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K3 rads and ASHPs
As part of the recent ASHP installation (discussed in another topic), most of the old K2 (double convector) rads were replaced with K3 (triple convector) rads, to make best use of the limited wall space in a cottage with relatively small rooms. I've noticed a number of them (perhaps all of them at some time or other) don't have the front panel heat up much, if at all, while the rear and middle panels do. This probably isn't helped by the fact K3s appear to be K2s with a third panel welded on in front, so the flow and return connections sit between the rear and mid panel, but I wondered whether this also caused by the relatively low ASHP flow temps, there just isn't enough delta T to get the whole rad hot. The rads are on their own secondary circuit, and the circulating pump Grundfos UPM3 AUTO is currently on its maximum constant pressure setting, and the rads are currently about 80-90% balanced, just got final tweaking to do. Has anyone else had a similar experience, and if so did you manage to improve it? It seems a pity to have all that potential output, but not use one third of it.
Midea 14kW (for now...) ASHP heating both building and DHW
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