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Last seen: Nov 12, 2026
OK, so 41.9 in from heat pump, 37.1 out to rads, drop of 5C = 10-15% efficiency penalty. Not sure how the return to the heat pump is higher than the ...
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...
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Degrees of Separation
Latest Posts
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@batpred The Daikin temperature probe protrudes from th...
By Toodles , 20 minutes ago
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RE: Air source heat pump roll call – what heat pump brand and model do you have?
@editor And as an occasional contributor, may I say wel...
By Toodles , 2 hours ago
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RE: Should Households Who Can Afford It Pay More for Energy to Help Those Who Can't?
They don't have to try. Our entire system is d...
By EtchedPixels , 3 hours ago
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RE: Why don't people choose heat pumps?
Fair enough. I guess I was thinking of pipes that run ...
By JamesPa , 3 hours ago
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RE: How Can I Prove Coal Was My Main Heating Source Without Receipts?
Got excepted for the grant now so thanks for the replie...
By Chilli304 , 7 hours ago
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Daikin Altherma 3 R F+W, room thermostat control, weath...
By JanHarley , 8 hours ago
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RE: Buffer tank on a 2 x 14kw Ecodan system
Pretty much as I had guessed in my crude scaling from m...
By JamesPa , 11 hours ago
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RE: Help me keep the faith with my air source heat pump installation
Well you have a vibration generator running at some fre...
By bobflux , 1 day ago
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RE: Who's your electricity provider and what's your tariff?
@downfield Thats a decent rate, I’m shocked they hadn...
By Papahuhu , 2 days ago
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RE: Adventures in heat loss calculations
@toodles thanks! So as suspected, around a doubling of ...
By SusannaSaunders , 2 days ago
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Six books in three years and I think I’ve now covered j...
By Mars , 2 days ago
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RE: Grant Aerona3 13kw - Buffer Tank - Heating Journey
@heymikey Well done in achieving as nearer a match acro...
By Toodles , 2 days ago
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Grant Aerona - Weather Compensation and Schedules
Im trying to set up a friends Grant Aerona. The WC curv...
By bontwoody , 3 days ago
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