Wiser Underfloor Heating Controller - does the relay operate even when a boiler contact hub channel is selected?

[asdsadasdsasdasasd]

Basically my question is as per the subject line.

And reason for asking is that ... well, I tried to drop a wire down from the loft to my boiler, and got my puller stuck ... so no wire, one lost puller, and a blocked riser ... great.

So next idea is to swap out my 1-channel HubR for a 3-channel version, and use the third channel to drive the port/valve that feeds the UFH s-t-r-i-p.

However I also need another valve in the loft, next to the s-t-r-i-p, the other end of the riser. (Because I've got another rad hanging off the same pipe that supplies the UFH s-t-r-i-p.)

So I'm thinking, maybe I can use the UFH s-t-r-i-p's boiler contact relay to operate the valve in the loft.

But that relies on the UFH s-t-r-i-p's boiler relay operating even when I've told it to use the HubR Channel.

I thought I'd ask here in case someone knows. I did search but didn't find anything relevant and I figured it was useful to record the answer.

If I have to go up to the loft with a multimeter to find out myself I will do that and report back. But it's messy and also hot up there today! Easier to ask here. 🙂

[David_SE]

Hi @asdsadasdsasdasasd ,

Thanks for your post.

The relay output of the UFH strip is closing only when the UFH itself has a heat demand. 

If your installation includes iTRV's in addition to the UFH, The relay on the UFH cannot close when only the iTRV's are asking for heat.

If you are using a 3 channel hub, you can assign each channel to UFH and / or iTRV's.

What is the reference of your Wiser Hub ?

Thanks.

BR

David

[asdsadasdsasdasasd]

Thanks David.

What I meant to ask is:

 •  if I have the UFH unit configured to call for heat using a hub channel

 •  will the UFH unit still close its own boiler contact relay?

[asdsadasdsasdasasd · Accepted solution]

I went up with a meter because we had the loft open anyway.

Turns out the boiler contact relay does close, even despite it being configured to call for heat via the hub.

So that's useful to know.

(Posting here in case anyone else needs to know same.)

d.

[David_SE]

Hi @asdsadasdsasdasasd ,

Yes, it will close it but only when the UFH requests a heating demand.

BR

David