The Efficient Home Forum

Hi,

I have a bit of a weird detup here which I'd like to bring together over the next few years using evohome. I think, this is probably my only option, but have a few questions.

Firstly, my setup.

Worcester Bosch Greenstar 30CDi Regular Boiler, Hot water cylinder controlled by a Honeywell ST9100A programmer in the airing cupboard and a single zone valve.
Single motorised zone valve to: Wet UFH in the kitchen extension, controlled by a hardwired heatmiser roomstat. (any way of integrating this? What would/could I replace it with)
Single motorised zone valve to: Wet UFH in study, controlled by a very basic hardwired roomstat. (would like to replace this)
Single motorised zone valve controlling the "legacy system" - ie several radiators and towel rails with TRVs upstairs and a Thermaskirt system in the remainder of the downstairs. Controlled by: Honeywell wireless programmer CM927 (the one with the failed LCD screen!) The wirless receiver part is located in the airing cupboard, next to the wiring centre.

Question 1: Can I do a straight swap of the honeywell wireless receiver and programmer for the basic evohome centre to get up and running? (ie the way it's wired?) Appreciate this wont make full use of the evohome functionality.
Question 2: Is it a DT92e that I would need to add in place of the UFH room-stats? Is this hardwired or will I need to wire in a wireless receiver? If so, I believe the cable from the roomstat runs back to the UFH pump,where would I put the receiver?
Question 3: The heatmiser- Can I link this to evohome or do i need to replace with a honeywell product?
Question 4: Anyone ever worked with or connected thermaskirt to an evohome? In theory it should work, but I dont think I will be able to add any smart TRVs to it. I dont intend to add smart TRVs to the system yet, but may for the bedrooms at a later date. My experience is that the thermaskirt struggles to get up to heat in the lounge (where the room controller is usually) but the bedrooms are easily heated by the TRVs.

Thanks in advance for any advice. My main concern is Question number 1!

Hi,
I went ahead and purchased a Connected Home pack and a T87RF2033 Single Zone Thermostat Only (I already have a spare BD91 from my old set-up)

I swapped the old programmer for the evohome controller, as well as swapping the BD91 that came pre-bound. This seems to work fine for running my existing system as 1 Zone. (Although someone elsewhere said this wouldn't / shouldn't work and I would need to start from scratch?)

I had envisaged the sensor in the controller controlling the temperature of my thermaskirt system as 1 zone, then adding the HR92's to my upstairs radiators- however I can see from reading other posts that this may not work?

So- In theory- can I add HR92's to the flow pipes which feed my Thermaskirt, by using a 3/4" to 15mm coupling? (the pipework to 2 out of the 3 is in drywall boxing, so could be hidden, just exposing the valve body and sensors? ) I could then have the Thermaskirt and ALL Radiators controlled by the evohome?

I still need to consider the 2 single zone UFH zones. They each have a honeywell 2 way zone valve. The wiring for room stat at one end simply has 2 wires, which doesn't match ANY of the wiring diagrams I've seen online?


Original POST:

Question 1: Can I do a straight swap of the honeywell wireless receiver and programmer for the basic evohome centre to get up and running? (ie the way it's wired?) Appreciate this wont make full use of the evohome functionality.
Question 2: Is it a DT92e that I would need to add in place of the UFH room-stats? Is this hardwired or will I need to wire in a wireless receiver? If so, I believe the cable from the roomstat runs back to the UFH pump,where would I put the receiver?
Question 3: The heatmiser- Can I link this to evohome or do i need to replace with a honeywell product?
Question 4: Anyone ever worked with or connected thermaskirt to an evohome? In theory it should work, but I dont think I will be able to add any smart TRVs to it. I dont intend to add smart TRVs to the system yet, but may for the bedrooms at a later date. My experience is that the thermaskirt struggles to get up to heat in the lounge (where the room controller is usually) but the bedrooms are easily heated by the TRVs.

Thanks in advance for any advice. My main concern is Question number 1!

You can control 1 zone just with the evohome connected thermostat (if that is what you purchased) and a bdr91. But as soon as you start adding more zones you will indeed need actuators / hr92 / .. controlled by the connected thermostat on all zones.
I suppose you can use HR92 on the flow pipes to the thermaskirt (interesting solution by the way), their location and if they are visually exposed is not really important because you can configure the single-room zone to use a remote temperature sensor such as the connected thermostat's internal sensor or a T87RF. As long as the HR92 are able to connect to the thermostat by rf (not in metal casing etc) and as long as the valve body can provide the necessary flow rate for the heating circuit you should be fine.

Hi Paul,

Do you just have single zone UFH behind these motorised zone valves? If so can be controlled by DT92E or Y87RF (BDR91 controlling UFH motorised zone valve and wireless room thermostat in the room).

As for the legacy stuff, get rid of the motorised zone valve and put HR92's on all radiators and towel radiators. As for the thermaskirt, if you can access the pipework into them and can still ensure sufficient flow rate then you can use something like a V120-15S (https://theevohomeshop.co.uk/radiator-v ... aight.html) on the flow pipe with a HR91 Radiator Controller attached to it with a wireless sensor (T87RF or DTS92E) in the room. We do this same method with kickspace heaters and I have done this here with our commercial high level heaters.

I hope I have interpreted that ok?

Thanks,

Richard