The Efficient Home Forum

Hi,
I recently got a new system boiler fitted as follow:

1 - Greenstar 30CDi Classic System Boiler Erp
2 - Worcester single coil indirect unvented hot water cylinder

I purchases the following for hot water and heating
https://theevohomeshop.co.uk/en/honeywe ... ack-a.html

I have been trying to reverse engineer the current wiring with one of the figures in the guide. The closest match to the wiring I have got is S Plan:2 two-port valves with a wired boiler on page 46. Would that be reasonable assumption to make?

Below are the pictures of the system I have.
https://onedrive.live.com/?cid=375254bd ... 6i3eOGybAQ

I will carry on with the reverse engineering of the wires and post here before I do them. I have high hopes as I have heard excellent feedback about richard who can help me with this.

Regards
Azhar

Am i correct to assume after all is setup, I would not need the room stat and programmer as this will all be controlled through Evohome for hot water and heating?

Hi Azhar,

I assume this is S Plan from the wires coming from the valves (Page 42 figure 2 evohome Installation Guide)? Just follow the wiring diagram on page 46 but follow my wiring for the unvented cylinder to maintain G3 regs (https://theevohomeshop.co.uk/forum/view ... f=15&t=176).

If in doubt, get an installer.

Thanks,

Richard

Hi Richard
Thx for quick reply. I have managed to reverse engineer most of it apart from wires from the boiler.
In the diagram on page 46 it only shows 3 wires but my boiler has 5 wires which are connected on the junction box. Any reason for that?

The Worcester boilers can be wired a couple of ways and you end up with 4 or 5 wires depending on how this is. I can't comment much more than this, but there is a Worcester wiring guide which will help (https://www.worcester-bosch.co.uk/files ... ller_3.pdf) look at page 17.

Thanks Richard.

Your comments were enough to get started. My friend is electrician and he managed to do all the connections according to diagram and removed the old thermostat and timer. He did not had any experience is setting up rest of the stuff and left it for me which is fine. It all connects on the evohome controller aswell and I can turn heating on / off with the controller. Next would be to start adding HR92 to radiators and create zones.

Only question is, although my heating BDR is working perfectly fine, hot water BDR starts giving COMMS Fault after few hours of usage. It has happened so far 2 times and only way for me to get rid of the error is do full factory reset and re-bind all BDR's

I have checked the RF strength of them as well and it comes back as excellent. Although when i send the signal test red light on both of the BDR's flash instead of the one i requested. Is that normal?

Yep normal for them both to flash. Any images of the BDR91's as it sounds like they are installed too close to each other or something metallic...