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Last seen: Oct 28, 2026
Its not a bad analogy However the coal is offloaded at the radiators through the bottom of the truck, so the amount offloaded (deltaT) depends on...
Surely its more likely that @cathoderay adjusted his wc curve with the PHE in place, so the settings already take account of its effect. Of course, a...
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 ...
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Degrees of Separation
Latest Posts
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RE: Free app: run the immersion / heat pump from Growatt battery & solar surplus – no Home Assistant
Please bear in mind, everyone, that in order to use thi...
By Majordennisbloodnok , 2 hours ago
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RE: The good, the bad and the not that great – my heat pump installation
@burtis Thanks for posting this and Im so pleased you ...
By JamesPa , 4 hours ago
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RE: I need help with Ecodan ASHP
@f1p It turns out there have been a solar panel install...
By Andris , 16 hours ago
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RE: 15kw pump for 225m2 1990's house - over kill?
@seaviews your installer would be right to say that the...
By GrahamF , 16 hours ago
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RE: Vaillant ecoTEC Plus - Flow Temp and Set Up
@trebor12345 That curve looks healthy to me. I woul...
By JamesPa , 18 hours ago
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RE: Tradespeople on Their Phones: What’s Acceptable When They’re Working in Your Home?
Actually, that's a very important point. I've only ev...
By Majordennisbloodnok , 1 day ago
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RE: The Changing Jet Stream Could Challenge UK Air Source Heat Pumps
@susannasaunders can I just add to @rob-of-york s comm...
By JamesPa , 1 day ago
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RE: Aerotherm and weather compensation
These are likely inked. The basic explanation is tha...
By JamesPa , 1 day ago
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RE: Electrical works for air to air heat pump
agree with above. I have not had extra costs added wh...
By Batpred , 1 day ago
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Good to hear that you found a solution. Absolutely a...
By Batpred , 1 day ago
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RE: Are there any comparisons of DHW heat stores around?
@sarahemmm I have done things the opposite way round I ...
By Toodles , 2 days ago
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RE: How will removing the standing charge on gas bills benefit heat pumps?
The BUS grant funding for 2026/27 will run out at the c...
By Rob of York , 3 days ago
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RE: Say hello and introduce yourself
@e-a-west as the good Major said, welcome to the forums...
By Mars , 5 days ago
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