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Post by Dan Dare on Jun 10, 2023 10:57:09 GMT
Air-to-water systems are essentially silent inside a house. The only acoustic 'pollution' comes from the compressor which is outside and makes as much noise as a domestic refrigerator.
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Post by Orac on Jun 10, 2023 11:04:17 GMT
My rough guess is that a compressor that makes the noise of a domestic refrigerator (all things being equal) will have about the power of a domestic refrigerator. If you sneak behind industrial refrigerators to have a listen, you'll notice a difference. Domestic refrigerators are quite low power units and most people (certainly me) don't leave the door open or put them on a low setting that can't be reached. People have, after having had installations completed, asked for a reworking so the compressor can be at the end of the garden.
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Post by colbops on Jun 10, 2023 12:23:27 GMT
Of course, you are absolutely correct. Over a heating season in the UK an air source heat pump will typically have an average CoP of between 3 and 4 In warmer temperatures it'll be way above 4, and in lower temperatures it will be as low as 2 - 2.5 to put that into context, an electric panel heater has a CoP of 1 The figures you quote here are (in effect) 'best case scenarios' - there are many cases in which an expensive installation actually appears to waste electricity (or rather, do no better than a heater). It's a bit of a dark science and the overall effectiveness of the system(the measurement that's important) can be disappointing if you take into account the complexity of such installations. A lot of people have ended up with expensive systems that cannot adequately heat their houses and make quite a bit of noise. No they aren't. I've given you a performance range to explain where the average CoP comes from. Nothing best case about it. There is no way an electric heater can ever be more efficient than a heat pump. Even the most poorly installed and commissioned heat pump will have a CoP of 2. An electric heater can never have a CoP higher than 1. Its not a dark science at all, the science is relatively simple. 'Overall Effectiveness' is a little vague so what you mean by that and how you measure it only you can explain. If anyone ends up with a system that cannot adequately heat their home and/or is too noisy then they've bought the wrong system for their needs. You can't blame the tool if you use the wrong tool for the job. |
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Post by Dan Dare on Jun 10, 2023 12:26:28 GMT
I just checked the specs for mine. It has heating capacity of 10kW for floor heating and refrigerator-level noise level of 47 dB. At a COP of 4 we're looking at an effective compressor load of 2.5 kW.
Heating capacity is more than adequate and overall energy consumption is relatively modest too: up to 5422 kWh for heating plus 880 kWh for DHW (55C) = 17 kWh/day. At current rates of €0.16/kWh that equates to less than €3 per day on an annual basis, or €5-6 per day during the heating season.
There is a fixed limit to the lengths of the refrigerant lines between external and internal units so if 47dB is too loud locating the compressor to the bottom of the garden is not really an option. Fortunately it isn't necessary.
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Post by Orac on Jun 10, 2023 12:39:40 GMT
The figures you quote here are (in effect) 'best case scenarios' - there are many cases in which an expensive installation actually appears to waste electricity (or rather, do no better than a heater). It's a bit of a dark science and the overall effectiveness of the system(the measurement that's important) can be disappointing if you take into account the complexity of such installations. A lot of people have ended up with expensive systems that cannot adequately heat their houses and make quite a bit of noise. No they aren't. I've given you a performance range to explain where the average CoP comes from. Nothing best case about it. There is no way an electric heater can ever be more efficient than a heat pump. Even the most poorly installed and commissioned heat pump will have a CoP of 2. An electric heater can never have a CoP higher than 1. Its not a dark science at all, the science is relatively simple. 'Overall Effectiveness' is a little vague so what you mean by that and how you measure it only you can explain. If anyone ends up with a system that cannot adequately heat their home and/or is too noisy then they've bought the wrong system for their needs. You can't blame the tool if you use the wrong tool for the job. What is important is the effectiveness of the system in heating your house. In the real world it is far simpler matter to get a standard heating system to do this adequately, than arrange for a heat pump to reliably do the job adequately - one pitfall is that a more powerful heat pump system is a lot more expensive than a less powerful one. It is a dark science because what is adequate is not such a simple matter as with a standard system. Yes you can theoretically fit any house with an adequate heat pump system - however, back in reality it doesn't quite work like that - hence significant numbers of people with inadequate systems that do little but make a lot of noise. |
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Post by Bentley on Jun 10, 2023 13:23:39 GMT
I’m sure a lot of people who criticise fossil fuel vehicles don’t know how combustion engines work and quite a few EV fans have no idea how the batteries , motors and computers in the vehicle work. I disagree. People who criticise fossil fuel vehicles criticise a specific attribute they understand very well. I disagree. I doubt that Greta Thunberg and the just stop oil vandals knows much about internal combustion engines . They just know that someone told them that they will make everything hotter. |
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Post by zanygame on Jun 10, 2023 14:51:37 GMT
See my explanation to John of Gwent. This sentence from you "Rather than using some mechanism to pump heat, you instead just heat something up." somewhat belied this. I assumed that if you knew how a heat pump worked you would know its twice as efficient as a conventional heater and would suggest swapping one for the other so glibly. It multiplies the heat, it takes in heat at minus 5 and multiplies it to plus 22. That is all I meant. By |
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Post by zanygame on Jun 10, 2023 14:53:42 GMT
My rough guess is that a compressor that makes the noise of a domestic refrigerator (all things being equal) will have about the power of a domestic refrigerator. If you sneak behind industrial refrigerators to have a listen, you'll notice a difference. Domestic refrigerators are quite low power units and most people (certainly me) don't leave the door open or put them on a low setting that can't be reached. People have, after having had installations completed, asked for a reworking so the compressor can be at the end of the garden. I posted a video with someone showing how quiet they are. You are wrong on this. |
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Post by zanygame on Jun 10, 2023 14:59:48 GMT
No they aren't. I've given you a performance range to explain where the average CoP comes from. Nothing best case about it. There is no way an electric heater can ever be more efficient than a heat pump. Even the most poorly installed and commissioned heat pump will have a CoP of 2. An electric heater can never have a CoP higher than 1. Its not a dark science at all, the science is relatively simple. 'Overall Effectiveness' is a little vague so what you mean by that and how you measure it only you can explain. If anyone ends up with a system that cannot adequately heat their home and/or is too noisy then they've bought the wrong system for their needs. You can't blame the tool if you use the wrong tool for the job. What is important is the effectiveness of the system in heating your house. In the real world it is far simpler matter to get a standard heating system to do this adequately, than arrange for a heat pump to reliably do the job adequately - one pitfall is that a more powerful heat pump system is a lot more expensive than a less powerful one. It is a dark science because what is adequate is not such a simple matter as with a standard system. Yes you can theoretically fit any house with an adequate heat pump system - however, back in reality it doesn't quite work like that - hence significant numbers of people with inadequate systems that do little but make a lot of noise. People have claimed the old methods are better since they invented the wheel. You have been told by people who have heat pumps that they are quiet, cheap to run and effective at heating a house. Yet still you insist the old ways are better. |
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Post by zanygame on Jun 10, 2023 15:01:56 GMT
I disagree. People who criticise fossil fuel vehicles criticise a specific attribute they understand very well. I disagree. I doubt that Greta Thunberg and the just stop oil vandals knows much about internal combustion engines . They just know that someone told them that they will make everything hotter. Greta Thunberg knows more about vehicle emissions and their effect on climate than you ever will. Still if you can't fight the science best fight the messenger. That surely works. |
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Post by Bentley on Jun 10, 2023 15:28:16 GMT
I disagree. I doubt that Greta Thunberg and the just stop oil vandals knows much about internal combustion engines . They just know that someone told them that they will make everything hotter. Greta Thunberg knows more about vehicle emissions and their effect on climate than you ever will. Still if you can't fight the science best fight the messenger. That surely works. If the eco worrier zealots have to be fronted by a teenage autistic girl then it’s says a lot about the eco worriers zealots . Greta knows nothing about the science because she doesn’t speak about the science . She spouts the usual sound bites , safe in the knowledge that a teenage autistic girl is unassailable no matter how ignorant . |
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Post by zanygame on Jun 10, 2023 15:32:24 GMT
Greta Thunberg knows more about vehicle emissions and their effect on climate than you ever will. Still if you can't fight the science best fight the messenger. That surely works. If the eco worrier zealots have to be fronted by a teenage autistic girl then it’s says a lot about the eco worriers zealots . Greta knows nothing about the science because she doesn’t speak about the science . She spouts the usual sound bites , safe in the knowledge that a teenage autistic girl is unassailable no matter how ignorant . They don't have to be fronted by anyone, but perhaps Sir David Attenborough is more to your taste. Greta spouts what she believes is critical to the survival of the planet as we know it. I seriously doubt you have ever listened, so you wouldn't know. |
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Post by Bentley on Jun 10, 2023 15:41:42 GMT
If the eco worrier zealots have to be fronted by a teenage autistic girl then it’s says a lot about the eco worriers zealots . Greta knows nothing about the science because she doesn’t speak about the science . She spouts the usual sound bites , safe in the knowledge that a teenage autistic girl is unassailable no matter how ignorant . They don't have to be fronted by anyone, but perhaps Sir David Attenborough is more to your taste. Greta spouts what she believes is critical to the survival of the planet as we know it. I seriously doubt you have ever listened, so you wouldn't know. Neither of them are scientists . Attenborough knows that unless he toes the line he will go the way of David Bellamy and Jonny Ball. Thunberg is just a mouth piece spouting what she is told to say. |
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Post by zanygame on Jun 10, 2023 15:54:50 GMT
They don't have to be fronted by anyone, but perhaps Sir David Attenborough is more to your taste. Greta spouts what she believes is critical to the survival of the planet as we know it. I seriously doubt you have ever listened, so you wouldn't know. Neither of them are scientists . Attenborough knows that unless he toes the line he will go the way of David Bellamy and Jonny Ball. Thunberg is just a mouth piece spouting what she is told to say. And then when the scientists say its happening you dismiss them as well. |
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Post by Bentley on Jun 10, 2023 16:03:51 GMT
Neither of them are scientists . Attenborough knows that unless he toes the line he will go the way of David Bellamy and Jonny Ball. Thunberg is just a mouth piece spouting what she is told to say. And then when the scientists say its happening you dismiss them as well. I don’t dismiss anything. I have concerns about eco worriers knee jerk dismissal of anyone who doesn’t agree with them . We had it in here , two posters who claimed that gas engineers know nothing about heating systems. The eco worrier agenda has become a quasi religion ..sending out autistic children and old TV sages to spread the message . |
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