Page 1 of 1

Y-Plan Configuration Help

Posted: Mon Jan 01, 2018 8:51 pm
by Westyfield2
Hi,

My plumbing is a Y-Plan configuration with the three-port valve, and wiring is as per page 47 of the installation guide. So I've got two of the BDR91 relays, one from the Connected Thermostat Pack and one from the Hot Water Kit. Radiators are mostly with HR92 valves fitted, though some are running with original TRVs.

When setting it up I know that I went wrong. I got the hot water working correctly and firing the DHW BDR91. I got the 'Others' heating zone working using the Evohome Controller's internal thermometer and firing the HTG BDR91. But when I added the HR92 valves as new zones, the controller wouldn't fire the HTG BDR91 for them - it would only adjust the HR92 radiator valves. The HTG BDR91 would only kick in for the initial 'Others' zone.

So to get it working I told the controller that the HTG BDR91 was a boiler relay. I know this is wrong, but at least it got the HR92 zones to all fire the HTG BDR91 when they needed heat, but also of course the HTG BDR91 activates with the DHW BDR91 too. This was more of a late night desperation move just to get the heating on and I know I've ended up wrong and double bound!

Also when setting it up I couldn't see anything in the configuration that was to do with three way valves. In System Summary my 'Others' heating zone ended up listed as "Zone Valve, Evotouch Sensor" and my 'Stored Hot Water' ended up listed as "Hot Water Only Valve".

That said for having messed up the setup it actually works suprisingly well.

But of course at some point I'm going to start over again, and this time not tell it that I've got a boiler relay.

Is there a definitive set of instructions to follow when configuring it as a Y-Plan system?

I presume that at some point in the setup I need to tell it that the two BDR91 relays are the Heating side and the Hot Water sides of the three way valve? And that a request for heat on any HR92 zone needs the Heating BDR91 plus the relevant HR92 (or just the Heating BDR91 if it's the 'Others' zone from the Evohome Controller's internal thermometer).

Thanks in advance!

Re: Y-Plan Configuration Help

Posted: Tue Jan 02, 2018 11:39 am
by Richard

Re: Y-Plan Configuration Help

Posted: Tue Jan 02, 2018 8:00 pm
by Westyfield2
Thanks - that's spot on what I was after!