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Post by peterboat on Dec 28, 2020 11:03:06 GMT
The thing with air source heat pumps is that they need a fan to push air through the radiator, and they can be noisy. There is one on a building near us - when I say near, I mean about 200 yds away. In the still of night you can hear the faint low frequency rumbling of this fan despite it not even being in line of sight. If I was going for a heat pump type thingy, I'd go for ground source. Although I suppose you do need a fairly big bit of land for that to work. Cost-wise, whilst you can get 3 or 4 times more heat out than electricity you put in, a modern high efficiency gas boiler is cheaper to run per kw of heat put into the house because gas is about 6 times cheaper than electricity per kwh. And a lot less faffy. OK if you can run your heat pump from renewabe leccy (solar, wind, hydro) then it is "green" but we all get the same leccy out of the plug, some is green, some is nuclear and some is fossil fuel derived, at about 25% efficiency. They can do it with a borehole as well Nick Auchencairn post office has it, very efficient mid winter and windows open for cooling!! The garage opposite has air source heating for the office again works great and its helped the damp issue as its dry air. Philip at the Farm has used the field next to him and as I said has a huge solar array to power it, it works so well the main farmhouse is going to converted as well, it already has the solar to power it up,
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Post by peterboat on Dec 28, 2020 11:08:36 GMT
Better to use a small keel tank Jim, less to go wrong and no pipes to get stuck on owt. Will there be sufficient surface area though, I looked up the size of garden needed for groundsource pipework layed in trenches and it's a fair amount. peterboat , are you taking advantage of the grant? Solar thermal uses up the 5k nicely, with the 20% ? contribution, coming in at around 7k. Or are you virtually (virtuously?) off grid already? Our electric supply is rubbish Jim I tend to burn wood that is well seasoned in the Rayburn. As for the keel cooling think how many kilowatts a diesel engine needs to cool it same the other way for extracting the heat from the canal? We are looking at the grant but our issue is the garden is the size of a stamp! and not much hope of boring a hole in the garden either
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Post by Jim on Dec 28, 2020 11:28:03 GMT
Will there be sufficient surface area though, I looked up the size of garden needed for groundsource pipework layed in trenches and it's a fair amount. peterboat , are you taking advantage of the grant? Solar thermal uses up the 5k nicely, with the 20% ? contribution, coming in at around 7k. Or are you virtually (virtuously?) off grid already? Our electric supply is rubbish Jim I tend to burn wood that is well seasoned in the Rayburn. As for the keel cooling think how many kilowatts a diesel engine needs to cool it same the other way for extracting the heat from the canal? We are looking at the grant but our issue is the garden is the size of a stamp! and not much hope of boring a hole in the garden either
Oh, I don't know, a hole in your garden might stop it flooding if you don't plug the top. Ground source is about a third dearer than air source too, due to the groundworks cost. I'm hoping the fan isn't too noisy on the airsource gubbins, it's below our bedroom window and we like to have a window open at night.
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Post by Isambard Kingdom Brunel on Dec 28, 2020 16:42:21 GMT
The racket of the air heat exchanger fan will be bad, and as it gets older it will get worse. The volume of air that has to be moved in winter with a heat pump is huge, it will be like living in a tornado.
You need it to be sited as far away as possible. Noise ratings vary between 42 and 60 decibels, too noisy under your open bedroom window.
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