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Last seen: Aug 25, 2026
Consumption is entirely dependent on house construction. My house, a 1930s solid wall build with about 70% retrofitted IWI, 30cm loft insulation, d...
I agree with those who say don't/you cant do it, see regulation 5.4. The only 'get out' is that this is guidance which, 'in the opinion of the Sec...
I don't have the full specs to hand (Grrant don't publish them AFAIK, but Chofu, the oem, might) however a 4:1 turn down for an a2w pump is a good fig...
All a2w heat pumps work this way so far as I know, because it makes sense, Vaillant is no different. Ditto gas boilers with weather compensation. O...
I guess that in principle, with the right plumbing, you could run both together at the ft of the dhw. Lousy efficiency and the output is divided betw...
And gas boiler that operates weather compensation does exactly the same, for the simple reason that you need a higher flow temp for dhw than for space...
Yes mine also. It seems a sensible approach to me, much more sensible than making DT across each emitter the same in a system where the aim is to ope...
I completely agree. However DT can only change by a small amount (~5C) in a tolerably well adjusted setup and each degree it changes is equal to half...
I think because 6-8kW, which a 22mm pipe can deliver at a typical DT of 5, gives a sufficiently fast recovery time for many people and... 22mm gives...
Well exactly that. Much of the discussion above focussed on 'delta T' being in this case the difference between flow and return temperatures. But th...
I must say that the recent posts about buffers are most encouraging. When I first embarked on this journey it seemed almost heresy to suggest on a pu...
Because it's been done in a completely muddle headed way. The requirement for accessing a grant has been conflated with both planning and building re...
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Degrees of Separation
Latest Posts
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RE: Volumisers in Heat Pump Systems: Does Placement Matter?
@dave, I think @jamespa has probably identified the mos...
By Mars , 9 hours ago
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@kilgorexv, I actually think doing your own calculation...
By Mars , 9 hours 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 , 23 hours 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 , 2 days ago
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RE: HeatGeek vs Octopus surveys: puzzling disparity - any ideas why?
@majordennisbloodnok @tomtheheatingengineer For my ...
By JamesPa , 2 days ago
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RE: Do I add Air Con or MVHR to existing A2W ASHP?
There is scope for product development here. I for one...
By JamesPa , 2 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 , 5 days ago
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RE: Starting Our Heat Pump Journey: 1962 build 3 bed detached house
First time poster here but I can share my experience as...
By SCH , 6 days ago
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RE: Is it the house or the equipment?
...which, I've found out, is pretty much impossible to ...
By Majordennisbloodnok , 6 days ago
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