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Last seen: May 18, 2026
One school of thought says put almost nothing in and instead treat only to VDI2035 which is a German standard. So far as I can see there is a lot to ...
Im not sure what your thought process is here. Are you suggesting running with a max FT of 40 rather than the max of (say) 35 that the UFH is likely ...
The nominal will be the flow rate for rad dt5 at full output. Ideally you should be looking to achieve this but.. your 16kW heat pump is likely well ...
@adam That all sounds very sensible and I agree with your analysis. Like you I turn on the immersion on the very coldest days, because I run low n...
No chance! Largely, hence my suggestion to do some experimenting with the Homely set temp set to 30C, thus taking that element of control out of ...
@chinkoa Sorry there are two separate thoughts going on which I didn't make clear: "What's the capacity of the heat pump. Flow...
Agree. I think I have given you several pointers to help track it down, its now up to you whether to pursue any or hope your installer will diagnose,...
@papahuhu sorry - confusing info in previous posts Anyway upstairs rads aren't getting to anything like the flow temp it seems so that needs to be f...
What's the capacity of the heat pump. Flow rate (l/s) x DT (say 5) x 4.2 = heat transferred in kW which needs to be greater than or equal to capacity...
I find it impossible to believe that your house heats by 0.7C, or even 0.2C, in 2 minutes, unless you live in a tent. IMHO something else is causing ...
That really, really shouldn't happen and suggests that the heat pump may be well oversized or there is some other problem eg a badly set up buffer/LLH...
Either complete Bow Locks or at best a marginal effect. The amount of energy it needs to produce is fixed by your house. If you force it to produce...
Latest Posts
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RE: ASHP Capacity loss with aging
This is a good question. The short answer IMO is yes, c...
By Mars , 1 hour ago
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RE: Daikin Altherma 3 with Fan Coils in Puglia (Italy)… Sanity Check on System Operation
Welcome @simon_jm, and this is not a dumb question at a...
By Mars , 2 hours ago
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RE: Loud noises in the night - and one for the toolbox?
Brilliant bit of lateral thinking, and a useful one to ...
By Mars , 3 hours ago
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RE: Setback savings - fact or fiction?
Yes, also the higher OAT end is possibly a smidge high ...
By RobS , 4 hours ago
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RE: UK warm homes plan - how can it be delivered?
@bobflux My view is that regulation for consumer pro...
By Batpred , 6 hours ago
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Hi Mars, I've sent you a request to connect me with a...
By sttpd1917 , 7 hours ago
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RE: Sizing an ASHP; Heat loss and kW
Annual consumption is almost certainly better than an E...
By JamesPa , 11 hours ago
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Grant Aerona R290 (15.5kW) - How is DHW Target Temp calculated?
Hello all, We have just had a Grant Aerona R290 insta...
By TaffontheTaff , 12 hours ago
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RE: Advice on Vaillant Sensocomfort
The latest Vaillant announcement I saw said that they w...
By JamesPa , 16 hours ago
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RE: Debugging my legionella immersion heater
I notice this (66 is rather hot) with my legionella cyc...
By JamesPa , 1 day ago
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RE: DIY Heat Pump Installations: Navigating Legal and Regulatory Hurdles
@transparent I thought you would spot that wind turbine...
By Batpred , 1 day ago
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RE: Octopus Cosy Heat Pump Owners & Discussion Thread
@swwils there is no logic to oversizing a heat pump. It...
By AgentGeorge , 2 days ago
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RE: Vaillant Sensocomfort Time
Thank youy for the pointer. I think I have managed to ...
By ispookie666 , 2 days ago
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RE: Forum updates, announcements & issues
I have been doing a lot of work on the site lately and ...
By Mars , 2 days ago
