Worcester 24i RSF combi connecting to a Honeywell Cm921

[rd350ypvs]

Morning everyone.

I have just purchased the above wireless controller and after looking at the connections was just wondering if my wiring is correct.

On the boiler I have removed the original Mechanical timer and replaced wire link.

Using X2 terminals CN, CI, CL
I have connected
CN - Not conected
CI ----->B
CL------>A

Do I need a wire link between L & A ?
Do i need a wire link between L & L in relay panel ? The reason being that I have placed the live from the boiler into the L terminal directly next to the N terminal, does it need to go into the far L terminal ?


Thank you and hope I can get this working.

 

[stem]

The Honeywell needs a Neutral supply, which you don't mention (other than not connected). It also needs a Live supply and a Switched Live connection to control the boiler. As the Worcester 24i RSF uses 230v switching, you will also need the link. Here's a drawing. The two L terminals in the programmer relay box are already connected internally.

Untitled

• stem
• 29 Jan 2013
• 1

 

[rd350ypvs]

Cheers for that Stem, What I probably forgot to say was that I have the receiver powered directly from the boilers 240V supply terminals L & N and not from treminals CN, CL, would this matter ? APart from that I am only missing the link between L & A


Cheers



Andy

 

[stem]

OK. It's not the usual way, as it's normally easier to run one 3 core, than two x 2 core cables.

So as you have a separate N & L supply from the boiler, and have run two separate live wires to 'L' & 'A', you don't need the link, and what you originally stated is OK.

CI ----->B
CL------>A

Untitled

• stem
• 29 Jan 2013
• 1

 

[rd350ypvs]

Cheers Stem, thats what I have as connected. will post back here if any problems


Andy

 

[rd350ypvs]

Well it looks like I could have a faulty Cm921 since it is acting weird. Is there a way to truly hard reset it since removing the batteries doesn't work and User settings is stuck on '1' and you cant change it, so the following problem occurs

The display is stuck on showing TARGET TEMP, nothing works to change this from the display. Pressing the temp up down buttons changes the temp as per instructions but if you press the 'i' button it should alternate between room temp and target temp but it just stays on Target Temp


Any ideas to get this thing to talk to the BRD91 properly ???



Cheers




Andy

 

[stem]

See "Fine Tuning the CM921"

Item C ii) on page 11 of the manual

 

[rd350ypvs]

Tried all that Stem, about 50 bloody times lol, will get it exchanged. Re-binding didnt help either, all communication seemed fine, just the CM921 unit is stuck on TARGET TEMP and refuses to show room temp at all

 

[rd350ypvs]

replaced with a new unit and now all is well, works like a champ