I see Warm Weather Saver in action. I have one zone demanding 4% and the other 8% but with outdoor temperature of 10C the boiler pump is not running.
Previously it would be in overrun.
I see Warm Weather Saver in action. I have one zone demanding 4% and the other 8% but with outdoor temperature of 10C the boiler pump is not running.
Previously it would be in overrun.
Anyone with an OTGW should be able to confirm this pretty easily. Just check for any OT commands referring to the Outside temperature being passed between the OTB and the boiler. Then just switch the home wifi off and see what the controller does before a Cold Boost zone switches on. Is it able to boost or ignores the boost.
This cold weather boost needs some work.
I have sketched suggestion how I think it should work which would work good if possible, and allow user to calibrate to there house and there individual room if possible.
I definitely need a different SP differential, this morning I was boost and house was warm, very sunny outside but 9'C on evo touch screen. - 12 would be good to start boost at 0.5'C then we should have 2nd differential, lets say -18, then I would want to boost 2'C. The boost should be proportionally scaled between these to set points.
There should be 2 differential's and 2 boost SP's
The Differential SP's should be variable.
The boost SP's should be proportional to differential.
This would be awesome if possible and if could be done by individual room
Attachment 1527
is there an easy way to spot its operating? I've switched off eco mode and immediately the rooms show as needing heat according to the main panel. Is the only way to spot its operational is to monitor the installer menu>boiler demand screen? Im a programmer and data architect and I am not a fan of "hidden features" as users always wonder if the "feature" is really working or not :(Quote:
Originally Posted by kevinsmart
I'm sure the email said there's new icons...
Keep in mind that there is typically a lag - sometimes of a few hours between actual temperature at your location and the temperature reported by most online weather services. I use weather.com data for another project and typically see a lag of 1-3 hours versus my actual outdoor weather station. I also see similar on the evohome reported temperature which typically lags behind significantly.Quote:
Originally Posted by SteveP
It seems that rather than using the temperature forecast earlier in the day for "now", (which would give zero lag but rely on the prediction being accurate) they use the last known temperature measurement which can be a few hours out of date as they don't update in realtime.
So on a day where temperature is rising rapidly you'll see the internet reported figure which is lagging behind being too low, and in the evening during a rapid cool down the internet reported figure will typically be too high.
Another thing to keep in mind is the geographical resolution of different weather services which varies a lot from one service to another. Just because you have your location entered correctly in the TCC portal doesn't mean the weather service Honeywell uses has observation stations near your location. For example I live in Motherwell and while weather.com lets you use Motherwell as a location the data it returns is identical to the data for Glasgow - which is 17 miles away and has quite different temperatures and weather patterns due to the heat island effect. (And probably also affected by the Clyde river)
I don't know which weather service Evohome is using (has anyone figured it out ?) but it may be that you're simply a long way from the nearest weather station that service uses so you're getting weather for a nearby town or an extrapolation from further away weather stations.
In my location the Evohome doesn't do too badly - there is a bit of lag but it's usually within a couple of degrees most of the day so accurate enough for weather compensation. Right now my weather station reports 17.7 degrees - which has risen a degree in the last 30 minutes thanks to clouds finally breaking, and the Evotouch is reporting 15C which it has done for at least the last couple of hours.
No internet weather service will give the same accuracy as an on-site, properly located and installed weather station/sensor, but super high accuracy is not needed for weather compensation.
Are you sure that's new ? Is your system TPI or OpenTherm ?Quote:
Originally Posted by kevinsmart
Because on a TPI system with the default 6 cycles an hour and 1 minute on time the boiler won't fire until there is at least 10% heat demand.
Yep agree with all your observations and that there is a high dependency as to where the local weather station is plus each evohome owners physical location and surrounding. We are protected by hills from northerly winds but this morning we have southerlies so nicely warming up the house :) the issue really is that when you hit the boundary of the cold boost in terms of the actual outside temperature (14.5c) vs the evohome reported outside temp (9C) the difference is enough to be boosting the heating rather than setting it back. That will always be an issue with using internet weather data. Would be useful to know what weather data is being used by evohome as may help identify the accuracy? What may be an option that doesn't involve physically changing the evohome electronics would be to link a DT92 as an outside temp stat and use a zone to record the outside temp until a water proof outside temp stat is available? The DT92 needs to be mounted in a waterproof box but I would gladly give up a zone for better outside temperature compensation as my boiler is a trusty Valliant Combi that I have been told has many more years life and so I wont be able to justify to "the boss" changing the boiler for some time just so I can enjoy opentherm benefits :)Quote:
Originally Posted by DBMandrake
Paul, from the email I can only see cold boost icons having been added :( Warm weather shutdown and load scaling appear to be "behind the scenes magic"Quote:
Originally Posted by paulockenden
Yes, I’m using OpenTherm with my own weather compensation via OTGW and the behaviour has definitely changed with the firmware upgrade.Quote:
Originally Posted by DBMandrake
The boiler was completely off, 10C demand, rather than a low 20-30C demand.