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Last seen: Aug 13, 2026
Hi… Sorry I was out last night and missed your post. Thanks for confirming you have a rad output of 12000 watts. My calculation method appears to w...
Thanks for your reply... it’s a good sign you’re getting a COP of 4 and operating an open loop system. So my first sentence asked what is the rated o...
Whats the dt50 value of all your radiators? Also, when you observed the cycling how much of your rad system where closed eg. Thermostatic controlled? ...
@walkers-heatpump agree. From a practical point of view your comments make sense…. I guess the key is to check the outside pipes are fully insulated r...
Thanks Derek. Lots of variables to consider. And another reason to try to get the right size heat pump and right size emitter set. Is it also time to ...
Hi Ian, I think you’re mistaking me for the OP...😉 But you’re right the tables produced seem to suit boiler installations rather than the lower fl...
Hi @Linz We have anti freeze valves on our pipes outside. These are usually factory set to bleed at 3degC. This also means we don’t have glycol in o...
Correction : LWT40 should read DT17.5 eg: LWT40 = DT17.5 : 17kw X 0.255 = 4.3KWh
Thanks Derek. That clarifies a lot. It has been very useful to work out the DT ratings of radiators when operating at the lower flow temperatures of a...
hi @derek-m I’ve been looking at your post and recognise what you’re saying and worked out the emitter output for all 7 rads at LWT 50. Can you conf...
Great sketch also of the pipework @riponowl @iancalderbank has great knowledge of your brand of HP so I’ll keep my comments to pipes and rads. As ...
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