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Last seen: Sep 3, 2026
@jamespa — now that you have done some add on apology, honour is restored.
"done some add on control"??? It's a most elegant solution, might I remind you! Seriously, it is not complicated, and uses the indoor air temperatur...
Thank you! I use plotly in python, with the data coming from csv files. If you are already familiar with python, you will find it a doddle, if you a...
Apologies, I was being lazy, the answers to some of my questions are already in the thread: 9.9kw loss at -2, 10kW heat pump. But the supplementary qu...
As @jamespa says, there is some sort of limitation, or rather imbalance. The difference between the set flow temp and actual flow temp isn't trivial, ...
Which means the actual flow temp will be less than the set flow temp, and it is was probably also the case in the previous image. You need to catch it...
Does that image show a target flow temp of 49°, and a current flow temp of 33°C (the images are rather blurred). If so, and it is not in the deep trou...
I think just a few readings would be useful. Try to pick a time when the OAT is low, and do the same again when it is higher, and you have two points ...
I think that is an important step, to narrow down where the problem lies, even if you need to do it manually. PS didn't mean to rattle off a lot of ...
There are still things that don't stack up in this chart (reproduced to avoid the need for page hopping): Why does the power dro...
Some observations: 1. I for one don't know the Vaillant jargon and that makes it difficult to comment, or even understand what the problem is. I thi...
Yes, but that is in cold weather. If you look at my chart, you will see that I was using around 4kW in the middle of the night (ouch!), but middle of ...
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