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Last seen: Aug 25, 2026
I can certainly agree with that. I reckon that there are a fair few PhDs in 'optimised' control of heat pump central heating systems under various se...
Even a lossless PHE will reduce the system efficiency because the flow on the CH side is necessarily colder than the flow on the CH side and thus the ...
You are mixing up cause and effect. The heat delivered by the heat pump to the system absolutely is equal to (mass) flow rate * specific heat capacit...
@cathoderay Reading the above I think there is a large measure of agreement that the difference in operating conditions vs the oil boiler, and ...
One further comment occurs. We know that cycling is bad news, but we cant quantify how much effect this has when the unit is below minimum output. ...
When I asked the question I was thinking secondary. A 3 bed house may be quite a lot smaller than the designers of a 14kW unit were thinking. I have...
@cathoderay My simple view is this: They have losses, so they increase the flow temp required at the ASHP to achieve a given flow temp at the emitter...
Frist reactions (more considered ones later...) Indeed so. Cycling is said to be ruinous to efficiency but I have never seen the extent to w...
As I indicated in my previous post, I simply don't believe this. I think its an apparent/real SCOP problem not house needs 3 times as much energy to ...
@cathoderay I just had a look back again and spotted this part of one of the plots you posted, where the current in (and to some extent the LWT) is ...
@cathoderay Lots of data here. Firstly I would start by reframing your question from 'why does my house take more energy to heat using ASHP tha...
@cathoderay Lots of data here. Firstly I would start by reframing your question from 'why does my house take more energy to heat using ASHP tha...
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Degrees of Separation
Latest Posts
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RE: How Accurate Is My DIY Heat Loss Calculation?
@editor Thanks Mars, I have been enjoying playing with ...
By kilgorexv , 4 hours ago
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New Vaillant Arotherm controls link to existing thermostats ; wired vs wireless
I am feeling baffled and worried:We are having a an Aro...
By GutoFfowc , 7 hours ago
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RE: Do I add Air Con or MVHR to existing A2W ASHP?
@rob-of-york Thank you, I’m thinking along these same l...
By Toodles , 10 hours ago
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@Mars Good questions! The downstairs unit did the maj...
By Rob of York , 10 hours ago
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RE: Questions about A2A for heating as well as cooling
@donciccio I would suggest that you take a "fabric-fi...
By Rob of York , 10 hours ago
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RE: Volumisers in Heat Pump Systems: Does Placement Matter?
@dave, I think @jamespa has probably identified the mos...
By Mars , 1 day ago
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RE: Plug and play solar. Thoughts?
My thought is simple. Bring it on and bring on plug in...
By JamesPa , 2 days ago
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RE: Heat Geek mini store vs pump size
Yes I agree, that’s why Heat Geek have most likely sele...
By Tomtheheatingengineer , 2 days ago
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RE: Who's your electricity provider and what's your tariff?
@chandykris Swings and Roundabouts, you win some…. ...
By Toodles , 2 days ago
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@tomtheheatingengineer, thank you, and welcome to the f...
By Mars , 3 days ago
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RE: HeatGeek vs Octopus surveys: puzzling disparity - any ideas why?
@majordennisbloodnok @tomtheheatingengineer For my ...
By JamesPa , 3 days ago
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RE: Is the "divide by 2900" rule still valid?
Really flow rate is a pipework limitation not a water p...
By JamesPa , 3 days ago
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RE: The good, the bad and the not that great – my heat pump installation
@burtis, I’ve followed this thread pretty much from the...
By Mars , 6 days ago
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