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Last seen: Jan 28, 2026
Hi @iancalderbank , Swapped over probes looked like a similar diff initially, but now since running speed 3 on secondary pump these temps seem to ha...
Other photos seem to show a size diff that would indicate 28mm main or more, then 22mm, then 15mm copper at the end. The 22mm branches seem to be for...
Thanks @iancalderbank - waiting for the plumber to confirm the sizing as that was just the builder's guess
@iancalderbank - builder believes it's a standard 22mm flow and return into a 15mm drop for the rads. But is confirming with the plumbers
So all in all I see: Top right of LLH versus pipe in plant room leading to heating zone: 1C drop Total drops with drop from zone pipe to r...
Thanks Ian, I'll ask this with the plumbers. I think upstairs looks to be running of this also, as I know that's approx where a rad is above this ro...
Hi Toodles, don't think any outside. The plant room is all lagged. And the ASHP has a pretty heavy duty underground insulated set (I think further b...
From photos I have of when the project was in progress looks like the pipe work is in the ceilings, plastic, then runs down the walls are metal. Thos...
Thanks Toodles.Here's probably a stupid question. I notice: (Grant panel) LWT on Grant panel (I think this never shows .5C rounded to nearest 1)...
Thanks Toodles, I hope so for sure. That 1.5C max uplift to LWT puts about 1C extra into the system at current temps, and really felt that upstairs. ...
I think it’s safe to say the rads downstairs appear to be the issue. Keeping upstairs on but reducing lock shields down does seem to have reduced cy...
thanks Derek. I’ll try and push for the LLH to volumiser as well as simplification of zones. The DHW cycle heating upstairs was an oversight of the he...
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Latest Posts
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RE: Surface mount or bury primaries for heat pump installation?
The installation is almost done! I've written up two ...
By tomasmcguinness , 6 hours ago
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RE: Adventures in heat loss calculations
As others have said, well done, and thank you for posti...
By cathodeRay , 6 hours ago
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RE: Glass lined Cylinder for private water supply
This has turned into a fascinating little rabbit hole. ...
By Mars , 15 hours ago
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RE: Switch suitable to change between two inverter CT's
Last winter my battery ,32KWh, could run the house com...
By Jancold , 16 hours ago
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RE: How Accurate Is My DIY Heat Loss Calculation?
@rob-of-york Thank you for that, whilst familiar with t...
By kilgorexv , 16 hours ago
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RE: HeatGeek vs Octopus surveys: puzzling disparity - any ideas why?
Agree with Major. And even if I was very happy with ...
By Batpred , 17 hours ago
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RE: Is the "divide by 2900" rule still valid?
There is another estimator that you could use, a formul...
By Rob of York , 20 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 , 3 days 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 , 4 days 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 , 4 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 , 4 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 , 4 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 , 5 days ago
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@Mars Good questions! The downstairs unit did the maj...
By Rob of York , 5 days ago



