The Efficient Home Forum

Posted: **Mon Nov 08, 2021 2:05 pm**

Hi,

I had evohome installed in 2015 and it the evohome controller was the ATF200UK.
I would like to upgrade to the new one (THR99C3110).

It seems to come with a new wireless relay. Can anyone provide instructions on how to replace the old kit with the new one?
Or perhaps this is provided in the instructions. Have yet to purchase one but will when I'm clear on installation process,

Thanks in advance,

John

Posted: **Tue Nov 09, 2021 8:32 am**

Hi John,

OK, firstly lets not be lining Amazon's pockets when your on an independent, family run shop's forum asking questions hey?

The non-Amazon part code is ATP921R3100 and available to buy here (https://theevohomeshop.co.uk/honeywell- ... 73547.html).

The new evohome installation guide is available to download here (https://thesmartthermostatshop.co.uk/in ... tachment=7).

Its easy enough to do, just takes a bit of time to do correctly.

Posted: **Wed Nov 10, 2021 9:45 am**

Great. Thanks for the info!

The Efficient Home Forum

Replace old ATF200 with Honeywell Home THR99C3110

Replace old ATF200 with Honeywell Home THR99C3110

Re: Replace old ATF200 with Honeywell Home THR99C3110

Re: Replace old ATF200 with Honeywell Home THR99C3110