neutral, Earth, and Switch Live

 

[EddieLJ]

Thanks muggles, in my haste i have linked the wrong thermostat, I actually had two in mind but am leaning towards this one
https://www.screwfix.com/p/horstman...at/12157#product_additional_details_container

But if i went for the T4 as you suggest how would i wire it up. My heating system is a combi boiler btw. Many thanks.