Room Temp Mod settings - Arotherm plus

I’m struggling to understand the control settings on my Valiant Arotherm plus 10kw.

I have an open loop system, one rad circuit upstairs and several underfloor loops down stairs. I have a sensocomfort control and the room temp mod. setting is set to inactive. As I understand it this means that there is no room influence whatsoever and the entire system is run on weather compensation only. In this mode my heat pump cycles on and off regularly throughout the day regardless of what my desired temperature settings or my set back temps are on the sensocomfort (set as time-controlled) - with the heat pump coming on even when sensocomfort reports an indoor temperature above my desired temperature. What I don’t understand then is what is calling the heat pump on and off if there is no room influence and why the heat pump comes on even when the desired room temperature is reached? Any help much appreciated. Thanks

With setting set to inactive, the HP will only follow the heat curve you’ve selected and heat water based on the outside and inside temp

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It only considers desired but not actual indoor temperature in weather compensation mode.

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oops sorry, yes, my bad

Many thanks. If desired indoor temp is say 20 deg and the actual indoor temp is 21 deg, what controls shutting the heat pump off then? Surely it must get a cue from somewhere? In pure weather compensation mode does the heat pump just run continually and bases the flow temp on the heat curve?

Exactly, it completely ignores indoor temperature. If it gets too warm you can lower the compensation curve a bit which I think is detailed in the article linked above.

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If the outside temp is within under the outside threshold setting, the heat pump will start up and shut off based on the internal Energy Integral counter.

Which is explained in my article here

As mentioned above, a target flow temp will be chosen based on your curve and current outside temperature.

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Ok many thanks for this insight, I have read the above, I just cant get my head around it all. Thanks again

Thanks again both. Do you know if there is a way to easy find out how many cycles the heat pump has done in a day, either using the sensocomfort or the valiant control? I feel like my system is still cycling a lot but I don’t have a reference to work form. I see that one of the articles states that less then one per hour is good, is there a rough guide for this?

The valiant app only tells me the total amount of cycles from installation.

As far as I know the only way to check this without any additional hardware would be to write down number of cycles shown in the app and recheck this number after 24 hours. We’re not really in the colsest part if the year yet so some cycling is to be expected even with a properly sized heat pump.

If you have Home Assistant you can install an integration that will automatically fetch some information from the Vaillant cloud that would let you infer whether the heat pump is currently running or not (flow temperature, electrical power).

Most systems will cycle when it’s 10C+ outside.
2 runs an hour is perfectly fine, it’s what they are meant to do.

Mine doesn’t state going steady state until it’s below 6-7C outside… but depends on your heat loss etc.

Can you see how many electrical spikes you’re seeing through your smart meter data perhaps?