Do you mean its set lower?.. During the day the room stat doesn't do anything as it's set above the highest temp that the room gets to (20 deg).
Do you mean its set lower?.. During the day the room stat doesn't do anything as it's set above the highest temp that the room gets to (20 deg).
No, it's set to 23 during the day, the room temp hovers around 20-21, so doesn't activate. At night it's set to 18, so again didn't activate as room temp is higher than that. I'm talking about the controller, and not the boiler, that is set to 20.Do you mean its set lower?.
It's just digital, ON when room temp is below 23, and OFF (at night) when above 18. So WC has full control. ie. I'm letting the WC set the room temp for me (20/21). It rarely reaches the set point (23), unless cooking or something, then it will turn the boiler off until it drops below 23. I just move it to a cooler room then, so the other rooms don't get cold. I don't want the boiler to be switching on and off during the day, hence the high set point. Did that make sense? I don't mind the questions.What exactly is the controller doing when its set to 23C, ie what is the controller output doing, is it a analogue output or digital, ie on/off.
This makes sense "At night it's set to 18, so again didn't activate as room temp is higher than that. I'm talking about the controller, and not the boiler, that is set to 20." but the day setting doesn't, it would, (to me) make sense if the room temp hovers around 23C and its setting was 21/22C?.
It doesn,t really because you say "At night it's set to 18, so again didn't activate as room temp is higher than that." which makes perfect sense as the room temperature would need to fall to < 18C to start the boiler, acting like any roomstat, but if its set to 23C and the room temp (during the day) is only 21/22 then it will activate and keep the boiler running until the room temperature reaches 23C?. You can't have it both ways, if the measured value is higher than the SP then boiler OFF, if the measured value is lower than the SP then boiler ON, if you have it set to 23C during the day then the room temperature must be higher than 23C if you don't want the boiler to come on, but once the temperature falls below 23C then it will fire up the boiler? but you say the room temperature hovers around 21/22C and the boiler still stays OFF even though the SP is 23C?It's just digital, ON when room temp is below 23, and OFF (at night) when above 18. So WC has full control. ie. I'm letting the WC set the room temp for me (20/21). It rarely reaches the set point (23), unless cooking or something, then it will turn the boiler off until it drops below 23. I just move it to a cooler room then, so the other rooms don't get cold. I don't want the boiler to be switching on and off during the day, hence the high set point. Did that make sense? I don't mind the questions.
Well it would if the controller was in charge, but the WC is now controlling the boiler between those temperatures, as I said the controller's sole purpose is to switch the boiler on and off according to the temperature I have set for it. yes the boiler is running, but only to heat the house according to the heating curve, that's the general idea of WC is to keep the temperature steady. Boiler pump is on, but burner is modulating according to the flow temperature, sometimes burner is off, other time modulating at around 10%.but if its set to 23C and the room temp (during the day) is only 21/22 then it will activate and keep the boiler running until the room temperature reaches 23?
Are there any trends out there showing the "room" temperature plotted against the OT temperature from people who are happy (apart from you?) with WC only control , NO roomstat.
Sorry, not sure I understand, I may be explaining things wrong. The house is hovering around that because the WC is controlling it totally. I don't want the boiler to switch off and on around 20 C, that would sort of defeat the object of WC which is to maintain a steady temperature.Yes but if the house is hovering around 21/22C, which I assume you are happy with during the day, why do you want the boiler to be enabled/firing, it doesn't really matter what the WC is doing except that its setting the boiler target flow temperature so low that the actual boiler temperature is greater than that, in which case it will not fire, until the WC (say as the evening moves on) raises the boiler target temperature.
Why don't you set the controller to say 20C?.
Hi JohnRead thread with interest as I've just had a Viessmann 050-w 30KW combi installed. I'm considering WC and as i understand it from the supplied manual, you can have an on/off stat connected too (not opentherm). So as @tech749 describes, this external hookup can be used to override what WC is trying to achieve by switching CH on or off based on a limiting indoor temperature.
I was wondering - do you need on/off stat because this boiler has only 'Standard WC" controls?
Reading this WC PDF from Viessmann, it seems to suggest Night Set-back is only available with 'Advanced WC' Can anyone with an 050 confirm. I've not been able to find a thread or video of anyone showing WC options on this boiler. If it isn't available, i can understand why you're using the on/off stat, and just considering if i'd do same. ta
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