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Last seen: Oct 19, 2026
My understanding of modbus is that its a master slave system. One unit must be designated the master, others are slaves. i dont know how you do this...
At this point I would like to observe that the flue fan from my gas boiler was very distinctly audible in parts of the house, as at times were some of...
@sandman1600 Im glad the analysis helps with understanding at least, that particular plot was a real goldmine. 3sq m surface area for the DHW coil i...
@arundalep thanks, very interesting.
Agree. It seems to me that if the external gauge is in the flow, ie immediately after the pump, then it would be expected that there is a pressure di...
In that case output at 40C will be 25% of quoted value, ie not a lot. Towel rails appear to be like this, options if not enough are add an elect...
Further to the above here is the system pressure measured by my Vaillant. I know that this reacts to pump head, because (a) its about 0.6bar less tha...
@jeegnesh My heating switched off altogether for three hours today, so the water pump stopped. Whilst it was off, the water pressure on the controlle...
The output is not, so far as I can tell, limited to 3.8kW when NR is active although I have only limited monitoring capability so could just be wrong....
Possibly 25mm Vs 22 mm pipes. Output depends on surface area principally, but also on form factor. A rad that is twice as tall as another will emit...
@toodles Thanks, very helpful.
I have a 7kW Vaillant and it definitely has a PWM pump. The 12kW may differ of course. This water pump can, if you wish, be turned up or down manual...
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Degrees of Separation
Latest Posts
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First you need to know how much thermal energy you'll n...
By bobflux , 4 hours ago
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RE: How quickly would you want/expect heat recovery to take from setback?
@toodles Ah, that makes sense. Your using the TRV bo...
By Singlespeed , 4 hours ago
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RE: Renewables & Heat Pumps in the News
Yes, energy seems less of a priority, even if the cost ...
By Batpred , 5 hours ago
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RE: Renewable Heating Hub Homeowners' Q&A Podcast
Come for the low-carbon homes. Stay for George Clarke’s...
By Mars , 1 day ago
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RE: Octopus Cosy 12 Heat Pump Regret: Incredibly Loud, Poor Heating & Constant Hum - Help!
@razz, as we head into the heating season, I just wante...
By Mars , 1 day ago
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RE: How should the Boiler Upgrade Scheme be reformed?
Not quite, regular A2W heat-pumps need a load of extra ...
By Temperature_Gradient , 3 days ago
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RE: Heat Geek installations: share your experiences
one thing i learnt from reading people’s comments and e...
By Batpred , 3 days ago
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RE: Cooling/heating with one unit
"The way we use A2A on a cheap overnight EV tariff is t...
By mrkfm , 3 days ago
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RE: Do I add Air Con or MVHR to existing A2W ASHP?
We have ‘signed on the dotted line’ today for a Panason...
By Toodles , 3 days ago
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RE: Heat pump branding. Clever, contemporary… or a bit too much?
...or it was there and was lost thanks to laziness and ...
By Majordennisbloodnok , 3 days ago
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Bufferless design & control of Chinese air to water monoblock hybrid heat pump in Alberta, Canada
This post is about how I successfully configured a buff...
By Tony.Stolz , 4 days ago
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The installer visited yesterday and suggested the noise...
By JamesChatz , 4 days ago
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RE: HeatGeek vs Octopus surveys: puzzling disparity - any ideas why?
Your house sounds a lot like mine. 2 surveyors each sp...
By JamesPa , 4 days ago
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RE: Heat Geek Zero Disrupt: Are We Sleepwalking Into Another Race to the Bottom?
Thats true only if you do the wrong experiment. Done c...
By JamesPa , 4 days ago
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