Toshiba Air to Air Heat pump (A2A) - Probably one of the best heating systems you can install

And it cools! These are air conditioning units but they heat brilliantly. Quiet, gentle, heating your home with incredible efficiency without radiators. No water leaks, no gurgling and no concerns about microbore pipes.
Heat Pumps are the future of heating but radiators aren't the only option
They're even cheaper to install than a water based heat pump solution.
Our system is a Toshiba 8kw Split system with 3 Haori indoor inverters
My aircon installer
Graham Durrant
Ignite heating and cooling
15 Connaught Ave, Gorleston-on-Sea, Great Yarmouth NR31 7LU
07989 610033
Email: [e-mail]
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Twitter: @EVPuzzle

[@easylikesundaymorning7340]

I'm an A/C engineer, I'm sick of telling people about this. The worst are the "internet readers" who think they know it all and start with .... "Heat pumps don't work when it's cold" and talk about their flow temps being too low etc etc. They think air to air is the same!! Well done that man for doing some proper research and doing the sensible thing. In my honest opinion air to air is far more sustainable than air to water.

[@EVPuzzle]

Glad to hear such an endorsement, there's so much more to A2A than people realise. Very positive experience so far. Imagine if new homes had it build in from scratch I stead of blooming pipes and radiators

[@zilspeed]

We have A2A too. Installed downstairs as a tester. We're installing upstairs soon and the gas boiler will soon be redundant.

[@lawsonspedding6136]

What temp do you set your heating at ?

[@easylikesundaymorning7340]

@@lawsonspedding6136 It depends on the individual, the thermal properties of the room and how you decide to use it. I normally recommend to customers that they try 21 as a starting place and go from there. Personally that's a little warm for me and I hover around the 19 mark but we are all different.

[@tlaroche38]

Had air to air in my house for 4 years and would never go back to a wet system

[@davidstorm4015]

Great choice, it's madness that air to air systems are not the norm in the UK. Blame the Government for not including them in the Renewable Heat Incentive some years ago. Low install costs, very economical, very reliable and has the bonus of cooling in the summer.

[@terra_incognita683]

Same thing for the Netherlands. I believe the reason there are no incentives for air source heatpumps is that they can also be used for cooling in summer and this consumes energy without solar panels.

[@GcS1515]

If the house has solar PV they should be included in the government schemes. It's just madness they don't. Your cooling would pretty much be for free if you have PV. High solar generation will certainly coincide with any use of cooling.

[@davidstorm4015]

@@GcS1515 I totally agree. We have solar PV and would have preferred an air to air system as they are much simpler and less prone to installation issues. I'm hoping that at some point we can ditch our air to water system and go to air to air instead

[@blobstrom]

I installed two Daikin heat pumps in my house in our living room and bedroom mainly for the chilling aspect quite a few years ago. I have been toying with the idea of fitting more and your video has certainly helped me direct my thoughts that way. Thanks

[@ShortVersion1]

Excited for you, congrats! Can't wait to see all your data observations. Hopefully next week, we will be swapping out our thermostat from an adapter-to-nest to the OEM Mitsubishi thermostat. I read in forums that the thermostat for the heat pump actually allows it to use VRF, but when we installed and opted for nest, it effectively crippled out system into a two-stage mode. Supposedly also forces it to defrost more frequently than it should. Even if we see a 5% reduction in energy with VRF, it should be significant in Winter.

[@mattheath7163]

Merry Christmas Nigel and Susan. Hope you have a lovely time.

[@jimmylaw7380]

Totally agree with your approach and also the requirement for a tidy cosmetic finish. The worst thing I dread is where the work done to your own house looks obviously retrofit. I would definitely pay more to get the job done with everything hidden as much as possible.

[@Barkster2]

I've had a Daikin system for a couple of years, in 3 rooms - absolutely brilliant. Heats the rooms in no time. Easy works at -5. Had a 4th unit put in the lounge in November, but something happened to the circuit board in the outdoor unit - 6 week wait for a warranty replacement. Not good if it's your only source of heating. Am having a Fischer electric radiator installed tomorrow in the hall (as I can't get an air handler in there anywhere). Also did the immersions in the towel rail radiators 6 months ago for warm towels in the summer ! Brilliant.

[@blackhoundrise8431]

The guy you found to do the install is a professional who cares. They have the right attitude. A rare find. Well done and thanks for sharing this update. 👍🏽🔥

[@ched999uk]

Great video, thanks. We are just investigating solar, battery and air to air heating/aircon. Great info, really helpful.

[@johntisbury]

Superb timing Nigel based on my tweet this morning about my dilemma over A2A and A2W systems. I'm swaying towards A2A and use the eddi / solar for hot water. Good to hear your experiences and the day to day use and feel for the heating. Good tips on the installation and siting too, you have indeed done your homework.

[@EVPuzzle]

Never perfect but thankfully taking our time and thinking it through has helped. May well add a 2nd system over time espevially if ducting to our bathrooms is possible

[@peteg8920]

We have had air to air heat pumps in Sweden for many years and they do make a difference to your energy bills. I would say that even the floor units have their advantages if you have room for them. Some people prefer to feel the warm air coming up from the floor . Having grown up in England I can imagine that they will work well as it does not get as cold as it does here, even though the houses are not as well insulated. The heat pumps are actually most effective with the fan on max if you can stand it. So put them on max a couple of hours before you get up and the house will be nice and warm.

[@markgilder9990]

I have a couple of mini splits. Works well, but struggled at -6c. But on a sunny day costs nothing to run off the solar. Installed the units myself. DIY ready to go units.

[@BenIsInSweden]

I love A2A heat pumps - I have a newly installed single "big brother" unit of yours, the Toshiba Daisenkai 9.5-35 (to replace an ageing Panasonic one), for my 5-bed house in Sweden. Previously I did look at either multi-splits or an A2W system, as there were 3 of us, with 4 out of 5 of the bedrooms in regular use. And the heating engineer did lean more towards recommending A2W, because one of the major drawbacks of A2A - especially with multiple units, is when it needs replacing you're replacing the whole system. With A2W, the rads/fan convectors, piping and storage tank all will live through multiple A2W heat pumps, so over time an A2W system will likely end up cheaper in certain situations, especially if most of the rooms are constantly in use. Now there are only 2 of us in the house, an A2W system is only really going to be likely to be cost-effective for a larger family. I will be reviewing how mine performs for cooling in summer, as previously I used a portable unit in summer for my home office and bedroom at night, and may look at getting a multi-split like the Haori for helping with the cooling in summer.

[@coolkiwi79]

Thanks for your post, I’m thinking about an A2A system for our house, but didn’t think about having to replace the whole system when the time comes, unlike an A2W system. Food for thought…

[@robsmith1a]

I was shocked by the quotes I received for a heat pump attached to my existing heating system. £11k after grant. Interesting to see what you opted for, looking forward to your long term report

[@bobjohnson7280]

When I was a kid (65 yrs ago), we had radiators that you could turn off if you wanted to. Of course, we also had knob-and-tube wiring as well. Now, I have air-to-air heating and A/C in Texas. Works well, unless the temps (deg F) get into the single digits.

[@nicdensley4104]

Thank you, adding more weight to my plan for air to air.

[@2251adamb]

Great content. Solar install is in the next month and now looking towards electric heating options and I'm mightily tempted by the a2a option.

[@USA-GreedyMenOfNoIntegrity]

I’ve used the factory line covers, pvc drain pipes, aluminum downspout slit up the back side and uv resistant tape. Whatever the customer prefers.

[@edwardpickering9006]

At least you got a quote from Octopus, wouldn't even look at our new build given it has microbore pipes everywhere... Clever use of the drainpipes! I think A2A works for partial/main room heating, would be tricky for the whole house. Be interesting to see how you get on with it...

[@philipbroggio9315]

Very interesting video Nigel. After six months with our Octopus installed Daikin system I am pleased to report that the design seems to have been about right. We had a 6.6kW requirement for a -2 day so a 7kW unit was installed in our 4 bed detached 128m2 house. Total cost was £6k after grant. When we got to the design day a couple of weeks ago we were able to turn our weather comp down to balance the system and get 20 degs downstairs and 18 upstairs. Original design was 50 degs flow but in reality we only need about 40. As to usage in first six months we have used around 917kWh of electricity to produce 3140kWh of energy but now that I have adjusted the weather compensation down we are getting higher values. Unlike you we are running with system on 24/7 but have a setback at night and kick system on around 4:30 to benefit from Octopus Go Faster rates. We are using the weather compensation to control the temperature not the thermostats as such so having the cold snap has allowed us to calibrate the curve. During the really cold days the worst daily usage was around 27kWh (generated heat 110kWh) and atm we are using about 10kWh. Definitely pleased to have ditched fossil fuels completely and the next stage is to get a battery to complete our setup . Keep the videos coming.

[@EVPuzzle]

Sounds good and a shame they wouldn't quote for the 7kw system here 136m2 home

[@paulwinters7679]

Did you have to get rid of your existing heating and hot water to qualify for a grant? Other you-tubers don't seem to have mentioned it..

[@MrButuz]

Told you air con was the way to go! So many benefits and so much cheaper to buy outright! If the Philips is as reliable as our Mitsubishi's have been you'll be happy for the next decade!

[@mikeynolan122]

Great video Nigel thanks worth the wait Our lg worked great at -5 outside

[@EVPuzzle]

Many thanks. Was holding back to get enough experience with it running in winter

[@ateeqn1985]

nice video.. in older homes if you leave heaters off for longer periods you may noitce leaks in the heating system.

[@CuriousDroid]

We have a similar system, a 3 way split with a Fujitsu 8Kw compressor and 3 x 2.5Kw indoor units plus 3 other single Fujitsu systems a 7, 5 and 4Kw, so 6 indoor units in all in a 5 bed house running from a 29Kwh plyontech battery and 8kw Solis hybrid invertor. It all works very well and very low power. We also found that on the very coldest days the power required by the heat pumps almost doubled but they have a COP of over 4 on typical 6-10C days in Essex, so that still a COP of 2 when its below 0C and days like that you cant count on two hands per year here by the coast. The only issue i have is that because we work from home and use computers all day, our base load per day is about 18-20Kw even in the summer with no heating or cooling so in the winter that goes up to about 30-35Khw per day. However, i can't charge the battery any more than 20kW on the 4 hour Octupus Go tariff, (4 hours @5Kw per hour). I'm waiting for Myenergi to make the Zappi charger Octopus Intelligent compatible so we can move to the 6 hour tariff. Once that happens i'll add another US5000 4.8kWh battery to the 6 we already have so i can store the maximum of 30kWh (usuable) which should get us through most winter days with little peak rate power. Once we get from March to September there will be much more solar power coming through the 8Kw solar and we shoud be almost self sufficient for 8 months of the year with plenty of excess for water and charging the car in the summer months.

[@KevinArmstrongUK]

We have gone for a Fujitsu system. 3x2kw downstairs and a ducted 4kw upstairs for 3 bedrooms. Can’t wait as using portable electric oil filled radiators currently.

[@EmyrEvans1]

Big fan of your channel! Hope you're on the mend now.

[@sjcsystems]

Just switch to IO and let the system auto charge once a month. Otherwise time lock it.

[@EVPuzzle]

Ducted into all the upstairs sounds good

[@tpottrell]

I spoke to Octopus about Intelligent recently and the guy said the Zappi is supported - it's that tne car itself needs to be supported too. At the moment there are only a few models that are...

[@Richardincancale]

I had a similar Daikin system in my apartment in Paris - almost 100m2 for heating and cooling, worked out about the same cost as with the gas at prices before the recent events… would be well cheaper now. As you say - when I was working at home I could just heat the one room during the day. Now on a bigger house with oil heating - 500 litres lasts about 2 months in winter, so looking forward to delivery of an air to water heat pump - delayed by supply chain issues :-(

[@AndrewEbling]

Super helpful video thanks - I've been looking at and thinking ASHP but even though our house and heating system are only 20 years old, there would still be a lot of work to bring the radiators and pipework up to spec. I also really like the idea of air con in the summer and the dehumidifier effect of AC for drying clothes without resorting to the tumble dryer on wet days. While I'd like to get rid of gas and loose the standing charge, I do wonder if air-to-air might be a good way to cut down reliance on gas, while also getting the cooling benefit in the summer.

[@gavinderbyshire5535]

I had a small 2.5kWh Samsung air to air unit installed for £650, it does daytime heating in the winter and cooling in the summer of our lounge, invaluable last year in the heat wave. Running costs are low and it's great for keeping the damp out.

[@imnothere220]

Thinking of same for a garden / off house office I am building. The heat in summer will likely kill me!

[@pumpkinhead456]

Thanks Nigel! I think you'd enjoy some Bluetooth thermometers around the house to keep track of your heating. I have 8 Govees, and know from experimenting that having my house at an average of 18 is achieved best by constant low heat - for me, timing 3 times a day is both more expensive and less comfortable.

[@richarddixon6354]

Great video, thanks, lots of things for me to consider. Looking at A2A in 2023 but hoping to get one that will heat my hot water. I believe Daikin are releasing something next year.

[@David-bl1bt]

Vaillant do a heatpump cylinder.

[@richarddixon6354]

@@David-bl1bt Thanks, I will have a look

[@MoreDataPlease]

Also look for the Dimplex EDEL. Air source heat pump cylinder. This is what I'm planning. For the technically interested - it has two volt-free contacts on the control board for PV mode, allows you to control heat pump only or heat pump + immersion if there's excess solar PV for example. I'm planning to use this and then control the thing using Shelly relays and Home Assistant. Would be interested to hear other users' experiences of Heat pump cylinders such as Vaillant AroStor and Dimplex edel. Also Daikin are launching a cylinder that can heat from an A2A multi-split port.

[@will3102]

Very helpful. I think people will gradually realise sticking a heat pump to radiators is madness. Most heat pumps in Europe are air to air

[@EVPuzzle]

Think it suits those that just want every room the same temp and like using radiators. Air to Air just sounds different and hence people are apprehensive. If these were installed as standard in new houses it'd be a massive improvement but radiators seem to be the way forward for most. It's in my nature to question and challenge things however

[@bilpat5123]

Definitely, where there are government grants there are over inflated prices...

[@paulos9304]

Not forgetting the shoddy, very shoddy workmanship that comes with grant work. That's fact

[@Chris-hy6jy]

Agreed, if the government is subsidising anything, you know it means back handers and middlemen creaming the hell out of it. If a system is genuinely good, it will sell itself. No need for grants!

[@bilpat5123]

@@paulos9304 true..

[@David-bl1bt]

Absolutely. All government schemes are a con.

[@EverydayLife621]

Well done nigel (&family), superstars - similar situation (with VE M+II + Pylon... ESS), albeit grade G house.... but its not that bad todate.... (using V2L MG4), overall similar not needed to use oil heating, so far. keep up the great leadership. BW J.&S.

[@davidwright1752]

Just place the units on out side walls the placement of the units is not critical hot air rises and cold air falls to the floor. So putting the unit in the hallway is not necessary. It may have been better in the kitchen. In very cold weather I found running 24 hours per day was cheaper than turning the units on and off. The inverter supplies just enough to keep a constant temperature. You have installed a very efficient unit. So if money is tight just 1 unit in the lounge room will do the job. Fantastic video very informative.

[@EVPuzzle]

Many thanks, we're over the moon. It's not just about reducing energy and saving money it's about providing better heat and more heat.

[@richardgore2000]

Again a balanced and sensible report.

[@givemethejob3293]

Merry Christmas Nigel, IMO could be one of your best yet! Well done for sticking to your guns with ducting, another industry which cannot wait to bank your cheque and get down the pub soonest.

[@philipgriffiths4222]

I have an a/c with air source heat pump (one room only) I am on a fixed rate of 20p KWh (Sept 2023), to give an example ran for 13.13 hours using only 2.46 KWh (below 0oC outside 14/12/2022) I am extremely pleased with results.

[@davidwright1752]

Fantastic result

[@GregoryNorris]

Thank you! Incredibly helpful video.

[@Erudite_Euro-Chav]

You sound like a very discerning customer !

[@ram64man]

having Air to water installed origonally spending thousands on underfloor heating was one of the biggest mistakes I ever made, after one buffero winter was enough electric was huge because of the temps often dipping into -10c for 3 months every 60 mins it was running a defrost cycle, so I called another installer to originally evaluate the install was correctly spec. after feeling cold for one winter we decided to add a twin 6 outlet unit air to air, 7kwh each two in the living room, (open plan) one in the den, an outlets linked to a in line air distribution feed to kitchen , and garden room, with the second feeding upstairs bedrooms and bathrooms, air to Air has been an absolute success, its been so good i disconnected the water unit, currently we are using 3kwh for the entire house an hour, on weather comp, compared to 10kwh for the underfloor water unit, right now were 3.2 to a kw, and the good thing the pipework was hidden in the old buildings air ducts that were seperated from the old furnace with an in duct unit typical in US heating, and across the crawl space in the lofts of the garage and main roof. the only water based heating unit that still on is for the driveway that's a must in these parts,. if you like air heating you can't go wrong with air to Air

[@EVPuzzle]

Wow underfloor heating sounds so appealling doesn't it but given the choice I'd go with A2A every day instead of water in pipes

[@mentality-monster]

Great video thanks nigel

[@michaelhounsome]

Great video Nigel really appreciate it, I feel I've hit the jackpot as this is exactly the same scenario i'm in with our 70's 4-bed detached which runs on oil, I've been pondering about air-to-water for some time but it just didn't make sense when you add the high installation costs and hikes in eclectic charges, i doubt it would save any money as I was being quoted of over 15k for install alone, it just didnt make sense retro fitting a air-to-water system to a house that was never designed for it and a hybrid ASHP/Boiler combo that would probably never work well together, i prefer the systems to be standalone and as they say keep it simple, the air-to-water retro systems also seem to average lower SCOPS also compared to A2A But like you we heat the whole house all the time and happy to have cold areas, it never gets above 19 degrees which i think is due to the fabric and block concreate floor and walls, it can feel like a cave (often warmer outside) but at least its cool in the summer, as insulated as it can be (cavity wall/new windows/doors/200mm rockwool in the loft). As we have moderate oil consumption 600-700liters per year its the gaps where the oil is off we struggle with, (ok now its warming up for summer) and would like an alternative heat source without the high install overheads, this seems like the right solution for us and my wallet, i dont know why the UK is so slow to catch on with A2A as they have been useing them across the globe for decades, with the added benefit of air-con, purification, dehumidification etc it really sounds a win-win. Love the Tosh system also, do you know how many indoor units this would support, struggling to find answers online, also how much you think this would cost to run on daytime tariffs only with battery storage in comparisons and are the savings worth the outlay on batteries, I'm new to this aspect so need educating please :) Thanks Mike

[@EVPuzzle]

I'll be doing a winter cost for heating video soon so, that should answer some of these things My 8kw inverter supports 4 split systems indoors but it is limited I think to a 40m pipe run. Good install design is needed

[@edc1569]

I prefer a2a with the low mounted console indoor units, make more sense in climates where you’re heating most of the time IMO

[@zyrtec455]

Almost every household in Thailand for HVAC is similar mini split air 2 air system as well. Drain pump should be your concern most pump broke before the life of AC about 5 years. When it leaks can be very problematic to walls and ceilings.

[@mikeroberts8412]

Superb thought provoking video, thank you. Just for interest: I have a 16kWh 48V LiFePo battery with an 11kW inverter. Charges from solar (4.8kWp) in summer and 4hr OctopusGo slot in winter. Provides pretty much all our power through the day on non solar days. We have gas for heating. I am considering a heat pump, so the kWh figures you provide are very useful in helping to direct my thinking. I will likely double my battery size first which will allow me to store around 28kWh overnight total in winter/0 solar day (150A at 48V for 4 hrs) which I think will be enough to power the heat pump on OctopusGo 7.5p (12p ish now) night rate based on some of your figures. I will take my time and do a full heat loss calc but my expectation is that I will likely go DIY with help from my local plumber and electrician. Once that is sorted then I'll add more solar of course! I suppose hot water would be heated from off peak electricity in winter and solar in summer so would use up some of that 28kWh budget. Just need to decide on A2A or A2W...Thanks again. Mike

[@philbattye]

Mike, you wouldn’t need to use any of your 28kWh for hot water. Just time it to use the low rate Octopus Go. Our 210 litre tank is warmed daily by about 1 to 2 hours running at 3kW.

[@mikeroberts8412]

@Phil Battye Thanks for the reply Phil, yes you're right but my 28kWh of energy is limited by the max charging current of 150A @ 48V for 4 hrs = 28.8kWh. Interesting that it only takes a couple of hours at 3kW, so 6kWh., that is useful info. Thanks again

[@allanhugh2044]

Very interesting development of your slow but inevitable move, to an all electric house. We are doing the same, although our 75 year old house, shabbily built in post war Australia (Melbourne), is nowhere near as energy efficient as your 15 year old house. We have insulated it reasonably well, but it is nowhere near what is the norm today. We too pondered whether to use a single multi head system, but eventually opted for individual units; all Mitsubishi Heavy Industries. 2kW units for the kitchen and main bedroom, 6kW for the lounge/dining/small office room, and a 3.5kW unit for our modern extension, which is well insulated. Total area is 142.8 square metres. Our kitchen unit is in the middle of the house, it too required some left of field thinking for the drainage. We too almost ended up with a pump arrangement, instead, solid pipe with a 15mm ID running at a 7º constant angle into our stormwater system, saved the day. Having single units enables us to heat/cool individual areas more efficiently than a multi-head large single unit, at least that was what our calculations suggested. Keep up the good work, greatly appreciated.

[@EVPuzzle]

Presumably you use it more more cooling than heating? If we were doing the whole house I think we'd have 3-4 outside units but so far it's doing the job nicely

[@allanhugh2044]

@@EVPuzzle Funnily enough, it is close to 50% of each, more so heating this year as it has been quite cool. But today has been a perfect Christmas day, not a cloud all day and hovering around 34º so two of the units were on keeping the inside between 24ºC to 25ºC on the parts of the house in use. Batteries were at 98% from around 14:00hrs (20kWh usable) all from solar 7.7kW of panels.

[@ecotts]

Ignite did a nice job from the sound of it.

[@EVPuzzle]

They were spot on. Very lucky to have found him

[@roncritchlow6793]

Thanks Nigel, great info.

[@tom95521]

We are having a 36 kBTU/3 ton/10.5 kW Daikin A2A 4 zone HP installed next week. We currently have a forced air natural gas heating system with a theoretical 30% heat loss in ductwork. We have 6.4 kW of solar panels on roof with grid tie back to utility but no battery. I hope we like our HP as much as you like your system.

[@EVPuzzle]

Be interesting to hear how you get on from gas heating air to electric . I suspect it'll feel nicer

[@richardsedorski1206]

Cracking vid marvelous information 👍👍👍

[@ndudman8]

Great points... and info, thanks

[@UrbanPlumbers]

bad installers want to do more than is actually required with A2W. We always size correctly and I would rather have a smaller heat pump with direct electric backup. A2A is cheap and easy to install, however, it is just a warm air blower in the end, and nowhere near as comfortable or quiet inside as a wet heating system. It also does not do hot water. You can just bolt on a heat pump to the existing system and I have done it. (Customers waiting to do upgrades at a later date when fully renovating) - efficiency though is not great, usually around 2.2-2.6 scop as opposed to 4.0-4.8 when done correctly.

[@marktiller1383]

A quility Japanese brand 7.1 reverse cycle air conditioning, costs about a 1000 quid, at Harvey Norman, with about another 300 quid installation in Australia. You can have a ducted full house AC unit. I have 2 smaller AC units one in the living room and the other in the main bedroom.

[@EVPuzzle]

Nice price

[@davidwright1752]

Mark is correct your prices in UK border on theft

[@davidwright1752]

On reflection you got a good price. However I only install separate units so 3 inside units and 3 condenser units that covers break downs. Most of the air conditioners now last 15 years or so. The inverter air conditioning are real game changer. The non inverter Units used to dim the lights when they turned on. So then soft starters were then added.

[@mikedennington8856]

if you only want to cool one room get a mobile ac unit. Many people heat the whole house and are heating empty unused rooms which baffles me. So your methodology is perfect, tailored to your needs.

[@EVPuzzle]

Very noisy and awkward to vent but we did this so a few years

[@Chris-hy6jy]

Having fitted a few of these systems in my own houses, I've managed to do it without ever using a condensate pump. They are definitely a weak part of the system so always try to design them out if at all possible.

[@carlfrancis8565]

Chris, interested to know what is the problem with condensate pumps? In other words, why are they a weakness?

[@Chris-hy6jy]

@@carlfrancis8565 as mentioned in the video, they make noise when operating. They can get blocked and the float can get stuck.

[@EVPuzzle]

Quality items though shouldn't be an issue m. Time will tell of course

[@givemethejob3293]

Seem to be replacing them at regular occasions at work, mini lime fit into trunking. Larger versions use perastaltic type pumps which seem more reliable.

[@Pulpdiction1999]

Some interesting thoughts and always useful to hear new ideas, I do think your video would be enhanced by actually giving a walking tour of the installs, the pipes, etc and the noise whilst running. I don't really get an appreciation of the size of the units from the photos, eye level video would be better. From the photos they look massive, perhaps this is just perspective.

[@EVPuzzle]

It is perspective so well done realising it. Video two will cover more detail of the units and operation. The install less so, it's just drilling holes and connecting power and pipes there's only so much I can say especially as I'm not an installer and don't want to cover the technical side of installing. It's not a DIY job and I'm not skilled to advise on it

[@lookoutleo]

I've been off for the second hand Fujitsu Siemens 6kw a2a heatpump second hand. I'm getting it fitted. What current does it draw on startup and once the system is up to temperature it tickover at, 600w is great. I'm same as you , I will watch like a hawk the wattage it uses. Think the one I'm getting is about 3kw max

[@myopenmind527]

Your challenge for 2023 should you choose to accept it is to make a video where you don’t say “I want”. Merry Christmas & Happy New Year!

[@jitheshak1]

Nice video giving a good overview and glad that the unit is helping you reduce your grid/oil usage. A few things to note, all the outdoor units will start off as quiet and become noisier as they age. Any A2A unit needs planning permission and are not permitted development. The text for PP has been changed subtly to remove any ambiguity. This whole PP can become an expensive money pit, when you need noise dampening covers, noise assessment etc. On the plus side - having a cool room during a heat wave is awesome!

[@sjcsystems]

Where is this as it’s the first I’ve heard of that?

[@nickieredshaw7835]

Yer very interesting to hear you need pp to fit a2a as not hear this from information I’ve been told ?

[@carlfrancis8565]

Thanks for this video, Fantastic food for thought and sounds like just what I need too! Q: No dehumidification on heating? Is there any option to ? Because dry air more comfortable and more efficient to heat. Q: Do you send dehumidification water to drain, or pump it to somewhere like the toilet cistern? After draining my dehumidifier to a bucket for more than a year, only thought of draining it to a potted plant for the 1st time this morning 😄 Q: does the same unit inside the house do both heating and air con, or are separate heating and air con units required?

[@ekrano]

Be great to see a basic schematic and some video of the installation.

[@EVPuzzle]

There a not much to see.. Drilling holes, fitting inverts on the wall, running cable and tiny pipe for gas then connecting it and gassing it up

[@sciencetestsubject]

Had a 4 kw 1 outdoor 2 indoor Mitsubishi a2a system installed last year. From looking at my own energy usage I saw I used the system 5% for cooling and 95% heating. Unfortunately my system is fairly undersized for my home (11 year old), I would probably need 6 kw. Normally I would use about 1500kwh in gas (including domestic hot water) for the month of December,. This year it has been reduced to an expected 130kwh in gas. When I looked at the Mitsubishi heavy industries catalogue it clearly says that on multi split you can connect up to 150% capacity of indoor units to 1 outdoor unit. My system for example has a 3,5 and a 2,0 kw indoor unit connected.

[@Benjamin-dx2wt]

Hi Erik. I am ready to pull the trigger on a mitsubishi hi system like you. I have reservations about the app it comes with and it's negative reviews. Do you use the app to monitor energy use and set schedules? Are you happy with what it offers?

[@sciencetestsubject]

@@Benjamin-dx2wt I unfortunately don't use the app at the moment, for my system it's an option.

[@Benjamin-dx2wt]

@@sciencetestsubject even better as getting no Wifi would make it cheaper. do you find the IR control enough for your control needs? also how do you measure your unit's energy usage?

[@sciencetestsubject]

@@Benjamin-dx2wt Ir remote has far more than I need and is very easy to operate. You can set a complete weekly program on just the remote. I measure energy consumption through a smart plug.

[@richardlincoln886]

Very interested in how you decided where to place internal units Discounting bathrooms I get - they go with electric elements in the radiators etc. For the rest of the rooms though/hall spaces? I just ran a test with 2x units (1.8kw and 2.5kw) in the main living space and home office and seems like extending to the rest of the house - esp. upstairs would be interesting. Separate air source hot water tank perhaps later as the final nail in the oil boiler's coffin.

[@rodden1953]

Thanks Nigel i think this is for me , im single im 71 spend most of my time in the livingroom, i would live to come off gas completely and just have the one bill . ii have a Powerwall v2 and 32 solar panels facing east south and west ( west dont really work in winter) . i dont really get any visitors and i sleep inn the livingroom out of choice, So far ive never gone on a night rate as im basically off grid with electric but i would go on a night rate if i only had the one bill . my house is a 3 bed semi concrete but with outside insulation , These companies dont really do an assessment for how people live it isnt one size fits all , i shall look into what you have done i didnt know you can use old wet radiators to be electric . Many thanks from Toby the dog on X . PS if i went on the night rate i wouldn't hhave to worry about charging the car in the winter its on the Zappi right now gettin 4kw from the sun . any advice is welcome.

[@EVPuzzle]

Sounds like you're similar to me , not wanting to heat all rooms all the time Sometimes with lots of solar it's great to indulge and turn everything up but it's a bit unnecessary so good to have flexibility . Plus Aircon in summer 😎 Heat pumps work best when loaded and left running so it's good not to over configure. We run 2 units at a fraction more energy than a single unit , 3 units use even less per unit . I'd be apprehensive of just a single unit . Itd work of course but why not heat more for a fraction more energy , 400w instead of 300w tick over A2A is also a very comfortable heat , filtered air too. Give Graham a call at ignite , he's great at figuring out solutions

[@rodden1953]

@@EVPuzzle Thanks Nigel i think id only need 3 livingroom hall maybe one upstairs. i shall look for ignite i live near Salisbury dont know if they travel this far but ill get intouch with them

[@rodden1953]

@@EVPuzzle Ive just been told the Grant isnt for A2A its the best for my needs .

[@EVPuzzle]

@@rodden1953 he travels all over , even in Wales !

[@rodden1953]

@@EVPuzzle Oh ok i have emailed him , Thanks i just hope they do the grant for A2A

[@wobby1516]

Interesting that you have fitted small Immersion heaters into your towel rails. We did the same over 3 years ago when we fitted our solar system. In our case I wired the two towel rails back to the Eddie’s 2nd zone and then when there’s spare solar the towel rails come on. It’s great in the summer months when there’s loads of solar, in the winter I use the timer function in Eddie to operate the towel rails as required. It meant a bit of extra wiring but now done it was worth the hassle. I’m very interested in you heating system my one concern is how well the heat pump works when the temperature is near or below zero. We have an Aircon in our kitchen that works well in cooling mode, is great for Dehumidification however in heating mode it only work well if the outside temp is 5 c or above, below that temp the outside unit freezes over. I’m a bit miffed that most companies don’t tell you that their equipment only works down to a certain temp for heating, they should be more up front about the performance of the equipment. Following your Vlog to the end I see that your units have a defrost mode and that’s were mine doesn’t. Fortunately I’ve just the one unit and I bought that mainly to cool the room in summer. Thanks for your brilliant Vlog it’s certainly got me thinking down a different route. Our ten year old house has plastic microbore pipework and that’s not a lot of use if we chose an air to water heat pump, it would involve a major work upgrading the pipe work and ripping up chipboard flooring, a nightmare.

[@EVPuzzle]

Yep our heating has worked fine so far down to - 6c outside. A few defrost cycles in the worst weather but heat has been fine I have heard placement of the heat pump can help, not too exposed

[@rodautechre]

Impressive low energy use for a 136m2 home, out of interest how much insulation do you have in your walls/floor/roof? Enjoy your regular vids very informative, thanks.

[@EVPuzzle]

Just standard Insulation atm Well add more to the loft later over bathrooms especially

[@st11gxavier71]

Could you share some photos of the heat pumps in their locations.

[@SabretoothBarnacle]

Great to hear this kind of advice! What square footage is your house and what percentage of that is heated/cooled with this new install?

[@EVPuzzle]

136m2 and probably two thirds heated

[@SabretoothBarnacle]

@@EVPuzzle Thank you

[@nickieredshaw7835]

Very interesting and informative but how much was the air to air system fitted like yours ?

[@johnbanks8065]

Glad to hear you found a solution that works for you 😊. I'm also considering an air to air system, but it would involve quite a long pipe run to get to a couple of the heater/cooler units, so I'm interested to hear that your installer had to be quite creative for one of your units; what was the approximate distance that he had to route the pipe including all the ups, downs and horizontals please?

[@EVPuzzle]

35metres approx adding it all up

[@johnbanks8065]

Cheers for that, it's good to know that such runs are possible @@EVPuzzle

[@IanWoolcock]

Shame the condensate pipes are an issue we are in a bungalow and if all the pipework could run up and through the loft these could be installed very easily and neatly. I see there are heat pump water tanks as well now which is a nice solution to the HW issue.

[@marcussmith6523]

For a bungalow the neatest way is ducted installed in the loft. No on wall units needed and condensate pipe is from the loft to outside.

[@IanWoolcock]

@@marcussmith6523 interesting thanks

[@EVPuzzle]

A good installer will sort the pipes but remember it's only for the awkward install areas, rest are easy and not an issue

[@nickieredshaw7835]

@@marcussmith6523sounds interesting is that the ceiling cassette your talking about here ? We have a 3 bedroom bungalow and looking to get some kind of heat pump installed just not decided which yet ? If we regularly get hot weather like this summer it will be air2air and would want as neat as possible install love the ideas of hidden pipes etc

[@Pinzpilot101]

I am lucky I have a large field and I will be having a ground system, buried below the field. Why have I gone for that....I live in eastern Poland it it gets too cold for Air Source.

[@sjcsystems]

Very interesting, but the video I just watched said...do not put the internal units up high, as that is the default for cooling. For heating, they should be down low.

[@EVPuzzle]

Depends how tall your room is I guess, I'm finding heating and cooling perfect with normal room heights

[@CT-vm4gf]

The vanes adjust to point down to throw the warm air along the floor.

[@GcS1515]

Ni Nigel I'm just about to go down the route of A2A with Haori units, have you tried integration with Home Assistant? I see some integrations on HACS for example, but would welcome confirmation that there is a working integration, especially from a UK system

[@EVPuzzle]

There is a working integration I've tried but it conflicts with the solaredge integration so I can only run one or the other. Hopefully one day the solaredge integration will be updated or the Toshiba one, whichever it needs. Its been an issue for a couple of years though

[@keithhobbs1]

Very interesting video. The phrase which always springs to mind when talking about heat pump cost is rip off. As I understand it the technology isn't all that different between air con and heat pumps? Or is the additional cost down to the changing radiators and piping and adding additional insulation I wonder.

[@Pierceb2]

Yes A/C Unit is basically the same as a Heat Pump. There is a reversing valve in a heat pump so you can use the refrigerant to either extract heat from the air in the house and dump it outside or extract ambient heat from outdoor air and dump it into the home. You should get a few quotes and ask the HVAC engineer for recommendations and a price quote. There can be multiple solutions that might work for your situation. In my State in the US we have a 10K rebate currently for Heat Pump Systems from the utility ( everyone pays $3 US each month to fund the energy conservation subsidy / rebate programs pool) for over 30 years now. Our programs require a Home Energy Audit which requires meeting minimum efficiency standards be met to get the rebates. If your air sealing or insulation falls short you can get 80% discount on materials and labor and they provide the contractor to do the work. They will also use infrared cameras to visualize heat loss etc. I am surprised that in the UK you get your government grants for these heat pumps no matter how well or bad the insulation of the home is. We also have non profit or consumer interest / energy efficiency advocacy groups who provide high level consultation, education, seminars, websites to help consumers out. It’s not perfect and you have to look into it and educate yourself. As for contractors / installers and their prices it’s the Wild West. We can also get 7 years interest free financing for the heat pump system which is net cost after 10k immediate subsidy. The moral hazard is the quotes can be inflated because it’s “free money” to some extent. The irony of all this is that many people don’t take advantage of these programs because they think “heat Pumps don’t work in cold weather”their neighbor got burnt by a bad install or contractor. Or they try to run the system on demand like they did with fossil fuel or they like their home like Miami Beach or Hawaii in the Northeast US when it is - 5 F one day a year or something like that.

[@Barry-xg1rd]

Great video Nigel! Just to clarify, is the minimum draw dictated by the size of the outdoor unit? For example, if you only had 1 indoor unit running the minimum draw may not be much less than having all 3 indoor units running? I was considering the larger 10kw outside unit to run 5 indoor units and cover the majority of the house. If this means the minimum draw would be higher even when running 1 or 2 units time we are likely to try and make do with 4 indoor units and go for the same outside you have. Hopefully this makes sense. Thanks

[@KevinArmstrongUK]

We have a Fujitsu 10kw outside unit and 4 internal units getting fitted next week. I’ve got my energy meter at the ready.

[@EVPuzzle]

That's my understanding yes, and what I saw in the toshiba data. Lower the outdoor unit capacity the lower the power used both at peak and minimum tick over.

[@neilcase]

I can see the benefit of this system and am thinking of installing one. However I don't see any mention of things like estimated lifespan of the system or ongoing maintenance costs (eg servicing). Can anyone shed any light on this? Being 'refrigeration' technology, I would expect it to be very reliable (like 25 years before breakdown - I wish), but these units are much bigger than a fridge compressor and there's all the fans too. Ta

[@RobinChapman]

Care re your AC drain pipes going into main down pipes from your roof. If they get blocked below the connection your AC drained water and excess rainwater could backup into your indoor units. Happened to me unfortunately. A bit messy.

[@EVPuzzle]

Good point, what's the option just drain to the ground?

[@USA-GreedyMenOfNoIntegrity]

Just keep your gutters and downspouts clean. No worries.

[@nickieredshaw7835]

Good point with moss and other bit’s could be a issue maybe use them net bits on the mouth of the guttering we had lots of issue with blocking guttering even with mesh on last house

[@shawn7336]

We have a situation. Midway through our renovation, with solar panels coming soon ish.. ASHP is probable, however there is no CH to plumb into and have a concrete floor.. so I like A2A, despite the lack of grant. BUT what to do about hot water?? This will be for a child’s daily bath and washing up. While all our ceilings are down I want to find answers fast. Can anyone help with ideas please?

[@EVPuzzle]

Mixergy tank, fill up on solar

[@johnh9449]

Did you get planning permission for the Air to Air system? Many people don't realise that an Air Source Heat Pump is only "permitted development" if it's for heating only. If it provides cooling it requires permission from the local authority. You also can't get the £5k BUS grant for an Air to Air. The reason is due to carbon reduction - an ASHP providing heating saves energy and carbon compared to a gas boiler but providing cooling consumes energy and carbon which a conventional boiler doesn't attempt. The above may change considering many people have solar PV to drive and negate the cooling energy and carbon consumption in summer which would otherwise come from the grid but that's the current situation.

[@paulgoffin8054]

How's it working at low temperatures, Nigel? The A2A units I've looked at don't appear to be rated below about 7C external temperature (which doesn't seem right). Did you get any really cold days? - Norfolk looked like it didn't get below about -2 over the last few weeks when it was a lot colder in the rest of the UK

[@KevinArmstrongUK]

That doesn’t sound right. The R32 systems I’ve looked at work to -15

[@KevinArmstrongUK]

I have my a2a scheduled for install on 4th Jan. Frustrating how the push (and grant) is for a wet ASHP. We had quotes of £8k and £11k (after grant) and loads of issues with old system to overcome. A2A system is £6k and a much simpler install. They should give the grant to anyone removing gas/oil and fitting renewable heating?

[@EmyrEvans1]

Agreed, absolutely.

[@SuperDiagnostic]

That won't happen as they will increase the overall carbon demand when used to cool in the summer.

[@illbeback2YT]

What about the ventilation side of the system? How does dirty air flow out of the house? Is there an energy recoverysystem involved? In my experience this aspect seems to be underestimated by some people here in the Netherlands.

[@EVPuzzle]

Nope no air recovery, open windows to vent air out 😂

[@SuperDiagnostic]

Great video again Nigel. With the internal units at head-height do you find a cold area at floor level; cold feet? What SCOP are you getting? Initially wanted wet ASHP with UFH for ground level but the cost is crazy and the running costs seemingly unknown; A2A seems to be a far superior product even without the grant. Only issue is distribution throughout the house.

[@EVPuzzle]

Not at all no, very well distributed

[@EVPuzzle]

Scop of 5 in summer, 3-4 in winter, 2 when -2 and below estimates from wattage used. No cold areas its toastie warm. Only loss is the heated floor areas from heating pipes under but floor. Longer we leave heating on warmer the floors get. Distribution around the house is excellent we can literally heat rooms on opposite side of the house turning fan speed up if needed, it's very controllable

[@SuperDiagnostic]

@@EVPuzzle Sounds great compared to the over-priced and over-specified wet system being offered. Happy New Year to you my friend 🍀

[@nickieredshaw7835]

The the grant for air to water and no grant for air to air seem about the same price for the quotes we got maybe were using the wrong company’s be interesting in others experiences of getting quotes for both were in a 40 year old 3 bedroom bungalow about 120 M sq area that’s fairly well insulated without micro bore and after watching a few KZbin videos found one chap that fitted theses units on two outside units for 5 indoor units like we would ideally want if going air air for best part of £9 k , if we are going to get summer weather like w3 had this year air conditioning of air to air would definitely be advantage but still on the fence to which to go with ,

[@molly5251]

Also you have had air source pump system fitted is that 6kw out put but does not use 6kw input, i am asking because i have all eclectic house with 31 panels on roof and garage with 25kw of batteries, but have a 12kw electric boiler

[@EVPuzzle]

Absolutely, 8kw heat output potential with 4:1 saving on energy typically

[@Rubbernut]

Good evening excellent video can you tell me did you need a pump for the condensation pipe for when it’s in cooling mode as you came from the loft, i’ve been pricing up and investigating the same system. The installer who priced mine up says I would need a pump at the side of the indoor unit because I’m coming down from the loft also , but I do not want to compromise the Asthetics of the unit.

[@EVPuzzle]

The mini pumps are hidden in the units or up in the loft using extension tubes. Not visible and can't be heard

[@Rubbernut]

@@EVPuzzle thank you for your reply

[@mark_just_mark]

One thing you mentioned was that the units are ‘high up’, if how air rises isn’t it better to position them lower down? Is the positioning based on ‘cooling’?

[@EVPuzzle]

Pipe runs are high up and they look better than a lower radiator style. Because air is pushed diwn by fans it really works well

[@mapryan]

Very surprised you didn’t mention the biggest single drawback. If it cools or you have more than one external unit you have to have planning permission.

[@adamdevine7375]

I knew about the 1m rule but not the 'if it can cool' rule. I wonder why the planning authority care about ability to cool? Given summer 2022 temperatures, a2a heat pumps are going to become a very popular option.

[@nickieredshaw7835]

O didn’t know that , we are near our neighbours on both side had lots of quotes and heat loss etc done few said about the units can’t be too near there windows etc but didn’t say anything about planning permission mite be necessary

[@MrButuz]

wut?

[@asilver2889]

How would you even know to seek this? Having just done a build, going through planning, conditions etc, I did not spot this. Also how would anyone know - just looks same as A2W heat pump from outside. They have to catch me first ....

[@EVPuzzle]

Out of date for sure, if needed it should be safe for ashp and boiler vents

[@molly5251]

Hi Couple of questions are you on cheap rate electric for night time to charge your batteries up on a night. Are you on fixed export tariff or octopus agile

[@EVPuzzle]

Octopus GO tariff, cheap from 230am to 630am. Referal link on the vid description

[@kalelkar]

I'm implementing a 3.5kw x4 in each rooms. What are the number of outdoor units to cope with this? Can I get one large mitsubishi rather than 2/3 separate ones? What are the benefits and drawbacks of this vs a getting a large kW unit outside?

[@efficientairconditioning]

I'm currently fitting a electriq 4 way split with a single outdoor unit, it runs off a 40amp fuse, they do a 5 which is a 40a also. The benefits for having single splits for me would be having different cycles in different rooms ie having one in heating and another on cooling, as with a muilt split they all have to work the same function, also if one breaksdown it won't effect the others. The downsides would be the amount of outdoor units around your property as air con (hot/cold) doesn't fall under the permitted development!!! The rules for heat pumps is 1m from your boundary and the first unit only a second would require planning. I've never known a problem as long as it's a single unit falling within the regs.

[@johnwilkins2023]

Thanks Nigel. Did you say your heating goes off around 6-7pm in the evening. Your house must be well insulated if it’s still comfortable to sit still 3-4 hours later.

[@EVPuzzle]

It's not like we're sitting up to midnight with blankets lol Only drops a degree maybe before we retire

[@USA-GreedyMenOfNoIntegrity]

No staying up past 10 PM much after 50🤣!

[@EVPuzzle]

Up at 5 instead

[@smallfatman7]

Does anyone have any experience with ducted air to air systems? Thanks

[@teranova5566]

4:57 Ok, finally some concrete number about heating the house. 500 to 600 liters of oil per year. That is exactly the same as diesel with specific energy 10.8 kWh/l, so that gives the worse case 6480 kWh/year energy use for heating. Comparing that to average energy use for household 12000 kWh/year that energy use is very LOW 👍 around 50% of typical use. That means the house is well insulated. Of course yearly electricity use is much higher than average.

[@teranova5566]

It would be good if you could measure now, the total electricity use by air heat pump and heaters this winter for comparison.

[@EmyrEvans1]

@@teranova5566 Extremely rough estimate - around 12 megawatts each winter, but divide this by 4 due to the SCOP and you end up with 3 Megatwatts. Remember you'll need to heat your water on top of this though.

[@EVPuzzle]

I do exactly that, every device is monitored seperately incl Toshiba units

[@Benjamin-dx2wt]

Did you find the Toshiba app useful? Does it enable to change all settings on the go, do schedules, overwrite it temporarily etc?

[@EVPuzzle]

Yes it does. I'll do a video on the detail of usage shortly..

[@Benjamin-dx2wt]

@@EVPuzzle Thank you for prompt reply. Only because we have to make a decision next week how would you rate it the app? 3/4 or even 5/5? And a last Y/N question: can you change all the settings in the app as with the remote?

[@brianm4789]

Hi, how programable are they... Could i have it maintaining a property at 19c, but then have them automatically in dry mode for 2 hrs each day ?

[@EVPuzzle]

You could but dry mode is actually air conditioning so heat it up then cool it down? You'd be better adding a separate dehumidifier as the heating up will be better in a drier atmosphere. Heating damp air isn't as effective as heating drier air With a split system they all have to be in the same mode , heating, cooling or just fan etc

[@RufusCubano]

What about the infrared panel you installed on the bathroom...completly ditch now? I was planning to test it out on my own. Ill appreciette your insights.

[@EVPuzzle]

Haven't turned it on in months, it's still there unused. Looks pretty being glass like a dark mirror but takes too long to do anything and doesn't warm the towels. Shame I bought three of them. I'll find a use one day

[@RufusCubano]

@@EVPuzzle I thought it was instant warmth, like the old radiators of the 70's...

[@EVPuzzle]

Not on the ones I've tried, admittedly they're only 350w and not ideally positioned

[@kevindavies4431]

Hi Nigel. We have just had the same system installed. Toshiba 10Kw Multi split outdoor unit with 1 x 3.5 an 3 x 2,5KW Haori indoor units. We have the units scheduled for most of the day at 21deg C, (heat setting only) and low fan. (Outside temp 0 deg). However this is generating very little heat! (Luke Warm). App is showing a 29deg room temp but it is only 18deg C actually measured temp. Can you recommend the best settings on the fan and or increasing the required temp to compensate? Also on the Energy Monitoring on the app has got the linear Graph consumption colours for each indoor unit wrongly allocated. Is this a bug in the App?

[@EVPuzzle]

When units aren't in use the high temp gas can distort what the actual internal temp is , you need some air flow to get it going . Just use auto and increase temp to get it going. It can be slow without increasing fan speed or temp. Only an issue when some units on and others off. It always sorts itself out eventually but I'm impatient so adjust temp and fan speed up for a few minutes

[@PlayerOne101.]

Did you research the outdoor/indoor units or just go off the installers advice. If you did research can you send make and model. I’ve got solar installed because of your videos and now looking at air to air. I’ve been told Mitsubishi are the most efficient

[@EVPuzzle]

There's not much between to be honest mitsubishi heavy industry are great apparently but Haier are great too as are LG etc I chose mine based on knowing how the App and Interface would work. Although they all work on remote control for me that is the contingency method of operation , I wanted online app, Alexa integration etc so I chose Toshiba . So far so good but do your research as you've got to live with them a long time Installer normally adds up indoor units to size the outdoor unit . In more a fan of working out your house heat loss value so you dont oversize My house heat loss number is just over 6kw so a 6kw unit should be enough . Installer recommended 10kw so I dropped to 8kw outside inverter for our 3.7+3.7+2.7 units The difference is how fast they'll heat your house but more importantly what wattage they tick over at when at temp . Bigger the unit , higher the tick over . 8kw is oversized for us ! But it means we run in eco lower power mode all the time

[@EmyrEvans1]

Thanks Nigel. Does the Toshiba App show what kind of S/COPs you're getting? And do you need to service the Hoari system annually? (Thinking of geting a very similar set up myself)

[@EVPuzzle]

No the scop values aren't visible which is a shame, you have to calculate using the heat loss values for your home. Yes servicing is needed but more to check the gas hasn't leaked and to look after those mini pumps and pipes keeping them clean. Not had a quote yet for annual service, sounds like a small job

[@USA-GreedyMenOfNoIntegrity]

You need a bib kit to catch all of the cleaning solution/dirty water runoff when cleaning indoor heads. It’s not a small job to clean the blower wheel after 3-5 years. I recommend installing a 1/4”/6mm foam pre-filter, sprayed with filter spray. The cheap plastic screen filters are junk.

[@peterclarke5323]

I was chatting to some AC installers on a commercial project and asking them what I need to do to service my heat pump. The response was keep the heat exchanger on the outdoor unit clean by using a garden hose or one of those tiny handheld pressure washers with a 90 degree head to get behind the unit. The other was to check the gas pressure every few years. On those indoor units there will only be air filters that need changing.

[@SuperDiagnostic]

@@EVPuzzle I was quoted £65 + VAT per-internal unit for the annual service which is needed for the 7 year warranty 👍🏻

[@nickieredshaw7835]

@@EVPuzzlebe interested to hear serviced cost when you find out as heard it still about same as boiler service 80-100£

[@brackcycle9056]

The condensation ? could you run it into a pot plant ?

[@EVPuzzle]

I'm sure you could just depends how much it extracts a day, I'm not sure yet

[@stevesswiftkontikiontour649]

Can I ask who did your installation And would we get a grant or a payment like feed n tarif and solar generator payment

[@EVPuzzle]

Ignite heating and cooling, Gt. YARMOUTH No grants for A2A