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Stiebel Eltron Servicewelt COP figures compared with OpenEnergyMonitor
We have a Stiebel Eltron WPL25 ASHP with access to lots of data via their Servicewelt portal. This includes data on heat produced, power consumption and COP. This data is created using a proprietary algorithm. I'm trying to get a figure for percentage uncertainty for this data, but so far SE are unable to provide this. They say that their data is a guide. Question: has anyone fitted OpenEnergyMonitor level 3 (with heat meter) to a SE heat pump and compared actual measurements with the data SE provide?
@shaeney are you running OpenEnergyMonitor?
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I also have the WPL25.
I find the Steibel Eltron Portal very, very basic.
So I also run a Home Assistance Green Pi, which gives me far better information and graphs/visuals. However, its integrated with the SE data via CanBus. So its their data, as opposed to a separate monitor.
I do have a SunSynk inverter with a CT clamp on the entire supply, so I can kinda see whats happening at a higher level too.
So today so far, total consumed is 40KWH
EV took 20KWH
Battery charge took 12KWH
Heat Pump is reporting 3 KWH on Hot Water and 4KWH on Heating.
So I think it's there, or there abouts correct.
Hope this helps!
@shaeney thank you. SE have 2 portals. The standard offer is very basic - connects to the WPM (HP manager/controller), but the online portal is much more comprehensive: https://servicewelt.stiebel-eltron.de/ You need an account and have access to everything as far as I can see. You can select parameters and graph over periods of time. You need to call them to get access.
I have billing quality meter on the compressor supply, and a CT clamp on the controls/pumps supply. If I compare the kWh used between this meter and what SE is recording for the compressor via the portal, I am getting 7% difference - actual use is 7% higher than SE is presenting.
The problem is that I have no way of measuring the actual heat produced (I don't have OpenEnergyMonitor) - so I have no way of working out the margin of error for the heat produced data provided by SE (ie, is this also 7%?). So I can't assign a margin of error figure to my COP calculations.
I am preparing a presentation for a village meeting on heat pumps and I want to be as rigorous as possible with my data. This is the video we created for our project which is to encourage retrofitting: https://www.youtube.com/watch?v=Ucf0-L8y9Q0
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