accuracy of measuring instruments
Hello AC (and others),
I'm only up to page 55, so it might come up later on, but I thought just to give you a hint.
You're talking about very different (calculated) COP's in further identical conditions.
Since the temperature difference between heating water in/out of the condensor is realtively small, it's very important to have very accurate temperature measuring devices at those places.
In my air/water heatpump installation (Mitsubishi Zubadan) I have a proffesional thermal energy meter (Kamstrup). I know in the factory they pair the tempearture sensors (in/out), so that they have sensors with very similar deviations.
Suppose you have a sensor with an accuracy of +/- 5% + 1 digit and both temperature sensors measure tempeartures only differing 5°C.
If one sensor is measuring 1°C too much and the other one is measuring 1°C too low, you could read a temperature difference of 3°C where the real value is 5°C. In that case you have a misreading of 40% !!
And then you have the others inaccuracies, like waterflow etc.
The only thing I want to say is: don't just take the values you read for being true. Take care with interpretation of measuring data.
Maybe you know all this, I would just avoid you draw the wrong conclusions.
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