billt

Simple, most people don't have a huge choice in the houses they buy. They are limited by money, area and availability. Despite complaints about energy costs, they are still fairly cheap so, if you can afford to buy a house you're unlikely to be troubled much by energy use. Location, location, location is still most important to most people. We're an example of that. For nearly 30 years we lived in an old characterful house in an idyllic location. I spent a lot of effort to improve its performance and it wasn't too bad when we left. For various reasons we decided to move 4 years ago and spent a lot of time looking around the county for a new house, including looking at building plots (I've always wanted to build a house). There were very, very few houses and no plots which met our desires. In the end we bought a house which filled most of our wants (close to town centre, trees and greenery visible, flat garden, no stairs). Bear in mind that there are 2 of us so we have to compromise! We bought a many times extended bungalow with a terrible layout from a heat loss POV and various levels of poor insulation. The EPC was D - 58. We're doing our best to improve the performance, but there will be a limit to what is achievable. The idea of knocking it down to rebuild is an unaffordable joke (although it did cross my mind for a nanosecond). Although I've long tried to reduce our energy consumption of all types other considerations can override that.

We're on the edge of a town on a big plot and the neighbours aren't affected by the noise as there is distance and fences between them and the noise source. It annoys me though, having been mislead into thinking that ASHPs aren't that noisy. I was under the impression that system design for heat pumps meant that they should be run reasonably hard to gain maximum efficiency. Ours was designed that way and does run at maximum output for a significant amount of time. Of course the will all run at close to maximum output when recharging a cylinder so that's 30-40 minutes of peak noise a day. I think that the bungalow units are probably 5 or 7kW ones, but, yes, on a cold evening they probably were running flat out and making lots of noise. So heat pumps aren't noisy if they're not doing anything!

It isn't nonsense. Even the manufacturers say that their heat pumps make noise. Samsung give a figure of 48-63dbA at some unspecified distance. Vaillant say Sound pressure level of 55dB sound pressure level of 47dBA at 1M, 33dBA at 5M for the 7kW model. Vaillant are among the quietest heat pumps and they aren't quiet. 3 bungalows were recently built near us and were fitted with Vaillant heat pumps. Go out on a cold evening and you can hear them roaring away from 30M away.

I'm starting to get annoyed when I see this said. They are noisy, some more than others, although you wouldn't think so from all the youtube videos and articles from enthusiasts saying that they're almost silent. I fitted one a few months ago and it produces really annoying noises. The worst is from the compressor, but the noise varies dramatically as conditions change. Varying noise is more irritating than steady noise. (And it's more irritating than the noise that the old gas boiler made.) Strangely, I've just fitted an air to air heat pump and that is much less objectionable. Of course it's less powerful, but the noise is more consistent, more like white/pink noise and lower in level, but it's still noise. There's also an ASHP for the swimming pool. That also so makes noise, less objectionable than the heating ASHP, but it's still somewhat noisy.

I'm using the Open Energy Monitor heat pump monitor. https://shop.openenergymonitor.com/level-3-heat-pump-monitoring-bundle-emonhp/ The full kit is expensive, but I like to know what's going on and I'm not too sure that the readings given by the heat pump are accurate. It is very helpful when setting the system up. If you want to look at other systems there are quite a few online at https://heatpumpmonitor.org/

You might be being a bit premature. The CoP of the Gen 6 isn't great at low temperatures, and if you are having defrosts they can knock 6-8% off the output. My overall CoP when the outside temp was freezing or below has been 2.4 to 2.6, but the SCoP so far is 3.77

You can run Homeseer under Linux. Mine runs on a Raspberry Pi 4. It also has an instance of Home Assistant running on it, an old version. With that version you had to delve into yaml for anything but the simplest stuff so I haven't played with it much. It may have improved since then. One thing that I did find was that it could talk to DeConz at the same time as HomeSeer, so if you're using DeConz it should see all your Zigbee devices and you can control them from both HomeSeer and Home Assistant. I've moved to ZigBee2MQTT and MCSMQTT so Home Assistant no longer sees Zigbee devices.

That depends on whether you look at the headline marketing guff or the actual specification. I have a Samsung heat pump and an Open Energy heat pump monitor and the performance has matched the specification pretty closely over a range of outside air temperatures. Yes it's worse in cold damp conditions, but the spec tells you that.

Depends what you mean by proper data. A defrost energy calculator has recently been added to the Open Energy Monitor heat pump app, so you can see data from lots of monitored systems at https://heatpumpmonitor.org/ There's a discussion on defrosting at https://community.openenergymonitor.org/t/ashp-sizing-for-freezing-conditions/24802/60 My system shows a calculated energy loss of 7% for defrosting, but these are quite extreme conditions. (-6C last night and 94% rH.

It's a Samsung Gen 6 8kW. It was cheap and I was trying to spend as little as possible, unfortunately spec creep occurred and tthe system ended up more expensive than initially expected. I would have done better to have spent an extra 2k on a Vaillant Aerotherm+. Isn't hindsight wonderful? The SCoP is 3.97. For the first few weeks it was about 4.4 but the cold damp weather has had its effect.

We had only 12 days when the mean temperature was below zero in the last 365 days, so I decided that, in the rare event of needing supplementary heating a fan heater would do. I would expect the effect of a really cold day would be to reduce the room temperatures slightly, so it wouldn't be necessary to add extra heating, just add an extra jumper. Yes, it is a lot. 1 - the loft insulation has been seriously disturbed and not replaced/topped up yet. 2 - the CH pipe insulation hasn't been finished. It's a mongrel building with parts of various ages and generally poor standards of construction, which are mainly not practicable to improve. The windows aren't too bad though! We've had gas consumption up to 290kWh a day last December. So far the heat energy used is looking slightly less than the gas energy used on similar days even though the old system had every room individually controlled and timed. The heat pump is running 24 hours a day. What it does demonstrate is that it is possible to run a heat pump in an old leaky building with low flow temperatures and still get a reasonable CoP.

Mine is defrosting all the time. It's been very humid for a few weeks, lots of rain, and cold. However, the reason is almost certainly that I undersized the heat pump in an effort to run it efficiently. The system was designed for -3C with a flow temperature of 35. The result is that the heat pump is running continuously at full output, so freezes up quickly. It is maintaining an adequate indoor temperature at low outdoor temperatures, but there's no leeway.

I guess that the set temperature (dashed line)is 21 degrees during the heating period. The 16 degrees in the top line is probably the current set temperature. That's a good idea about a local heat source. If it was the heat pump defrosting the shape would be the inverse of that. Fairly long period of high temperature, dropiing for a few minutes during the defrost time.

PVGIS gives an estimate of average production. It isn't a prediction. Solar energy is highly variable, especially at this time of year when there's a very small period when the sun is high enough to generate anything. The low sun angle is likely to make any shading by trees etc worse. Our approx. 15kW array generated 3 kWh on Monday, not that much more than yours, proportionately, and we are a lot further south. Trying to be self sufficient in electrical energy in the UK is not economically possible, and probably not practicslly possible either. FWIW PVGIS predicts 377kWh generation for November. In 2021 it generated 276kWh, 2022 201 kWh and this year looks to be 310 kWh if we get 2 days of sun as forecast.

Economy 7 is just a tariff, no technology involved. I would expect that you will have a smart meter installed, you may not get a choice. You should check the rates carefully. Economy 7 usually has a large increase in day rates; unless you use a significant part of your electricity during the night time period it can work out more expensive than a standard tariff.

No. You balance the radiators with the TRVs removed or fully open. Once the lock shields have been adjusted the system shouldn't need rebalancing. You can shutdown radiators with the TRVs with impunity.

That's another misleading conflation of 2 separate issues. Yes, you want to insulate as well as you can whatever the source of heat. However, it is possible to use a heat pump effectively in an old, leaky building, you just have to design the system correctly. Our house is old in places and not terribly well insulated, but I've installed a heat pump system with a design flow temperature of 35C and it is heating the house perfectly well, with a SCOP so far of 4.36 so cheaper to run than gas even on standard rate electricity. Currently the grid CO2 intensity in our region is 85g/kWh so 20g/kWh of heat energy. Gas is about 180g/kWh, so nearly 10 times the CO2 emissions.

Homely's been mentioned before on this forum. Unfortunately it seems to rely on an internet connection, which rules it out from my POV. It's probably a good idea for installers / customers who don't want to fiddle / don't understand how to set a system up.

Ours is what I would describe as an American fridge - 2 full height doors. Although a real American fridge would probably be twice the size!

When we moved to this house the swimming pool had an ASHP built into a brick built shed. The exhaust faced was about 3 inches from a big hole ine the wall. There was no baffle to prevent air bypassing, but it was so close to the wall that air flow was restricted. It seemed to work OK, but it won't really solve any noise issues. If you have a big enough hole for the airflow most of the noise will go out of the hole too. The ASHP we used to replace the original is fitted behind the pump house and is a lot quieter than the original, even though it is external. I have been quite disappointed by the noise that the recently installed ASHP for the central heating makes. I had been expecting something like the You Tube videos which seems to be pretty much white noise (which the pool heat pump produces) but the compressor is pitched and very audible and annoying. The absolute level is within spec and isn't loud enough to be a problem for the neighbours, but it doesn't half irritate me and I lived in a house close to a heat pump like that I would be complaining.

Our fridge freezer uses 260W for about 25 minutes to defrost, but it does it when it needs it which is about once a day but not on a fixed schedule. It's a possibility but several hundred watts for an hour or so sounds a lot for a fridge. if it is the FF I'd consider getting a more efficient one.

AIUI, but I could be wrong, eco only uses the heat pump, standard will use an immersion heater to top up, if you have one. Mine's set to 48C and comes on in the morning and afternoon for about a 50 minute window. Takes about 30 minutes to reheat.

+ 1. There were one or 2 similar buildings in the suburb I lived in when I was young which had definitely been air raid shelters. There's a WW2 pill box next to a canal near us of the same sort of construction, but octagonal. I think it has some sort of protection, may be listed. It's in a conservation area.

Yes, but those Brobdingnagian amounts are hypothetical; not available for home improvement until realised by selling the house. As an ex colleague of mine, who owned a house with a Thames frontage and a boathouse used to say "asset rich, cash poor".