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Last seen: May 24, 2026
@gary some the trends you've posted show the LWT is at the setpoint. They also show the setpoint is changing and they show the compressor frequency ...
Hello, I confused about why this is a problem for you. Is your house not getting warm enough? Thanks Bob
@gary I'll try and help, but at the moment I'm not really sure what the problem is. <rant> On a more general note, I read threads like this...
The lower the DT the higher the flow rate. The lower the DT on the heating water side, the hotter the average temperature of the heat emitter, so th...
@jamespa I don't know where this comes from. I've heard a variety of numbers mentioned for heating design. 10C, 5C, 7C. I think it comes from ...
Hello @jamespa I've attached a spreadsheet which attempts to show how a heat pump compressor system works. The gas enters the compressor as a s...
OK, so I'm just thinking out loud here: You loose energy through the walls, roof, and draughts - anywhere else? The 10% lost energy could be going...
Hello, sorry I've been quiet for a while. In CathodeRays case the plate heat exchanger was acting as restriction in the flow of energy from the heat...
@cathoderay at constant room temperature, energy in = energy out Q = UA.DT tells you how much energy flows through an object, in this case a wall, w...
Slicing and dicing data can sometimes be fun, but it's often frustrating. I often start by asking "what do I think i'm looking for". So..."does se...
@cathoderay what would the plot look like if you used (Inside temp - Outside temp) as the x-axis? If Q = UA.DT the gradient of the trend would be UA...
@transparent, thank you. That makes sense. Much appreciated. Regards Bob
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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 , 52 minutes ago
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RE: To re-pipe or not to re-pipe? Moving from oil boiler to air source heat pump.
Sooooo, what did we do in the end? We approached three ...
By Penval , 1 hour 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 , 7 hours 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 , 8 hours 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 , 9 hours ago
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RE: Cooling with air to water heat pumps
Passive cooling should always be the first call. Keep ...
By JamesPa , 10 hours 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 , 1 day ago
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@Mars Good questions! The downstairs unit did the maj...
By Rob of York , 1 day 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 , 2 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 , 2 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 , 3 days ago
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@tomtheheatingengineer, thank you, and welcome to the f...
By Mars , 3 days ago
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RE: HeatGeek vs Octopus surveys: puzzling disparity - any ideas why?
@majordennisbloodnok @tomtheheatingengineer For my ...
By JamesPa , 3 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 , 4 days ago



