They certainly don’t measure wind and they have no idea what’s going on. All I know is that we’ve never had an issue in the year we’ve had it. Obviously wind will have an effect on how quickly the house cools down but with two layers of brick and an insulated cavity between the room and the outdoors the effect is going to be very much at the margins. It’s just not something to be worried about; as quite often on the Forum people can dream up problems that just aren’t there.
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A cold wind absolutely strips the heat from my house as the insulation is quite poor so yes, it definitely can be an issue depending on insulation and house orientation etc.
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To all of you commenting on heat pumps, I can add that I have an ASHP with well designed microbore. The small pipes only run a relatively short distance to and from numerous manifolds fed by 22mm pipework. Whilst 15mm might be better it would not fit inside the ducting in the rendered walls where it drops from the 22mm pipes flowing through eves and the upstairs floors. The downstairs is divided into two zones for living rooms and bedrooms. The upstairs bedrooms form a third zone.
It is a waste of money using zone valves with a heat pump because heating only a portion of the house forces the 12kW heat pump to operate below 40%, a region where efficiency starts dropping and the pump just cycles. Apart from heating cold radiators up to temperature the pump operates at 50-60%.
I run mine with a flow temperature of 35c regardless of outside temperature. If it is colder I run the ASHP almost continuously, but always in the winter from 11:30pm to 10am since December. The aim is for the temperature to drop no more than 2c while it is off. We are EPC of C for a very large 6 bedroom 3 reception room property of 300m2 floor area on two floors of 150m2.
What I find is that increasing the flow temperature below about 2c when defrost cycles start is counterproductive because the interval between defrosting decreases from 50 minutes to 30 minutes at -8c. In this time the the water cannot reach the demanded flow temperature. The extra heat removed from the air causes the heat exchanger in the heat pump to ice up quicker.
Adding fans under all the radiators has greatly improved the cold weather performance. Bit like windchill outside in reverse!
The daily electricity peaked at 41kWh on Monday and was 22kWh on Friday. Hourly rates run from 1.5kWh to 1.9kWh for heating.
Phil
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Agree. An exposed and poorly insulated detached property would be massively impacted by wind. This would need to be taken into consideration by the ASHP designer, and challenged by the customer.
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That makes sense to me. Microbore is only the last few metres to each rad of a system of mostly 22mm pipe, sometimes also 28mm. I don’t think anyone is claiming that it’s optimal compared to 15mm, but it’s surely going to work. Everything is a design compromise to some degree.
Mitsubishi have said that their heat pumps can handle microbore, and suggest that it should be left in place in order to simplify installation if we want to push carbon emissions reduction to anywhere near proposed targets.
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Mine is 28mm the short distance to the zone valves and then 22mm. It was put in 36 years ago. The ASHP installer did replace all the radiators.
Our local Mitsubishi installer wanted to replace all the pipework at a ridiculously cost. I did not proceed with them, but chose one 6 miles away rather than 1. My simple ASHP does what I tell it to. It does support weather compensation but having tried it I don’t think it is as effective as on/off. It runs on a program for the bulk of the time which I override if it is colder during the day.
Phil
We went for a lovely walk today through the snow in the English Garden.
Do we perhaps need a separate heat pump thread?
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Might be better in Solar Generation thread ?
I was just going to say all well and interesting but what about your heat pump.
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I love the irony, particularly for the UK, of any link between when PV generates and when you most need a heat pump. There can be a few days, but mostly gray and dark cold days……
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Went for my quarterly bloods. Miserable weather and I’m still not fully first over my pneumonia and flu so I bussed what would otherwise have been a 25 minute walk and then, having got wet anyway despite my layers, headed to the cinema.
Spent the afternoon putting in place arrangements for tomorrow night when the offspring’s band make their Manchester debut in the Northern Quarter as part of their first proper venture out of Sheffield. Manchester tomorrow, Liverpool Sunday and then Brighton.
Think I’ve finally persuaded that, no, Mrs. H. and I will not be hosting eight people.
New track out at midnight tonight is the first product of their session with Alan Smyth (Arctic Monkeys, Pulp and Richard Hawley).
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Hope all goes well, and that you managed not to get a chill from the rain
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I think my brain has been fried rather than chilled. It has only just registered why one might issue a track called “Vampire” at midnight. Doh…
Congratulations to the offspring Mike.
Let’s just hope that this proves to be the ONE highlight of your week, even though I expect it probably won’t be……
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I have my usual bad vibes. We’ve won 5 in a row in league and cup. Logic says it can’t possibly get to 6. Things just don’t work like that.
Bought this 10 blade razor pack as it was the cheapest way of buying new blades.
10 blades, 14 months, who are they trying to kid?
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I use the Lidl own brand, almost as good, far cheaper.
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Lidl’s Parkside brand of tools is also excellent value for money. More than good enough for DIY for little money. Spending the same in local building/diy shop will get you something far, far worse. I’ve sometimes wondered if they’re loss leaders.
I guess it extends to these kinds of tools as well.
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I’m completely done with the Gamma / Karwei et cetera. They have a massive mark up, I think they sell stuff which they buy for 1 euro for 8 euro or so.