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Last seen: May 29, 2025
@trebor12345 Attached is the document which provides more info.
@jamespa Quick one for your information. Specs for Hitachi 3HP heat pump which one member of this forum has. Note min/max power. Ratio 2.1/11 = 19%.
@jamespa There is a lot here but I wish to deal with the fundamentals first. Firstly, you have ignored the statement by Graham Hendra that he has ...
@jamespa Firstly, I can confirm that the Daikin heat pump in the example was producing 8kW output during the cold spell in January. Regarding thi...
On the published graphs, you can put your mouse over any part of the graph to read the actual value at any point. This is NOT a calculation. I am mere...
@jamespa Sorry, I should have added the word "theoretically" as I was trying to rationalise the theory behind Grant's 8C philosophy. Whether heat pum...
@robs Thank you for this. I had forgotten about Ecodan, especially as I have one with its dangly NTC leads. I presume the example is a 5kW unit. This...
@grantmethestrength Do you know what your DT was when you were heating at -2C outside? This will give an indication of what your peak heat load was....
@pooneil I have a Gen 4 Samsung. The setting on mine is 25C @ 15C. 25C is the lowest base temperature and the flow at 16C or 17C will still be at 25C....
@pooneil It sounds like the settings are all over the place and you are maybe misunderstanding some things. Let’s get back to basics at the risk of te...
@bontwoody If you look at the diagram, at 19.00 when power is over 3kW, the DT is 5C. If you look around 11.00 when power is ~2kW, then DT is 3C. In b...
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RE: HeatGeek vs Octopus surveys: puzzling disparity - any ideas why?
Thanks for the update. Vaillant is a good choice, their...
By Batpred , 2 hours ago
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RE: To re-pipe or not to re-pipe? Moving from oil boiler to air source heat pump.
@penval, really useful update. After all the discussion...
By Mars , 8 hours ago
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RE: Who's your electricity provider and what's your tariff?
@papahuhu I prefer to look at it simplistically. We d...
By Old_Scientist , 1 day ago
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RE: How Accurate Is My DIY Heat Loss Calculation?
D'oh - of course. I shouldn't post before my brain is f...
By Old_Scientist , 1 day ago
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RE: Questions about A2A for heating as well as cooling
@rob-of-york I would concur with the underfloor insulat...
By Toodles , 2 days ago
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RE: New Vaillant Arotherm controls link to existing thermostats ; wired vs wireless
Nothing attached! I have rads but UFH makes the case ...
By JamesPa , 2 days ago
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RE: Cooling with air to water heat pumps
Passive cooling should always be the first call. Keep ...
By JamesPa , 2 days 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 , 2 days ago
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@Mars Good questions! The downstairs unit did the maj...
By Rob of York , 2 days 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 , 3 days 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 , 4 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 , 4 days ago
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@tomtheheatingengineer, thank you, and welcome to the f...
By Mars , 4 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 , 5 days ago



