Best evohome setup for rads & single UHF ZONE

All Honeywell Home evohome general discussion in here! *PLEASE NOTE* Official Resideo technical support is on 0300 130 1299.
Post Reply
Philayre
Posts: 3
Joined: Wed Jan 26, 2022 8:42 pm

Best evohome setup for rads & single UHF ZONE

Post by Philayre »

Hi guys, I'm currently in the planning stage of converting my existing combi boiler setup to evohome!!

Currently I have:
* A combi boiler in an s plan system with two zone valves.
* One zone valve is connected to all radiators in the house
* The other zone valve is connected to the UFH (single room)
* The zone valves trigger the boiler.

I understand this isn't an ideal position to start from.

My plan is to:
* Add HR92 valves to all rads
* Remove the zone valve supplying the radiators
* Remove the link from both zone valves to the boiler
* Add a BDR91 to the boiler, as a boiler relay
* Add a second BDR91 to the UHF zone valve
* install a wireless stat in the room with UFH.

Have I got that right?

I suppose, alternatively I could:
* Leave the UHF system as it is, with the zone valve firing the boiler
* connect a BDR91 to the radiator zone valve, configured as a boiler relay
* add HR91 valves to the rads...

I suppose this second option isn't ideal as it leaves the UFH system out of the evohome controller, but it would save me a lot of rewiring!

Any thoughts?
Philayre
Posts: 3
Joined: Wed Jan 26, 2022 8:42 pm

Re: Best evohome setup for rads & single UHF ZONE

Post by Philayre »

Apologies, I see this topic has been raised before.

I found the answer given here very useful:

viewtopic.php?f=4&t=4309

Thanks!!
User avatar
Richard
Site Admin
Posts: 1199
Joined: Fri Jun 10, 2016 4:08 pm
Location: Mid Wales
Contact:

Re: Best evohome setup for rads & single UHF ZONE

Post by Richard »

Philayre wrote:My plan is to:
* Add HR92 valves to all rads
* Remove the zone valve supplying the radiators
* Remove the link from both zone valves to the boiler
* Add a BDR91 to the boiler, as a boiler relay
* Add a second BDR91 to the UHF zone valve
* install a wireless stat in the room with UFH.

Have I got that right?
Yep sounds spot on... Use a Y87RF or DT92E for the single UFH Zone as buying them separately won't be cost effective. Also you will need HR91's unless you can find some somewhere else online (these will be old stock though). 8-)
Home: 2012 Built Oak & Timber Frame Home (EPC Score 95 - A Rated)
Renewable Tech: GSHP, Solar Thermal, Solar PV & 20kWh Battery Storage
Smart Home Platform: Home Assistant, Shelly & Salus Smart Home
Post Reply