Search found 10 matches

by Bluestraw
Thu Nov 03, 2016 7:25 pm
Forum: OpenTherm Setup & Help
Topic: Issue with Vailant Opentherm
Replies: 17
Views: 1079

Re: Issue with Vailant Opentherm

Thanks. Yes it's currently electrically disconnected and latched open (and all my rads have HR92's). Any advice on how to wire up to the pump? My Vailant has an internal pump, not sure how I'd connect the valve appropriately - and my plumber has run far away from my setup as he finds Evohome too ...
by Bluestraw
Wed Nov 02, 2016 5:25 pm
Forum: OpenTherm Setup & Help
Topic: Issue with Vailant Opentherm
Replies: 17
Views: 1079

Re: Issue with Vailant Opentherm

When you use the manual "filling/draining" lever on the valve you are only opening the valve about half way or probably even a bit less than half way. Only the motor can open the valve fully. This will cause a significant restriction in the flow rate through the radiators, and might cause enough of ...
by Bluestraw
Fri Oct 07, 2016 1:14 pm
Forum: OpenTherm Setup & Help
Topic: Issue with Vailant Opentherm
Replies: 17
Views: 1079

Re: Issue with Vailant Opentherm

The boiler flow temp limit should be set to suit hot water recovery, depends on what cylinder you have really? Cylinder is a 300l Joule unvented indirect. Have got the CH valve set open now so things seem better overall. Still seems to stay on (albeit at low temp e.g. 40 deg) during heating times ...
by Bluestraw
Thu Oct 06, 2016 8:37 pm
Forum: OpenTherm Setup & Help
Topic: Issue with Vailant Opentherm
Replies: 17
Views: 1079

Re: Issue with Vailant Opentherm

No idea why, but the post (below) which I submitted earlier isn't showing, so I'm pasting it again! Ahh okay, makes sense. Currently HW target is set at 57 and I have the boiler limit set to 70 - my theory is that 70 is hot enough to heat the HW quickly and just about okay for times of huge heat ...
by Bluestraw
Thu Oct 06, 2016 6:12 pm
Forum: OpenTherm Setup & Help
Topic: Issue with Vailant Opentherm
Replies: 17
Views: 1079

Re: Issue with Vailant Opentherm

Hot water overrun gives the boiler a 'soft landing' when the cylinder is recharged. You may be able to reduce the DHW set point a few degrees. Ahh okay, makes sense. Currently HW target is set at 57 and I have the boiler limit set to 70 - my theory is that 70 is hot enough to heat the HW quickly ...
by Bluestraw
Thu Oct 06, 2016 5:59 pm
Forum: OpenTherm Setup & Help
Topic: Issue with Vailant Opentherm
Replies: 17
Views: 1079

Re: Issue with Vailant Opentherm

Thank you so much for the help. Will do just that. Just two (hopefully final) questions - what difference does it make setting the pump to Comfort vs Eco. I have changed it per your suggestion but not sure exactly what it's done? Also, do I really need the overrun setting for HW since it's got a ...
by Bluestraw
Thu Oct 06, 2016 5:16 pm
Forum: OpenTherm Setup & Help
Topic: Issue with Vailant Opentherm
Replies: 17
Views: 1079

Re: Issue with Vailant Opentherm

Sounds like the boiler is modulating so nothing fundamental wrong but I would bin the heating zone valve and this will let the boiler pump the water round the primary even when there's low load heat demand. The low load operation is a very interesting area and it's best to let the OpenTherm run ...
by Bluestraw
Thu Oct 06, 2016 3:53 pm
Forum: OpenTherm Setup & Help
Topic: Issue with Vailant Opentherm
Replies: 17
Views: 1079

Re: Issue with Vailant Opentherm

Hi You're mixing control strategies here. Evohome does not offer a full integration for priority hot water so I'm not sure what you hope to gain by having an S Plan configuration with an OT bridge. However it is possible to configure this, you'll need to take the feed from C on the DHW BDR to A on ...
by Bluestraw
Mon Oct 03, 2016 8:39 pm
Forum: OpenTherm Setup & Help
Topic: Issue with Vailant Opentherm
Replies: 17
Views: 1079

Issue with Vailant Opentherm

I'd appreciate some help on the following issue I'm experiencing please... My boiler is a Vaillant Ecotec Plus 637 (system boiler), and I have the Opentherm module installed together with the Evohome Opentherm bridge. My installation is 'S plan' and I have HR92's on all radiators, yet I also have ...
by Bluestraw
Mon Oct 03, 2016 8:26 pm
Forum: Honeywell Home evohome
Topic: Installation Guides
Replies: 4
Views: 432

Re: Installation Guides

Same here. I added my order number to my registration but can't send a PM (per the instructions) as I didn't yet 'participate' enough! Would appreciate help to access the customer area.