Evohome installation help

As already said you seem to be struggling with this, here is a wiring diagram to see if that helps if not I suggest you throw the towel in, the central heating zone valves can just be hooked open permanently and you need to remove the 24v link on the pcb.

the two red dots on the diagram show where you have to run a wire through the unvented stat (to comply with g3 regs) and a disclaimer the diagram is the way I would wire it up but I am not working on your heating system so it may not suit, the responability is yours.

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thank you for this - will see what i can do ;)
I was going to lock open the CH Valves but was told that in doing so will only half open them, is this correct?
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As said, simple enough task. Am little astonished heating engineer on site is missing elementary stuff like S plan wiring. While Evohome installation may not be straightforward, zone wiring should not be rocket science to a spark or a heating engineer.

At the end of the day what is a zone valve or a BDR- a glorified relay that a spark should not have any trouble using, be it with a little prodding that has already been carried out above. Call me a dickhead or what you will OP, clearly as a spark you are letting your side down. No humbleness either or grace to thank those that are helping you:whistle:

I am not going to argue or be critic but i just want to clear something up - i am NOT an electrician, when i left School i started out as a laborer and ended up working for a builder for 7 years, i got C&G in general home electricity services, i later (and regrettable) left the trade and i have been an (IT) Cisco Solutions Architect and Enterprise IT Project Manager. However i did pass my Part P 5 years ago when i moved into this house to complete the re-wire myself and not done anything major since.

I am a very hands on person and i get a great sense of pride and satisfaction for completing work myself - Criticise me as much as you like for this but please remember this is DIY forums, Do It Yourself.

I cant thank you all (you included) enough for the help you have provided to me.
Hello again,
Day off yesterday as it my youngest's 8th birthday.

Had a few hours spare today so ive wired it all up again and installed 10 HR92's.

Hot water seems to be working spot on, when in schedule it calls for heat and it all kicks in fine and hot water thunders through, albeit an awful lot hotter than when using my Vailalint controls, i guess that is modulation for you , what i have found with this though... once it hits target temp the valve doesn't shut off and my boiler continues running, why would this be?

More importantly and most annoying is my controller talking to my HR92's, this has a total mind of its own, sometimes its slow others its none existent, i have 5 HRs on my test bench with nothing around them all 50 CM apart and my controller next to them, then i have the other bunch fitted to rads.

1) I go to the RAD and manually turn the HR head and i can hear the motor open and i get instant heat flow, 6 seconds later my controller will update and show the new change.
2) from my controller i go to the zone and cancel override and/or change the heat setting and this does NOT report back to the HR - the ODD occasion maybe 1 out of 10 attempts it will do .
3) From the HR head if i change the temp setting a degree another 6-8 seconds and the temp on my controller changes but FROM the temp on the head not the controller.

It seems a one way street here.

From my phone app if i change settings it also does not seem to report this on the controller yet sees my zone data.

Now, if i go to the RF Comms Check and run a scan for the Heat demand it comes back Good, for Hot Water it comes back Excellent AND then if i test each of my HR's i get Not Received - is this normal? BUT then if i hold the button in on my HR and set it to "Binding" i get a response as Excellent.

I am beginning to have doubts on my £1100 investment now.

Can you help me please?
furthermore, i have just been testing some more, i set all my RAD's to 25C, waited 15 mins, went to check and they had all updated from my controller, went to my zone valves and locked open the downstairs and it worked, one thing i noticed at the same time is the DHW valve was also open and water was passing through, or so it felt. I will double check the wiring of this tomoz but for now i have powered it all down again. Before i did that i went into my loft and checked the BDR, it was green and my boiler was happily doing its thing, i set my controller to "heating off" and after 10 minutes there BDR was still green.
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Post a diagram of how you have wired the system and did you remove the 24v link?
my wiring.jpg
Here it is, i have not wired in my two CH Zone Valves at this point for testing purposes, they are locked open manually with lever switch, once i get the system working as it should then i will take brown (live) from both CH ZV back to my CH BDR "B" / 4 UNLESS my wife says she would like the two towel rads heated whenever there is a DHW demand then i can leave them in manual switch OR i guess i could have UPstairs ZV wired back to 8 and Down back to 4 - Unless i have it all wrong?
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How is the dhw zone valve turning the boiler on ? do you have the grey and orange connected, ? your diagram shows you have a permanent live from 1 on the block connected to the switched live to rt on the boiler , is your diagram correct ?
How is the dhw zone valve turning the boiler on ? do you have the grey and orange connected, ? your diagram shows you have a permanent live from 1 on the block connected to the switched live to rt on the boiler , is your diagram correct ?
Well spotted, No not correct, i have amended that now.

So the grey and oranges are NOT in use.

There is no link from DHW BDR to boiler, it was my understanding that the signal is sent from the Controller to the Boiler BDR to switch boiler "on"
No both the bdrs need to be connected by a wire to turn the boiler on, you can use the grey (connected to permanent live) and the orange connected to rt on the boiler or connect to 8 and rt in the boiler.
So like this?

My boiler has an LCD screen with menu no dials, Hotwater tap has gone off already and just the Rad icon and option to change Target temp only.
Once i get the wiring correct - do you have any thoughts on why there is such delay and lack of response in my controller / HR connection.
Sounds like they aren't bound correctly. Did you follow my advice to ensure you wait at least a minute between binding each item?
Sounds like they aren't bound correctly. Did you follow my advice to ensure you wait at least a minute between binding each item?
Yes, all are bound correctly.

i have just spoken to resideo tech support and i have my wiring correct, there is no need for an orange ZV cavble the BDR is the orange cable.
DHW calls for heat BDR kicks in sends power through my HL Stat and then to the BROWN of my ZV opening it. the controller then sends a command to the Boiler BDR/Relay turning the boiler on and thus sending heat.

Tech also told me that the HRs go to sleep for 3mins 59 seconds so this is why there is a delay in getting data back from the controller, when i locally override the HR that wakes them up and sends the data and then goes back to sleep, when the system is set to "off" it has to wait for ALL HR92's to come back as off before the demand for heat is turned off.

I am going to test it all again now and i will put my multi meter on my DHW valve to see if it is actually open or closed
So you have to configure the controller to energise both bdrs at the same time to get hot water ? have you changed the wiring from post number 38 ?

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