That's really useful and has been a puzzle for us (ironically) as we used to run the Air to Air heat pumps (Panasonic inverting air units) like you do: turning them on in the morning and boosting the temperature with Gas central heating. So we tried for a year with just leaving them on (Jan to Jan) and to see how they run then. We felt that there was a saving, mainly as they got the house to a reasonable temperature overnight at the 7.5p/kWh rates and we don't have a battery system to make use of this rate energy during the day. Effectively we were using the house as a thermal store as the heating during the 32p/kWh day was less as a result (higher daytime temperatures and more light for the PV Solar) and the gas heating was greatly reduced. 2 things are changing, though, so this video couldn't have come at a better time: - We've added door curtains to the front and back doors. There is now a considerable reduction in thermal gradient as you walk along the 30foot corridor to the front door. It could drop as much as 5°C along it. uPVC doors are great, but don't expect an inch and a half of door to operate as well as a foot and a half of brick, rock-wool insulation and plasterboard. The wooden back door with dog-flap in was worse. - We're coming off the overnight cheap rate at the end of the month. Octopus provided a great summary of how we use energy: 3MWh off peak, 5MWh on peak in 2022. That's with the ASHP, EVs and washing going on overnight, so the maximum we can shift. With this information we could see that shifting to overnight usage and all the hassle of it will save us about 5% of costs if no other factors are taken into account if we go onto new Octopus GO at 42p peak, 12p off-peak, as opposed to a flat 24 hr 35p/kWh. Take increased solar use into account, and that 5% vanishes. So we're thinking of going back onto the variable rate. Prices are only going to drop, IMHO. Now add in this pertinent information about ASHP 24hr vs when needed, and that's the last piece of that puzzle: Only run them when needed (likely an hour before we get up). Many Thanks! Adrian.
About 7 years ago my mother had dementia and i found getting the house up to temperture in the cold morning was difficult. The reverse cycle heating ran flat out for about 6 hours to get the old house warm. If we left it on 24/7 it spent most the the time idling. the power actually came down using 24/7. Brilliant video as i had no actual figures but my wallet thanked me. The rooms we closed of that were not used, It was a alder house that was not the best insulated. If left of over night the house became very cold. Not a safe inviroment for a person with dementia.
All these housing apartments and smaller properties for the older generation could benfit hugely from these systems instead of the old brick radiators that don't really work. Wish we'd put this in for my mum years ago. So much potential
Really interesting as I’m a week into having our Fujitsu A2A system up and running. I’m still playing around with what works best here, so useful video to see how yours performed
I have 2 A2A units and find them sufficient to heat the house. On really cold nights I just have them ticking over on 19deg low fan and set the outdoor unit to night mode, very low noise. To be honest you can’t hear it standing next to it. Very economical to run even on for 24 hours. One averaged 11p per kilowatt. The main one was running at 18p per hour. Cheaper than the boiler and that’s been off since mid Jan. So pleased With the Fujitsu mini splits.
Thanks for this Nigel, interesting to hear how people heat their homes. It shows how futility of trying to compare gas / electric usage with other people unless you are like and like in; behaviours, components, building size and specs, heat loss and so on. This also makes an A2A to ASHP comparison skewed unless you are going to run an ASHP in the same way, shutting off rooms and so on. Although A2A units do produce a higher SCOP. Pros and cons with all systems and installations. I guess that's what makes the decision so tricky and it's expensive and time consuming to get it wrong. The key takeaway for me is that you are happy with your choice and it does what you want it to. Mission accomplished. This is the right system for your needs and lifestyle.
@John Tisbury now you have me confused...I thought A2A and ASHP were one and the same thing....what have I missed here please? New to all this but acutely aware we shall need to look into this for our property before very long.
@@judebrown4103 A2A blows hot or cold air from a unit mounted on the wall inside, there’s an outdoor unit which is the compressor. ASHP runs a traditional wet radiator setup or underfloor heating. Still has a compressor outside. Two different ways to heat and heat outputs; blown air and convection. A2A benefit from being able to do heating and cooling.
@@johntisbury ah excellent explanation, thank you so much. So that means you need a separate arrangement for making hot water with A2A I've just realised.... 🤔 I will look into it more thoroughly. 👍
Hi, I think Daikin have a solution that will do the air to air (heating and cooling) and also heat a hot water tank or a sunamp heat battery - not sure on the ins and outs but this does seem like the ideal solution if you have a small home. I think it's called the Daikin multi plus unit.@@judebrown4103
@@judebrown4103 Both systems are ASHPs one is air to water the other is Air to Air. We have air-to-air heating the house, and have turned off the gas and used the immersion instead - it works out cheaper because our ancient boiler's pilot light was using so much gas! After getting eye watering quotes for air-to-water from MCS installers, I'm now thinking of getting a new gas boiler to use just for the water. ASHP aren't so efficient when it comes to high temp hot water heating so it might make sense. MCS is an absolute joke.
More hot air from Nigel as usual...! ;-) Really interesting about the cost of logs, I bet most people don't realise that. I guess if you didn't have that massive battery then you could get similar rates with Octopus Cosy?
Similar but not as low I'm afraid. Burning logs can be a cheap form of additional heating but I'm finding heat pump, cheap rate energy usage is significantly cheaper
Good test. I do leave my heating on all the time. I found it uses less energy doing little top ups. As you know I have a ASHP with water tank and underfloor heating down stairs over 3 zones, oversize rads upstairs. Kitchen and living room kept at 21c, hall way 20c upstairs 20c. Heating has used 114kwh this month. Because the underfloor takes a long time to warm up whereas your air to air will be almost instant. Clear win for air to air. Especially for anyone after a replacement to their gas boiler. I guess I could do a timed test again, but as the warm up times take so long it is hard to predict how long the system will need to run before we get home etc. But I am a massive fan of underfloor heating and would miss it if I moved.
I run my ASHP the same. I've tried various ways but running 24/7 with a well optimised weather compensated temperature curve is the most economical for my house. With a low as possible flow temperature the underfloor heating stats are always calling for heat so the floor acts as the thermal store. We are on target to have reduced our electricity bill by 1000kWh per year compared to the first year we moved in when the ASHP settings were far from optimal and I was running a hybrid vehicle with a smaller battery!
I watch your videos with interest from Canada. What I’ve found with my 6 year old Fujitsu system is that temperature modulation in the winter takes too long to practically adjust temperature setpoints. Admittedly our weather is much more severe at its coldest, our coldest day this winter was -24 Celsius and one of our units cannot produce heat at that temperature. Our heatpump power consumption for that day was 75kWh, and the oil furnace kicked in to maintain the house at 17c. For context, our heatpump consumption for February was about 1000kw at about $0.17 CAD.
When you are relaxing in the evening is it more soothing to 'look' at the air conditioning units or the hypnotic flickering of wood on your wood burner, enjoying the health benefits of the infrared glow? Wood is more expensive if you have to buy it - but you only live once and if you don't have to decide between food or heat!
Very true but they do emit more emissions and particles that aren't good for us. I love our log fire and love burning things BUT I'm got to admit Im converting.
@@EVPuzzle A wood burner is 'enclosed' with your glass front and therefore and emissions of 2.5 particles is low. I would prefer this against the blown air from air heater which will help to circulate any particulates in the air heater itself. Blown air feels colder compared to radiant heat.
Thanks Nigel, so interesting to hear of your experiments - fantastic results for you - well done & thank you. 2 Quick questions: 1. Do you happen to know the EPC energy performance rating of your house, 2.: Any idea as to what you estimate the COP is during that cold week commencing 6th March? One final quick one - are you considering Octopus Flex?
I’ve found large spikes when the system is off for a period of time after turning it back on again so tend to keep it constant downstairs (underfloor 3 zones) and upstairs as well (radiators) although heat requirements are not as great up there. We are using more power this winter than last. A combination of off peak charging and perhaps having the heating on 24/7. It’ll get turned off completely soon until November 🤞and hopefully the battery will then help us compensate for that additional uses over the rest of the year.
i’ve got a 5kw ceiling cassette in a 500 sq-ft loft conversion (to the very latest insulation regs), it will heat the room up from around 13’c to 21’c in about an hour on a cold day. So it goes on at 8am and it’s ready for me to start work at 9am - so don’t see why i would want to run it 24x7
Thanks for sharing this information. It is really helpful. Having installed a similar system (6x Toshiba Haori 2.5kW + 2x Toshiba 8kW outdoor units) a couple of weeks ago, I am still trying to figure out the best heating pattern for our house. In your video you show your system ticking over at little over 300W and that got me thinking - I've never see our system even close to 300W. The lowest I have see our's when I have 3 of the indoor units and one outdoor unit on is around 900kW. Would you mind sharing what temperature and unit settings i.e. fan speed, eco mode, etc, do you normally use when running your indoor units. Thanks again for sharing these super informative videos.
As we've got fewer units it will of course run lower but we run in quiet fan mode a lot which keeps power below 1.3kw even in start up. For 300w we probably only have 2 x 3.5kw indoor units on, 300-500w is common once we're up to to temp with all three on. I find eco mode uses more energy strangely than quiet mode Power mode is set to 2 bars to reduce compressor load on startup but this doesn't impact watts use on tick over I find 19c setting delivers up to 21c room temp so might set to 20c then knock down to 19c when at temp we want With double the system setup you might expect double the consumption. Ive found our 8kw is plenty powerful if not too powerful for the 2 x 3.7kw and 1 x 2.7kw (10.1kw)Indoor units so your 2 x 8kw (16kw)units are beefy. Installers love matching up indoor and outdoor power but the bigger the outside unit, the more watts you'll consume at tickover
@@EVPuzzle Thanks so much for this info. I will give this a try and see how it goes. We have 3 indoor units installed downstairs in the living room, dining room and study respectively and 3 indoor units installed upstairs in 3 of the 4 bedrooms that we use. Hence the 2 outdoor units. I do find that they bring the rooms up to temperature from as low as 12C to 20C in under 30minutes. But that's when setting the target temp to 22C, power at 3 bars and fan at full speed. I'm still playing with the system to understand the best settings and usage for our house. This information definitely helps.
Great information thanks that coincides with what we found in using electrical heating and last winter with the gas heating what we used of it lol due to the prices of gas ! , I’ve asked this question lots of times is it cheaper to run heat pumps 24-7 and the geeks so yes but the owners say no like you Nigel and others if you got lots of storage and sun maybe but from grid it’s best to only heat the rooms your in . Ie it’s most efficient to not use energy when not needed! How many units do you have Nigel? We’re looking to get air 2 air if it’s hot again this summer otherwise use electrical heating this winter as now got extra batteries it’s go for gas free winter heating and if it’s only warm not super hot like 22 summer use ceiling fans and desk fans etc this year to save up for air to air for next summer.
Aircon in the house used to be an expensive luxury now it's a free added bonus when buying A2A for heating. Were about to remove more radiators and free up space on our rooms too
@@EVPuzzle yer it is great idea to get air to air over air to water just the cooling if we are to get lots of hot summers . And about getting rid of radiators is it worth it for the 2-3 inch you will gain ? Yes if you get rid of the boiler yes nice idea and make walls look better as can paint the whole wall etc but when you still got boiler ? I know your getting rid of oil boiler but is air to air without no other heating ie wood burning etc is air to air good enough on its own ? And I see I’m your video you used 14-15 kWh max in the cold snap but is that just your heating if so the rest of the home will use more than the remaining power in the batteries so you will be import at peak rate ? We have added another 8 kWh to our storage and by my maths on a normal winter day with limited solar just or maybe might have to lower heating use real cold days to get though till off peak ! And that 20.5 kWh nominal storage and about 18.5 ish usable would have liked more but £££ and current batteries won’t take more units but can always get third stack and new charger etc but were do you stop . Yes hopefully there will be enough sun most days to help like on my test was enough just were 2-4 kWh from the sun and wife goes to bed before me so that’s were I saved abit but got down to low Soc on couple of nights
Out of interest, how much is the A2A drawing while under heavy demand? I have GivEnergy batteries and their max draw is 3600w. I'd be interested to know how much I may encounter being taken from the grid on top of that
Many thanks for sharing your experience. How much of your house does the A-A heat pump heat? Also, is the unit noise in the house ever a nuisance? Thanks again.
Inside the house its be marginally better if the unit wasn't on the wall but no even overnight it's super quiet although defrost cycles woke me up once when - 4 outside. Our units heat all main areas of the house except kitchen and wet rooms. Leave doors open and more rooms are heated We've a large 4 bed house with study. 2 bedrooms and study closed off
I’m thinking that a2a is the way to go. I’d like to keep some of the radiators but remove our gas back-boiler. Did you say you have immersion heaters in your radiators? Searching online they are common in towel rails, less so in ordinary radiators but I don’t see why you couldn’t retro-fit them?
Exactly what I have done, 3 x 280w immersions. One radiator needs to be a little bigger in Cloakroom ideally, biggest bathroom might benefit from 400w immersion for faster heating but otherwise they're ideal. Warm dry towels and a warm room and smart controllable on smart switches. Perfect
Check out the Daikin systems, they have a version that is more discreet - panels fold away when not in use. They also have floor mounted units that might look better in some environments
Can you say please what temperature you have your house set to? Also when you said you were sweating what temperature was that? Wouldn't that mean the temperature was set too high so could have been turned down and the system achieve higher efficiency and run more continuously? With your comment about closing doors and not heating some rooms does your heat pump short cycle? Normally you design a system to heat the whole house so effectively making the house smaller makes the heat pump over-sized so has a tendency to short cycle which is less efficient. Conversely if it's not short cycling does it have the capacity to heat the whole house? Your energy use seems low but that might be due to lower set temperatures or high insulation. Energy input is balanced by loss in the end and in that respect all systems are equal.
Of course I can turn it down but that's the point, trying different things and see what fits. Anything above 19c in our bedroom is too warm for me. What we've learnt is there's enough power and heat whenever we want it
Robert That's a shame your is expensive. Have a friend on The Street with a heat pump in a big house and it's doing well it every house is different. First thing to check is how it's working. Put a monitor on the AC circuit perhaps to see if it's modulating too much, or should drop to a steady power use. I'd talking to the installer you'll need evidence of an issue otherwise you might just get," that's how it works" etc If it's just working hard all the time then a survey for heat loss might be next. Tbh that should've been done by the heat pump installer. Im not an expert by a long shot but in any problem solving you we'd data to undertand what's going on and why. Hope you have some luck improving it
Great video and useful information, I'm just waiting for the final quote for my whole house install (also Toshiba Haori) with 8 indoor units and 2 outdoor units, on of the externals can take up to 5 units so i may end up with 9 units overall. I have Oil heating at the moment so want to get rid of that as quickly as possible. My main question is how many internal units are you using and compared to the traditional radiator heating what do you think is the difference between starting the heating and feeling the benefit of the heat, is air 2 air quicker ? and the full control of temps and timings do you find that also adds to the effectiveness of the system overall
@@EVPuzzle I guess this where the amount of usage comes into effect if you can be out doing shopping etc and have the heating off and when you are approaching home just dial them on via the app then its service provided at the point of need. I use about 20kwh per day and expect during winter for that to double at least but I have the Cosy Tariff and Battery storage (12kwh but adding another 5kwh pylontech to the array) so should be able to offset a lot of the cost but as I was spending nearly £2k on Oil for heating then I think im going to still have savings. After two years of solar and battery I have only had to pay for 55% of my electric bill for the year which is a great saving and I know I can really improve that even more with a better Hot water solution and no more electric showers
You might want to look at how long the runs are going to be. Larger units are comparatively less efficient. I do have a 7.1KW unit it heats the ground floor without a problem and we rarely use the smaller units in the bedrooms. I hope you have obtained planning permission.
@@bobbazley5376 Nope. Any heat pump which can cool need PP there is no exemption. That is the Planning rules. I wish the planning rules would be simplified.
All the data points to the A2A being a about 25% better than ASHP to radiators. the SCOP and COP alone shows this as the difference. The only issue is DHW and that can be addressed in a number of different ways, for me getting an all in one Hot water cylinder with a built in ASHP will help make that much more efficient.
Not at all. Well apart from the defrost cycle when -4c outside, one cycle woke me up but it the Mrs, I'm a light sleeper. Units are so quiet you can't hear them at all in quiet mode of you have any other ambient noises or TV on etc
Our Panasonic Inverting Aircon units (1 external unit, 2 internal units) are now 16 years old and barely noticeable. The only time I really noticed one of them was during a Facetime call home and I could hear the low-level drone in the background as the TV was off. And that's kind of the point: unless you're sensitive to that kind of longitudinal rotating fan noise (some like it), almost anything else will be louder than it: the TV, Radio, dog snoring, etc. So yes, you can hear them, but no, after almost an entire winter of on 24/7, they're barely noticeable. for us.
@@MrTytalus Glad to hear. I bought panasonic HZ35 for my mothers 60sqm old apartment. Might be to big for that space. But better biger than to small. 😅
Given that at absolute max you don't come close to emptying your battery, do you think you've overspecced it? What do you think you'd actually get away with?
A slightly unfair comparison given you had a house that was too hot with it on 24/7. A better test would be to include a graph of the room temperatures for each room and have the units set to maintain an ideal temperature in each room for when the room is in use, and then have a lower set temperature when they are not. Worth noting with Multi-splits, that it's only the outdoor unit that needs to be on all the time to run more efficiently, so to keep it on, only 1 of the indoor unit needs to be on at a given time to achieve that. So you might find that staggering which one is on at a given point works out cheaper. One caveat though, is if your house or rooms are working fine as a thermal battery for 16 hours a day, and are comfortable, then your on/off strategy may be better than leaving them on 24/7.
Can anyone help, I am convinced that air to air heat pumps are the solution for an all electric house. But trying to search for an installer is a nightmare - most searches end up about water heaters or boilers as they think you want air to water heat pump or searching for air conditioning it all about cooling. Can anyone suggest a good national website that knows what an air to air heat pump is that gives heating and cooling. Nigel’s system sound just right for me.
@@colinwilkinson2811 Best to ring round a few of those Air Conditioning installers, Air 2 Air heat pumps are essentially Air Conditioning units with a few extra bits that allows them to run in reverse. And the installation method is identical.
@@colinwilkinson2811 ignite heating and cooling who installed the EV puzzle’s system came and installed mine and I am quite local to you (Berkhamsted).
Of course it's not pointless, you will have improved comfort in the house without cold dips when the heat is off. Why is your house warmer when running the heat for longer anyway. Were you not running it long enough to reach target temperature?
@@EVPuzzle surely the point of having a thermostat is that it doesn't get hotter if you leave it on for longer? The theory that we want to test is whether it is noticeably more efficient to spread the same amount of energy over a longer period.
No, In theory keeping the compressor to lower power should make it last longer but I guess using anything for more hours must put wear and tear on it somehow
Definitely won't hurt but I'm hearing loads of people just leave them and they're robust. It's reassuring either way but I'll be maintaining mine correctly
@@EVPuzzle Aircon units are a lot more reliable than the upstart ASHP as mostly offices used Aircon units for cooling but also heating in the most efficient way. The tech in these units is just more tried and tested and designed to be used on a daily basis for most of the day.
I usually love the data you provide, but random use of your log burner and open fire makes your test results inconclusive. Would have been really good if you had only used you air to air system. Also you say only rooms you are using are kept warm, more information on the size of the spaces being heated would be great!
The log burner will be adding pollution to your home too, each time you open the door to add another harmful particulates will escape. These are linked to lung disease, heart attacks, strokes and dementia. But in addition prevents your neighbours children's lungs from developing, linked to lower lung volumes and developing asthma or COPD. They don't get a say in whether people burn solid fuels but suffer the consequences. Sorry, very holier than thou but it's an important issue. It's traditional, cosy and had a greenwashing push recently but it's in truth awful for people and the planet. Edit The A2A looks great, I was quoted £18k for a system for my 5 bed house and I struggled to sign up, but might be the right option. Did I hear you quote a SCOP figure?
That's really useful and has been a puzzle for us (ironically) as we used to run the Air to Air heat pumps (Panasonic inverting air units) like you do: turning them on in the morning and boosting the temperature with Gas central heating. So we tried for a year with just leaving them on (Jan to Jan) and to see how they run then. We felt that there was a saving, mainly as they got the house to a reasonable temperature overnight at the 7.5p/kWh rates and we don't have a battery system to make use of this rate energy during the day. Effectively we were using the house as a thermal store as the heating during the 32p/kWh day was less as a result (higher daytime temperatures and more light for the PV Solar) and the gas heating was greatly reduced.
2 things are changing, though, so this video couldn't have come at a better time:
- We've added door curtains to the front and back doors. There is now a considerable reduction in thermal gradient as you walk along the 30foot corridor to the front door. It could drop as much as 5°C along it. uPVC doors are great, but don't expect an inch and a half of door to operate as well as a foot and a half of brick, rock-wool insulation and plasterboard. The wooden back door with dog-flap in was worse.
- We're coming off the overnight cheap rate at the end of the month. Octopus provided a great summary of how we use energy: 3MWh off peak, 5MWh on peak in 2022. That's with the ASHP, EVs and washing going on overnight, so the maximum we can shift. With this information we could see that shifting to overnight usage and all the hassle of it will save us about 5% of costs if no other factors are taken into account if we go onto new Octopus GO at 42p peak, 12p off-peak, as opposed to a flat 24 hr 35p/kWh. Take increased solar use into account, and that 5% vanishes. So we're thinking of going back onto the variable rate. Prices are only going to drop, IMHO.
Now add in this pertinent information about ASHP 24hr vs when needed, and that's the last piece of that puzzle: Only run them when needed (likely an hour before we get up).
Many Thanks!
Adrian.
About 7 years ago my mother had dementia and i found getting the house up to temperture in the cold morning was difficult. The reverse cycle heating ran flat out for about 6 hours to get the old house warm. If we left it on 24/7 it spent most the the time idling. the power actually came down using 24/7. Brilliant video as i had no actual figures but my wallet thanked me. The rooms we closed of that were not used, It was a alder house that was not the best insulated. If left of over night the house became very cold. Not a safe inviroment for a person with dementia.
All these housing apartments and smaller properties for the older generation could benfit hugely from these systems instead of the old brick radiators that don't really work. Wish we'd put this in for my mum years ago.
So much potential
Really interesting as I’m a week into having our Fujitsu A2A system up and running. I’m still playing around with what works best here, so useful video to see how yours performed
I have 2 A2A units and find them sufficient to heat the house. On really cold nights I just have them ticking over on 19deg low fan and set the outdoor unit to night mode, very low noise. To be honest you can’t hear it standing next to it. Very economical to run even on for 24 hours. One averaged 11p per kilowatt. The main one was running at 18p per hour. Cheaper than the boiler and that’s been off since mid Jan. So pleased With the Fujitsu mini splits.
Thanks, Nigel! This was interesting, as usual.
Thanks for this Nigel, interesting to hear how people heat their homes. It shows how futility of trying to compare gas / electric usage with other people unless you are like and like in; behaviours, components, building size and specs, heat loss and so on. This also makes an A2A to ASHP comparison skewed unless you are going to run an ASHP in the same way, shutting off rooms and so on. Although A2A units do produce a higher SCOP. Pros and cons with all systems and installations. I guess that's what makes the decision so tricky and it's expensive and time consuming to get it wrong.
The key takeaway for me is that you are happy with your choice and it does what you want it to. Mission accomplished. This is the right system for your needs and lifestyle.
@John Tisbury now you have me confused...I thought A2A and ASHP were one and the same thing....what have I missed here please? New to all this but acutely aware we shall need to look into this for our property before very long.
@@judebrown4103 A2A blows hot or cold air from a unit mounted on the wall inside, there’s an outdoor unit which is the compressor. ASHP runs a traditional wet radiator setup or underfloor heating. Still has a compressor outside. Two different ways to heat and heat outputs; blown air and convection. A2A benefit from being able to do heating and cooling.
@@johntisbury ah excellent explanation, thank you so much. So that means you need a separate arrangement for making hot water with A2A I've just realised.... 🤔 I will look into it more thoroughly. 👍
Hi, I think Daikin have a solution that will do the air to air (heating and cooling) and also heat a hot water tank or a sunamp heat battery - not sure on the ins and outs but this does seem like the ideal solution if you have a small home. I think it's called the Daikin multi plus unit.@@judebrown4103
@@judebrown4103 Both systems are ASHPs one is air to water the other is Air to Air. We have air-to-air heating the house, and have turned off the gas and used the immersion instead - it works out cheaper because our ancient boiler's pilot light was using so much gas! After getting eye watering quotes for air-to-water from MCS installers, I'm now thinking of getting a new gas boiler to use just for the water. ASHP aren't so efficient when it comes to high temp hot water heating so it might make sense. MCS is an absolute joke.
More hot air from Nigel as usual...! ;-) Really interesting about the cost of logs, I bet most people don't realise that. I guess if you didn't have that massive battery then you could get similar rates with Octopus Cosy?
Similar but not as low I'm afraid. Burning logs can be a cheap form of additional heating but I'm finding heat pump, cheap rate energy usage is significantly cheaper
Good test. I do leave my heating on all the time. I found it uses less energy doing little top ups. As you know I have a ASHP with water tank and underfloor heating down stairs over 3 zones, oversize rads upstairs. Kitchen and living room kept at 21c, hall way 20c upstairs 20c. Heating has used 114kwh this month. Because the underfloor takes a long time to warm up whereas your air to air will be almost instant. Clear win for air to air. Especially for anyone after a replacement to their gas boiler. I guess I could do a timed test again, but as the warm up times take so long it is hard to predict how long the system will need to run before we get home etc. But I am a massive fan of underfloor heating and would miss it if I moved.
I run my ASHP the same. I've tried various ways but running 24/7 with a well optimised weather compensated temperature curve is the most economical for my house. With a low as possible flow temperature the underfloor heating stats are always calling for heat so the floor acts as the thermal store.
We are on target to have reduced our electricity bill by 1000kWh per year compared to the first year we moved in when the ASHP settings were far from optimal and I was running a hybrid vehicle with a smaller battery!
I watch your videos with interest from Canada. What I’ve found with my 6 year old Fujitsu system is that temperature modulation in the winter takes too long to practically adjust temperature setpoints. Admittedly our weather is much more severe at its coldest, our coldest day this winter was -24 Celsius and one of our units cannot produce heat at that temperature. Our heatpump power consumption for that day was 75kWh, and the oil furnace kicked in to maintain the house at 17c. For context, our heatpump consumption for February was about 1000kw at about $0.17 CAD.
When you are relaxing in the evening is it more soothing to 'look' at the air conditioning units or the hypnotic flickering of wood on your wood burner, enjoying the health benefits of the infrared glow? Wood is more expensive if you have to buy it - but you only live once and if you don't have to decide between food or heat!
Very true but they do emit more emissions and particles that aren't good for us. I love our log fire and love burning things BUT I'm got to admit Im converting.
@@EVPuzzle A wood burner is 'enclosed' with your glass front and therefore and emissions of 2.5 particles is low.
I would prefer this against the blown air from air heater which will help to circulate any particulates in the air heater itself.
Blown air feels colder compared to radiant heat.
Thanks Nigel, so interesting to hear of your experiments - fantastic results for you - well done & thank you.
2 Quick questions: 1. Do you happen to know the EPC energy performance rating of your house, 2.: Any idea as to what you estimate the COP is during that cold week commencing 6th March?
One final quick one - are you considering Octopus Flex?
I’ve found large spikes when the system is off for a period of time after turning it back on again so tend to keep it constant downstairs (underfloor 3 zones) and upstairs as well (radiators) although heat requirements are not as great up there.
We are using more power this winter than last. A combination of off peak charging and perhaps having the heating on 24/7.
It’ll get turned off completely soon until November 🤞and hopefully the battery will then help us compensate for that additional uses over the rest of the year.
With our A2A, there are eco and quiet modes a d three power levels to keep peaks very small when restarting. Lots of flexibility
Very interesting mate. Cheers
i’ve got a 5kw ceiling cassette in a 500 sq-ft loft conversion (to the very latest insulation regs), it will heat the room up from around 13’c to 21’c in about an hour on a cold day. So it goes on at 8am and it’s ready for me to start work at 9am - so don’t see why i would want to run it 24x7
My experiment shows an increase of 30% when leaving the A2A heatpump on 24/7
How good is your house insulated?
Thanks for sharing this information. It is really helpful. Having installed a similar system (6x Toshiba Haori 2.5kW + 2x Toshiba 8kW outdoor units) a couple of weeks ago, I am still trying to figure out the best heating pattern for our house. In your video you show your system ticking over at little over 300W and that got me thinking - I've never see our system even close to 300W. The lowest I have see our's when I have 3 of the indoor units and one outdoor unit on is around 900kW. Would you mind sharing what temperature and unit settings i.e. fan speed, eco mode, etc, do you normally use when running your indoor units. Thanks again for sharing these super informative videos.
As we've got fewer units it will of course run lower but we run in quiet fan mode a lot which keeps power below 1.3kw even in start up. For 300w we probably only have 2 x 3.5kw indoor units on, 300-500w is common once we're up to to temp with all three on.
I find eco mode uses more energy strangely than quiet mode
Power mode is set to 2 bars to reduce compressor load on startup but this doesn't impact watts use on tick over
I find 19c setting delivers up to 21c room temp so might set to 20c then knock down to 19c when at temp we want
With double the system setup you might expect double the consumption.
Ive found our 8kw is plenty powerful if not too powerful for the 2 x 3.7kw and 1 x 2.7kw (10.1kw)Indoor units so your 2 x 8kw (16kw)units are beefy. Installers love matching up indoor and outdoor power but the bigger the outside unit, the more watts you'll consume at tickover
@@EVPuzzle Thanks so much for this info. I will give this a try and see how it goes.
We have 3 indoor units installed downstairs in the living room, dining room and study respectively and 3 indoor units installed upstairs in 3 of the 4 bedrooms that we use. Hence the 2 outdoor units. I do find that they bring the rooms up to temperature from as low as 12C to 20C in under 30minutes. But that's when setting the target temp to 22C, power at 3 bars and fan at full speed. I'm still playing with the system to understand the best settings and usage for our house. This information definitely helps.
Great information thanks that coincides with what we found in using electrical heating and last winter with the gas heating what we used of it lol due to the prices of gas ! , I’ve asked this question lots of times is it cheaper to run heat pumps 24-7 and the geeks so yes but the owners say no like you Nigel and others if you got lots of storage and sun maybe but from grid it’s best to only heat the rooms your in . Ie it’s most efficient to not use energy when not needed! How many units do you have Nigel? We’re looking to get air 2 air if it’s hot again this summer otherwise use electrical heating this winter as now got extra batteries it’s go for gas free winter heating and if it’s only warm not super hot like 22 summer use ceiling fans and desk fans etc this year to save up for air to air for next summer.
Aircon in the house used to be an expensive luxury now it's a free added bonus when buying A2A for heating.
Were about to remove more radiators and free up space on our rooms too
@@EVPuzzle yer it is great idea to get air to air over air to water just the cooling if we are to get lots of hot summers . And about getting rid of radiators is it worth it for the 2-3 inch you will gain ? Yes if you get rid of the boiler yes nice idea and make walls look better as can paint the whole wall etc but when you still got boiler ? I know your getting rid of oil boiler but is air to air without no other heating ie wood burning etc is air to air good enough on its own ? And I see I’m your video you used 14-15 kWh max in the cold snap but is that just your heating if so the rest of the home will use more than the remaining power in the batteries so you will be import at peak rate ? We have added another 8 kWh to our storage and by my maths on a normal winter day with limited solar just or maybe might have to lower heating use real cold days to get though till off peak ! And that 20.5 kWh nominal storage and about 18.5 ish usable would have liked more but £££ and current batteries won’t take more units but can always get third stack and new charger etc but were do you stop . Yes hopefully there will be enough sun most days to help like on my test was enough just were 2-4 kWh from the sun and wife goes to bed before me so that’s were I saved abit but got down to low Soc on couple of nights
Out of interest, how much is the A2A drawing while under heavy demand? I have GivEnergy batteries and their max draw is 3600w. I'd be interested to know how much I may encounter being taken from the grid on top of that
Interesting insight but not sure what happened to the starting video quality! Didn’t affect the content though…
It was shotand edited in 1080p so might be blooming TH-cam
Many thanks for sharing your experience.
How much of your house does the A-A heat pump heat?
Also, is the unit noise in the house ever a nuisance? Thanks again.
Inside the house its be marginally better if the unit wasn't on the wall but no even overnight it's super quiet although defrost cycles woke me up once when - 4 outside.
Our units heat all main areas of the house except kitchen and wet rooms.
Leave doors open and more rooms are heated
We've a large 4 bed house with study. 2 bedrooms and study closed off
I’m thinking that a2a is the way to go. I’d like to keep some of the radiators but remove our gas back-boiler. Did you say you have immersion heaters in your radiators? Searching online they are common in towel rails, less so in ordinary radiators but I don’t see why you couldn’t retro-fit them?
Exactly what I have done, 3 x 280w immersions.
One radiator needs to be a little bigger in Cloakroom ideally, biggest bathroom might benefit from 400w immersion for faster heating but otherwise they're ideal. Warm dry towels and a warm room and smart controllable on smart switches. Perfect
@@EVPuzzle brilliant thanks.
I’d like to get the same heating system as you but my wife thinks the indoor parts look huge up by the ceiling
Check out the Daikin systems, they have a version that is more discreet - panels fold away when not in use. They also have floor mounted units that might look better in some environments
Much smaller than a radiator on the wall
a bit, but one quickly gets used to them.
I got the daikin stylish, they are very neat and compact compared to most other models with the same output
Can you say please what temperature you have your house set to?
Also when you said you were sweating what temperature was that? Wouldn't that mean the temperature was set too high so could have been turned down and the system achieve higher efficiency and run more continuously?
With your comment about closing doors and not heating some rooms does your heat pump short cycle? Normally you design a system to heat the whole house so effectively making the house smaller makes the heat pump over-sized so has a tendency to short cycle which is less efficient. Conversely if it's not short cycling does it have the capacity to heat the whole house?
Your energy use seems low but that might be due to lower set temperatures or high insulation. Energy input is balanced by loss in the end and in that respect all systems are equal.
Of course I can turn it down but that's the point, trying different things and see what fits.
Anything above 19c in our bedroom is too warm for me.
What we've learnt is there's enough power and heat whenever we want it
@@EVPuzzle Yes. It's tricky comparing different systems when there are so many variables including people's comfortable temperatures etc
I'm in Old Costessey ,Norwich,
My air source Nibe is expensive.
I don't understand it .
I am A energy rating.
Can you help ?
Robert
That's a shame your is expensive. Have a friend on The Street with a heat pump in a big house and it's doing well it every house is different.
First thing to check is how it's working. Put a monitor on the AC circuit perhaps to see if it's modulating too much, or should drop to a steady power use.
I'd talking to the installer you'll need evidence of an issue otherwise you might just get," that's how it works" etc
If it's just working hard all the time then a survey for heat loss might be next. Tbh that should've been done by the heat pump installer.
Im not an expert by a long shot but in any problem solving you we'd data to undertand what's going on and why.
Hope you have some luck improving it
Great video and useful information, I'm just waiting for the final quote for my whole house install (also Toshiba Haori) with 8 indoor units and 2 outdoor units, on of the externals can take up to 5 units so i may end up with 9 units overall. I have Oil heating at the moment so want to get rid of that as quickly as possible. My main question is how many internal units are you using and compared to the traditional radiator heating what do you think is the difference between starting the heating and feeling the benefit of the heat, is air 2 air quicker ? and the full control of temps and timings do you find that also adds to the effectiveness of the system overall
Yes the flexibility is its advantage over radiator systems, it's instant when needed. I'm using 3 units in place of 6 large radiators, 2 in each room
@@EVPuzzle I guess this where the amount of usage comes into effect if you can be out doing shopping etc and have the heating off and when you are approaching home just dial them on via the app then its service provided at the point of need. I use about 20kwh per day and expect during winter for that to double at least but I have the Cosy Tariff and Battery storage (12kwh but adding another 5kwh pylontech to the array) so should be able to offset a lot of the cost but as I was spending nearly £2k on Oil for heating then I think im going to still have savings. After two years of solar and battery I have only had to pay for 55% of my electric bill for the year which is a great saving and I know I can really improve that even more with a better Hot water solution and no more electric showers
You might want to look at how long the runs are going to be. Larger units are comparatively less efficient. I do have a 7.1KW unit it heats the ground floor without a problem and we rarely use the smaller units in the bedrooms. I hope you have obtained planning permission.
@@jitheshappukutty3616 my understanding it its within permitted planning permission so I’ll not be applying for it.
@@bobbazley5376 Nope. Any heat pump which can cool need PP there is no exemption. That is the Planning rules. I wish the planning rules would be simplified.
Way better than the ASHP and radiators then!
All the data points to the A2A being a about 25% better than ASHP to radiators. the SCOP and COP alone shows this as the difference. The only issue is DHW and that can be addressed in a number of different ways, for me getting an all in one Hot water cylinder with a built in ASHP will help make that much more efficient.
How were the noise levels of the units inside the house? Although quiet did they eventually get on your nerves?..
Not at all. Well apart from the defrost cycle when -4c outside, one cycle woke me up but it the Mrs, I'm a light sleeper.
Units are so quiet you can't hear them at all in quiet mode of you have any other ambient noises or TV on etc
Our Panasonic Inverting Aircon units (1 external unit, 2 internal units) are now 16 years old and barely noticeable. The only time I really noticed one of them was during a Facetime call home and I could hear the low-level drone in the background as the TV was off. And that's kind of the point: unless you're sensitive to that kind of longitudinal rotating fan noise (some like it), almost anything else will be louder than it: the TV, Radio, dog snoring, etc.
So yes, you can hear them, but no, after almost an entire winter of on 24/7, they're barely noticeable. for us.
@@MrTytalus Glad to hear. I bought panasonic HZ35 for my mothers 60sqm old apartment. Might be to big for that space. But better biger than to small. 😅
Given that at absolute max you don't come close to emptying your battery, do you think you've overspecced it? What do you think you'd actually get away with?
Think I covered that in my battery design video, I added extra well beyond what's sensible or cost justifyable and have my reasons
A slightly unfair comparison given you had a house that was too hot with it on 24/7. A better test would be to include a graph of the room temperatures for each room and have the units set to maintain an ideal temperature in each room for when the room is in use, and then have a lower set temperature when they are not. Worth noting with Multi-splits, that it's only the outdoor unit that needs to be on all the time to run more efficiently, so to keep it on, only 1 of the indoor unit needs to be on at a given time to achieve that. So you might find that staggering which one is on at a given point works out cheaper. One caveat though, is if your house or rooms are working fine as a thermal battery for 16 hours a day, and are comfortable, then your on/off strategy may be better than leaving them on 24/7.
Can anyone help, I am convinced that air to air heat pumps are the solution for an all electric house. But trying to search for an installer is a nightmare - most searches end up about water heaters or boilers as they think you want air to water heat pump or searching for air conditioning it all about cooling. Can anyone suggest a good national website that knows what an air to air heat pump is that gives heating and cooling. Nigel’s system sound just right for me.
Where in the country are you? My Installer has started travelling further afield
@@EVPuzzle Hi Nigel, I live in Buckinghamshire High Wycombe
@@colinwilkinson2811 Best to ring round a few of those Air Conditioning installers, Air 2 Air heat pumps are essentially Air Conditioning units with a few extra bits that allows them to run in reverse. And the installation method is identical.
@@colinwilkinson2811 ignite heating and cooling who installed the EV puzzle’s system came and installed mine and I am quite local to you (Berkhamsted).
Details of my installer in the video description. He does travel.
Give Graham a call
I don't think it's really a fair comparison if your house was much warmer when the heating was on all day.
Lol but that's the impact of it being on for longer it was warmer. Its be pointless running it fur longer to achieve identical temps
Of course it's not pointless, you will have improved comfort in the house without cold dips when the heat is off. Why is your house warmer when running the heat for longer anyway. Were you not running it long enough to reach target temperature?
@@EVPuzzle surely the point of having a thermostat is that it doesn't get hotter if you leave it on for longer? The theory that we want to test is whether it is noticeably more efficient to spread the same amount of energy over a longer period.
Will the bearings wear out?
No, In theory keeping the compressor to lower power should make it last longer but I guess using anything for more hours must put wear and tear on it somehow
@@EVPuzzle keeping them maintained will obviously help with that ?
Definitely won't hurt but I'm hearing loads of people just leave them and they're robust. It's reassuring either way but I'll be maintaining mine correctly
@@EVPuzzle Aircon units are a lot more reliable than the upstart ASHP as mostly offices used Aircon units for cooling but also heating in the most efficient way. The tech in these units is just more tried and tested and designed to be used on a daily basis for most of the day.
I usually love the data you provide, but random use of your log burner and open fire makes your test results inconclusive. Would have been really good if you had only used you air to air system. Also you say only rooms you are using are kept warm, more information on the size of the spaces being heated would be great!
The log burner will be adding pollution to your home too, each time you open the door to add another harmful particulates will escape. These are linked to lung disease, heart attacks, strokes and dementia. But in addition prevents your neighbours children's lungs from developing, linked to lower lung volumes and developing asthma or COPD. They don't get a say in whether people burn solid fuels but suffer the consequences.
Sorry, very holier than thou but it's an important issue. It's traditional, cosy and had a greenwashing push recently but it's in truth awful for people and the planet.
Edit
The A2A looks great, I was quoted £18k for a system for my 5 bed house and I struggled to sign up, but might be the right option. Did I hear you quote a SCOP figure?
Seems like burning anything is bad.
To think fire was man's saviour