Hi @Bramco
You’re right about all the things you say. It is physically impossible and it is a result of the system measuring things with a bit of a delay.
As you say, I’m getting the values from the vendor’s system so can’t alter how that works. Notably it’s a bog standard MMSP system so you’ll see lots of people with behaviours like this as heat pumps get fitted in more properties.
There is another slightly unusual situation that is occurring as I type this. When the hot water is finished it’s hot and I pump that round the radiators which gives me some space heating in the way this vendor’s system measures it. That gives insanely an high instantaneous CoP because it’s just pump electricity being used. I’ve described it with examples in this post.
I’m not troubled by it because I tend to look at the CoP over the time of an event rather than the instantaneous CoP. That’s partly why I want this type of application in Emoncms, it allows you to look at the experiment’s outcome more easily by reviewing what makes sense to the experimenter.
BTW I should mention that Emoncms’ ability to return data “at intervals” is incredibly useful. My home-grown web-app tries to load all the data from every minute since October. As time goes by it’s getting harder and harder to do that. Of course Emoncms using PHPFINA can show an “all time” view relatively easily which is rather wonderful.