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Last seen: Aug 18, 2026
To the final question yes. If the HP is delivering 43 and through to rads its 37, then you are losing about 12-20% in efficiency as a result of the...
If the rads are sized correctly then I would normally say that it could (most probably, but not certainly, is) be an emitter balancing issue. However...
OK, the most interesting thing is the temperature drop across the buffer measured between flow from HP and flow to radiators. I dont think I can see ...
With a very low loss house running at very low flow temperatures its true that the reduction in efficiency from running at the only slightly higher fl...
FWIW my boiler did the same. Sometimes I heard it coming on at 3am in the morning. It heated as well during these forced 'on' periods. But yes, if...
Yuk (comment on the LLH) In this case surely the secondary must be kept running during defrost, otherwise the only water volume available for defros...
Good luck on the modbus. I think you are in with a good chance, these units are based on aircon units used in commercial settings where modbus will l...
... and the value for air changes. Judging by posts on this forum and elsewhere, and comments from a handful of some more independently thinking ins...
Probably not a lot unless you have UFH, although there is a risk of condensation on the pipes When ASHPs are used for cooling one problem that occur...
That seems reasonable if you have a good sized buffer tank between primary and secondary. but not if you have a plate heat exchanger or low loss heade...
I suspect the experience differs a lot from heat pump to heat pump and house to house. When my 7kW Vaillant (no buffer tank or volumiser) defrosts th...
As you say you have to make assumptions about boiler efficiency, probably best based on boiler age and whether it actually condenses or not. Cooking...
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Degrees of Separation
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Readers here please note that Derril Water and many oth...
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RE: Is it the house or the equipment?
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RE: Advice on Vaillant Sensocomfort
Oops, I meant Sensocomfort (the UI to the controls)
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Of course, what do you expect, human beings are human b...
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I'm not sure why you would want to make it more difficu...
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