Honeywell CMT927 wireless Thermostat + Ideal ICOS HE24

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Hi, hoping someone can help. This is a question already answered 7 years ago here ://www.diynot.com/diy/threads/honeywell-cmt927-wireless-thermostat-ideal-icos-he24.185434/ although struggling to reconcile that with the wiring diagrams I have.

As the title says, I have an ideal he24 combi boiler (just moved house, not the boiler I would choose) and want to fit a honeywell cm927.

Below is the he24 wiring diagram
Screenshot_2017-02-03-20-14-37.png


Screenshot_2017-02-03-20-14-47.png


And below is the bdr91 relay box wiring diagram :
DSC_0723.JPG


Surely I want to connect L1 and L2 on the boiler to A and B on the bdr91 (and of course the N/L as per specified)?

Please advise
 
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Out of interest, why is the initial post suggesting that L1 on the boiler is ignored, linking L2 to B, and link L to A on the relay?

At the boiler end connect brown to the L terminal, blue to N and third wire to L2. Remove any link between L1 and L2.

At the BDR91 receiver, connect brown to L, blue to N and third wire to B. Also insert a link between L and A.


The combi boiler diagram C only switches using L2 and ignores L1, just confused with the initial post. It sounds like it worked though just not as per the relay wiring diagram.

Can someone explain it to me?
 
Out of interest, why is the initial post suggesting that L1 on the boiler is ignored, linking L2 to B, and link L to A on the relay?

At the boiler end connect brown to the L terminal, blue to N and third wire to L2. Remove any link between L1 and L2.

At the BDR91 receiver, connect brown to L, blue to N and third wire to B. Also insert a link between L and A.


The combi boiler diagram C only switches using L2 and ignores L1, just confused with the initial post. It sounds like it worked though just not as per the relay wiring diagram.

Can someone explain it to me?
It was Bubbbbbb that posted the thread , have you logged on forgetting to swap user names????
 
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No, I was quoting text from the 7 year old thread written BT stamjammar? Not sure what you mean?

I italicised the quoted text so you could see what I was referring to
 
L1 can be ignored when controls recieve external voltage ie: Sundial plans etc (zone valve end switches).
 
Right - got it I think:

The wiring instructions from the 7 year old post suggested adding the link between L and A (on the relay), so when the relay connects A and B, B provides this power to L2 (on the boiler) and L1 can then be ignored.

Sound correct? It was niggling me I couldn't understand why the advice was to wire it that way, when A and B (on the relay) connecting to L1 and L2 on the boiler seems like the simplest / most logical procedure.

Thank you both for the help.
 
Update :

the boiler end connect brown to the L terminal, blue to N and third wire to L2. Remove any link between L1 and L2.

At the BDR91 receiver, connect brown to L, blue to N and third wire to B. Also insert a link between L and A.

I ended up using this wiring configuration - I opened the boiler and the existing cable only linked to L2. I reused this cable and wired up the relay with the link between L and A, and it all works as expected.

Thanks again for the info / advice.
 

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