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Last seen: May 29, 2025
@jamespa Yes, you are right, I was misreading the diagram. ☹ The main point that I was trying to make, however, is that the heat has to be carr...
@jamespa Apologies. My last post was made before I read your response. The answer is in your own diagram. Resultant internal DT is points 3 to 4 ...
@declan90 Answer is, yes. Power set for a rad is the Flow x DT x SH-of-Water. So if you adjust the flow down, you will have to adjust DT upwards to ...
@jamespa One can only consider the whole system. The DT is a consequence of the emitters connected to the HP. I agree that COP is determined not only ...
@declan90 I have some hopefully interesting input for you if you don’t think it is bollocks. Your statement about adjusting your pump for 5C dT got me...
I was previously under the impression that the Vaillant had a Grundfos UPM2 pump which is an externally cable controlled OEM version but was puzzled b...
@declan90 Thanks for this. I see where you are coming from. I don’t agree that what you are doing by increasing dT will reduce your COP. It’s opposite...
@jamespa Agree entirely.
I have no idea.
The 4kW unit can modulate down to 1.5kW or just below 5 l/min @ 5C dT. However, the flow switch will throw a E911 low flow alarm if you try and go bel...
@jamespa Hi. Information as requested. 1. Samsung Split Gen 4 with Grundfos UPM3 PWM pump integrated in the internal unit with PHE, running for 10...
Apologies for the delay in response due to other heated issues (pardon the pun).😊 Oh boy, why is this so hard? I am not mistaking modulation ...
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