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Last seen: Aug 16, 2026
@goody I couldn’t agree more! I just meant they usually get it wrong in the opposite direction and leave a grossly oversized heat pump 😁
@alfapat No it wasn’t attached to the email. Can you resend it please.
@alfapat Im even more confused now as looking at the house I wouldnt have guessed more than 8kW would be needed. Thats not an exact science I know but...
@alfapat The lockshield valve is the one opposite the TRV. Heat pumps dont play well with TRVs and they are not necessary when using water law. Just s...
@alfapat So the EPC pretty much matches the heat calculation. By all means tweak and see it that helps. If it doesnt then try to look at any upgrade...
@cathoderay I think you should qualify this with Air to Water heat pumps. Air to Air are quite capable of rapid heating for short periods of time in a...
@goody Its unusual for a heat pump to be undersized under the MCS protocols, its usually vastly the opposite. Cant you just swap it out for a bigger o...
@zoomuno You dont have to run it 24/7. I dont. However if you really only use the heating very sparingly then I think perhaps and air to air heat pump...
@goody I can only assume you had a terrible install? My heat pump is much cheaper to run than the gas combi I had previously and my house isnt very we...
@alfapat So the problems you have are that your house has a large heat loss (Im assuming it is a big house), your system was designed to run at a h...
@alfapat so buffer tanks act as a big roundabout for the water. Flow comes in from the heat pump and back and water goes to the heating circuit and ba...
@alfapat OK. thanks for the information. It looks like your system was designed to run at 50C when at -4C outside. The yearly electricity use for s...
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Latest Posts
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RE: Who's your electricity provider and what's your tariff?
@old_scientist Have you ran the numbers as to which ...
By Papahuhu , 48 minutes 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 , 3 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 , 4 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 , 5 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 , 6 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 , 22 hours ago
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@Mars Good questions! The downstairs unit did the maj...
By Rob of York , 22 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 , 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


