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Last seen: Jun 26, 2026
OK, first full monthly billing period with Cosy Octopus, and, combined with a 6.5kWh battery charged at cheap rate periods, it has saved me 25% compar...
Grant make the assumption that higher leaving water temperatures have a higher delta T between flow and return, compared to lower temperatures. For th...
The economy of manufacturing scale comes into it, with Octopus' backing, RED will have more purchasing power for the major ASHP components. I'm person...
@marvinator80 good on them. I wish my installer hadn't now, as it adds nothing and probably robs efficiency. It may be coming out one day. I don't nee...
@marvinator80 WOW! Absolutely fantastic. Very tidy.Out of interest, did your installer fit a low loss header and secondary pump or not? I don't see on...
That's pretty good. I'm sitting around 920kWh for the last rolling month, but that's mains power. My solar PV contribution has been around 150-180kWh ...
It's a lot better than HIVE, which was cycling 5+ times per hour with me! Just leave it set to a high temperature and use climate/weather compensation...
@sirpatchuk1980 ASHPs work best when continuously running. Less wear and tear and better efficiency. The outdoor unit has in built stop/start cycle pr...
@sirpatchuk1980 (sorry @aceshigh) just chipping in. Looks like your Grant controller is hidden away with some of the pipework and system components. I...
Hello @sirpatchuk1980, welcome. Lots of useful info on here on how to maximise efficiency of ASHPs, especially retrofits. First things first, a bit of...
Grant do their Vortex oil boiler as a hybrid - basically an outdoor vortex combustion boiler plonked on the same base as one of their (well, Chofu's) ...
Hermetic refrigeration compressors are suction gas cooled, using sub-cooling of the refrigerant vapour. For most ASHPs, the compressor compartment is ...
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Degrees of Separation
Latest Posts
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New Vaillant Arotherm controls link to existing thermostats ; wired vs wireless
I am feeling baffled and worried:We are having a an Aro...
By GutoFfowc , 2 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 , 5 hours ago
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@Mars Good questions! The downstairs unit did the maj...
By Rob of York , 5 hours ago
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RE: Questions about A2A for heating as well as cooling
@donciccio I would suggest that you take a "fabric-fi...
By Rob of York , 6 hours ago
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RE: How Accurate Is My DIY Heat Loss Calculation?
Any idea how efficient your gas boiler is? Is it a 50 y...
By Old_Scientist , 11 hours 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 , 23 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 , 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 , 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: 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 , 6 days ago



