Air to Air Heat Pump: better than an Air to Water Heat Pump? We install for a YouTuber to find out!

This week we are installing a pair of Daikin MXM series air to air heat pumps for a KZbinr to review. He did consider an air to water system but wanted to go for the air to air due to the flexibility of siting, higher efficiency and ability to use cooling in the summer months. Beware - there may be mild hints and attempts at comedy, or perhaps soft core levity. Whatever. We hope you enjoy it and please do be sure to subscribe. It really helps the channel.
Be sure to check out ‪@mike-M0MSN‬ channel and his content.
Any commercial enquiries, queries or questions can be sent directly to me at [e-mail].

[@crit71]

Not a bad install for a bunch of plumbers 😜. On a serious note though.... I've been installing and repairing AC for over 30 years. I would never recommend fitting outdoor units on wall brackets on a residential property. Yes, the units are quiet but I can guarantee you will hear the buzz from the compressor if the system is running whilst sleeping.

[@tlaroche38]

Can absolutely confirm this, avoid brackets wherever possible! Especially because the compressors are variable speed so eventually they WILL find the resonant frequency of the wall they're on and be annoying In my old house the unit would sometimes vibrate the glasses and mugs in the kitchen cupboards, you couldn't hear the compressor but the jingling glass was annoying! My current house has them mounted on the floor and it's so much better haha!

[@RobFisherUK]

Interesting. Mine are sat on the ground on big rubber blocks. Was wondering about the pros and cons and hadn't thought of this!

[@delspark]

Nice and tidy work 👍

[@MCow123]

Fully agreed, wish I’d known this before installing our Daikin :(

[@robertblood3722]

Very well explained Dameon in a simple understanding way. We have had a A2A system for three winters and two summers very cost effective. Also had Solar for nine years and a battery for three years. Bob Blood Kent England.

[@David-bl1bt]

a very interesting & informative video, thanks for taking time out to share

[@stephenfoxall9655]

Good to see breakdown of costs, info on any grants, and eventually comparisons of running costs old against new.

[@heatpump8566]

That’s a lovely install for plumbers, very well done.

[@bingopriest]

Excellent video, good job

[@petervince4710]

Thank you for this video documenting the install of an air-to-air solution. Would you be able to post the specifications (KWH) of the 2 outdoor units and 7 indoor units. Most appreciated.

[@themartin1c]

Great video and explanation of the system and install. I'd love to install a Daikin system but currently got an LG split which is noisy as hell. Hope it breaks soon so I can replace with Daikin

[@davidw717]

😅

[@gavindyke2363]

Lovely job gents 👍

[@dameonhill]

Thank you! Cheers!

[@chrisjones6542]

19:38 which one, I’ve installed two single splits so far (lounge and kitchen) and kept the oil for this winter, thinking of a multi for upstairs before next winter… what flare tool did you use, also what did you put on the flare joint, I’m guessing to help the seal?

[@dontuno]

Fascinating stuff and further convinces me to go air to air. My mini split system has a SCOP of 4.1 and it produces a much more pleasant heat, albeit it was bought for its cooling capability. So in theory with my respective cost/kw for gas and electricity it should be approximately 20% cheaper to run than gas. Unfortunately I do not have a COP value so perhaps my figures are slewed but unlike gas heating the wait time is pretty much instant and I actually achieve setpoint which is something the gas system struggles to do.

[@grahamlochrie9918]

Just watched the video very well done can u let me know what the efficiency is for the daikin units heating your house we are in the process of ordering an air to air multi split system

[@nicdensley4104]

I'm looking at an A2A system, can I ask if you experience any vibration through the wall brackets into the wall?

[@barriedear5990]

Excellent explanation of efficiency of a2a v a2w. Can I ask about how much more efficient a modern R32 A2A heat pump might be compared to R410A inverter A2A heat pump circa 16 year old.

[@barriedear5990]

@@zlmdragon. Thanks. Just to confirm, you mean the R32 gets SCOP of 4-5?

[@caterthun4853]

What do you use to heat domestic hot water... And the towel rail in bathroom

[@iansmith788]

What we do now is heat the house in the winter months to 19c with gas central heating, we then use an air con heat pump to heat the room we spend most time in to between 21-23c, we have solar energy providing a lot of the electricity required which varies but is between 500 and 1000w usually and provides about 2500 heat energy so very efficient, I estimate we save about 10-20% on our gas usage in winter when we heated the whole house to 21c using gas central heating only.

[@davidw717]

Interested to know a price range for this set up? Been thinking about A2A heat pump for upstairs.

[@sjcsystems]

This is exactly what I want in my bungalow. The disappointing thing is that you haven’t covered the hot water system. I also note Dameon there are no contact details on your channel, surely that’s a missed marketing opportunity?

[@dameonhill]

Simon you are right. The hot water follow up video will be uploaded at the weekend, as will a follow up video on the performance of my heat pump hot water cylinder. Any queries can be sent to me directly at [e-mail]. Thanks for your feedback

[@jorkirasalas2726]

Could you clarify the monitoring capabilities? Electricity usage to drive the compressor is simple, e.g. with a Current Transformer, but have you monitored the refrigerant flow rate and flow/return temperatures to calculate the COP in realtime? Id be interested in that for the -5C to -10C that we saw in December, and with the low external temperatures+high humidity that we’re currently seeing.

[@jorkirasalas2726]

@@zImdragon I suspect it *can* be done; its relatively simple for an air2water heat pump, heatgeeks are doing it in realtime: m.kzbin.info/www/bejne/jmfUeoNuqNODjZo The electrical load used by the external and internal units of an air2air heat pump is all supplied from the exterior unit so a simple CT clamp on the external unit’s live cable will measure that. I’ve seen reference to measurement of the heat delivered part of the equation using wet and dry bulb thermometers and air movement sensors, however I suspect it should be possible to measure it in the same way as heatgeeks did above, by measuring the difference in flow and return temperatures of the refrigerant together with its mass flow rate. Temperature should be easy but not mass flow rate I’ll agree. Heatgeeks used an inline water flow meter but for an a2ahp it would need to operate with the refrigerant so a simple device cant be used, but I think an external ultrasonic flow meter might work (I’m assuming this monitoring isn’t done as the standard a2ahp equipment fit).

[@ChrisJakins]

This is of great interest to me as we have a very similar system here which was installed in October. We have for now kept our boiler for hot water but plan to change that in the future. This coming cold December will be the first serious test.

[@GcS1515]

How did December go? All ok I expect. I'm also looking at a Haori or Mitsubishi A2A system and hoping to be gas boiler free later in the year.

[@ChrisJakins]

@@GcS1515 all good thanks. We haven’t been tempted to run the boiler all winter. These below average temperature months do use a fair bit of electric but it isn’t worse than expected. Our most costly month was January at 620kWh. Dec was 610kWh, Feb was 330kWh. Last year’s gas was 1800kWh per month November to March and it was warmer weather than this winter. Our house is occupied most of the time too. We shut down at night to save money same as we did with the gas unless it gets well below zero when I leave it ticking over at 16 degrees. Normally run it at 18 to 20 degrees. Hope that info helps. Good luck.

[@GcS1515]

@@ChrisJakins thanks for the reply. figures look good.

[@sailingoctopus1]

Very good video. I'd be interested to know how noisy the indoor units are. Is the noise a problem in bedrooms at night. I worry that the indoor and outdoor units seem ugly. I suppose one of the benefits is that removing radiators will be freeing up useful wall space, whereas the indoor AC units don't consume valuable wall space. Radiators don't seem ugly, but the indoor units do.

[@Dr.Stacker]

They look hideous, like being in a cheap benidorm hotel room

[@johnfreshwater3790]

Where did you get that pop up tent from? Great video!

[@denishurley1358]

Just wondering if the indoor units require an isolation switch also as well as the outdoor units? I'm hearing conflicting information

[@wobby1516]

My only negative comment about this type of system is all the ducting around the house. It for me at least, looks a bit commercial and that’s possibly the reason that would put me off the Installation. On another note it seems a real pity that the £5000 government grant isn’t available for this type of install. Is the heat pump supposed to be out of plumb left to right?

[@RobFisherUK]

Interesting video! I'm running a similar experiments, though I have kept my gas system. It means I could try all gas one day and all AC the next day. AC is definitely a lot cheaper most days. And a bit cheaper on the colder days. But AC misses some spots, like the bathroom, so on a cold morning I like to run the gas for a couple of hours. For working from home, AC is a hands down win, because I can heat just the room I'm working in. But today, which was very cold, I started to get annoyed by the defrost cycles because it would blow cooler air at me. It is very good though, and really heats things up fast. How do you get on keeping your bathrooms warm and dry with no heat in them? Perhaps you have good ventilation in the house.

[@garywright8846]

I think you need to get your installer back as depending on the make you can stop the indoor unit running on defrost, it’s normally a toggle on the outdoor unit PCB. Having it running is hopeless.

[@garywright8846]

Great job, very impressed with the triple vacc, not many installers do that. I think these systems make allot of sense in the UK, just be aware these systems are heating the air unlike a gas boiler that basically gives you radiant heat. He may find as soon as they turn off the temperature drops rapidly. Also defrost is an issue but hopefully on commissioning you set the fan coils off on defrost.

[@RobFisherUK]

@@garywright8846 it does shut off during defrost, it just seems a bit too keen to start the fan after the defrost cycle.

[@delrey-p]

Which no loss valves have you got?

[@singlendhot8628]

If it isn't too broad of a question, what did an installation like the one done here cost the owner?

[@kaushikkathiriya4389]

Hi Dameon, what are those strings you put inside the pipe when you bend the indoor pipes?

[@jsimnable]

my guess is a "solid core" to prevent the pipe from kinking when bent

[@SergeRubcov]

I wonder what is the current cost of this kind of system, including materials and labour? Brilliant video by the way!👍👍👍

[@dameonhill]

Thanks for your email Serge. I have replied to you.

[@grahamlochrie9918]

I'm also interested in a cost for a similar system for my house could you send an estimate please

[@secrecy4real]

I’m also in process of planning a refurbishment and this has made me question my plans for an air to water system. I do wonder how much this costs compared to a similar air to water system plus installation of the underfloor pipe work, etc.

[@nick.bender]

What’s the SCOP rating of this system?

[@RichardABW]

Thanks for the interesting video, however I don't know if I could handle this much plastic stuck to the outside of my house. 😖

[@sailingoctopus1]

Interested to know how the external units are affected by corrosion. Our house is exposed to very corrosive wind blown salt spray from the sea, hence my concern.

[@malachy1847]

Good Point, you can get many Units that are constructed Specially coated to give long term protection deal with Coastal Salt corrosion

[@icereturns7867]

I'm considering a heat pump, I like the idea of air conditioning too, however I probably wouldn't be ready to swap all the radiators out at the same time the heat pump is fitted. Would it be possible to fit a heat pump that was capable of cooling, but only use it for radiators and hot water for now ?

[@RobFisherUK]

You could do what I did and keep the gas system and just add the air to air stuff for AC cooling and heating. I end up using gas and AC heat in different situations, and I'm not sure I'd want to give up the cheap, powerful hot showers from my gas combi boiler.

[@zjzozn]

Look a little busy on that outside side wall. Are the inside units noisy and heat a bit breezy / drafty

[@ivanovpi]

that's why you have A2W option with underfloor heating. I also hate aircon, so A2A for heating is not what I'm going for

[@markwilliams5654]

When it's below 7c outside you won't get anywhere near a cop of 5 more like 2.5 which makes it cost more than gas

[@aidandillon9520]

Great video, really enjoyed it! Have you installed a multi-split VRF/VRV, with heat recovery, providing both air-to-air air con AND an air-to-water unit (for DHW and underfloor heating) all with one outdoor unit? Watched a video on Heat Geek where this was discussed as a viable solution, but I can't find any actual product that would do this.

[@dameonhill]

Hey Aidan. The short answer is no, but I agree it would be a neat solution.VRV hasn't really made any headway into the domestic world yet but it is only a matter of time. The applications would be fairly small though I think. There isn't much free heat worth moving around from elsewhere in a domestic property such as there would be in a commercial environment - say moving heat from a server room into offices etc. I'm not sure the case for the additional cost would stack up. Daikin have told me that there is a new 4 port outdoor unit with a refrigerant split 150 litre hot water cylinder coming out early in January. I have made a strong case to get my hands on one first so we can install one and try it. I have to say that standalone heat pump cylinders are excellent. The Daikin Altherma M HW that I did a video on in particular is great, if only they would capitulate and sell it in the UK. I am pushing - and I do think this will happen as more people lean towards air to air and look for hot water solutions.

[@burakokumus6040]

Samsung RD160PHXEA, it's a 16kw model. it's not a new model but the equipment can do what you want Aidan, except heat recovery function. You can have x number of air handler indoor units + 1 hydro unit (and a boiler for DHW if you want) with it. For that specific model (RD160PHXEA) the total capacity of the indoor equipment shall "not" exceed 16KW. I use it in my home. it has smaller capacity models aswell 8-12-14-16. it works both ways, as air to air and air to water at the same time.

[@edithmaggie]

I totally agree with you!

[@richardc1983]

LG Multi V with heat recovery hydro box for hot water/underfloor heating is what you want.

[@aorange999]

​@@richardc1983 looked into this one a few years ago and they were only going to approve the hydrobox for underfloor and not panel radiators.

[@edithmaggie]

super contente!

[@The_GG_OG]

Researching exactly this option, appreciate mike got mates rates but what is a ball park total install cost for this 7 unit system, what would I expect to pay for a similar install (ie all the headers on an outside wall? £10k 15, 20?

[@Dr.Stacker]

Think about the numbers you are throwing around are you really prepared to pay anything over 2-3K for a heating system

[@johnhunter4181]

I got two 3.5kW Panasonic minisplits installed for £3.5k all in this summer. Having two singles gives slightly better performance. You can run just one in spring and autumn and a you get bit of redundancy too. 👍

[@jerrywatson1958]

The dinosaur was funny!

[@manikdesign]

I think I’ll just stick to all in one unit this looks complicated even for the plumber.

[@nielsdaemen]

Any updates on this system?

[@peteg8920]

So the indoor units are all installed high up on the wall. Radiators low down , heat pumps high up.

[@eddiereed5025]

when he says we aren't using as much gas surely the gas would have been disconnected to the house why pay the standing charges presumably for cooking only when could be converted to electric , would like to know if gas disconnection costs anything .

[@caterthun4853]

If gas cooking is your thing. Stop paying standing charge and install bottle gas.. A 25k bottle will last a long time

[@ragincrinz1457]

I'm looking to get air to air in my house. Who can I contact?

[@JohnnyMotel99]

Our Gov wants everyone on HeatPumps, but flats are a difficult area to convert. A to A would be an ideal solution.

[@MerrionGT6]

We had a Samsung multi-split a year and a half ago and a SunAmp heat battery for the hot water - replacing gas combi (DHW) and radiators. It is just sooo efficient. Adding solar would be the next goal. Also good to see mounting the outdoor unit good and high up so there is much less risk of cold air re-entering the unit and reducing efficiency. (Related I wish there was some way to have a 40mm condensate pipe so there would be absolutely no chance of it freezing up .. there was some ice in it in the recent very cold snap and another 2 weeks of that might have been a problem)

[@USA-GreedyMenOfNoIntegrity]

10:24 😅😂😮

[@nixonsmateruby1]

Really "hamming" it up.

[@richardc1983]

Disagree with the comment that air to air indoor units only need to have refrigerant going round at 29c. The refeirrgant is more like 50c, and my r32 unit now is going more like 80c refrigerant giving a 50c air off... At lowest output the unit this still blows about 38c. The units won't blow of the coil isn't above 35c to avoid cool drafts. Agree with much the rest.

[@dameonhill]

Interesting observation you have there. All of our Daikin R32 systems max out at around 23 bar (39 degrees C). When idling they sit at around 18 bar (29 degrees C). I don’t recall ever seeing an R32 system above 25 bar.

[@richardc1983]

@@dameonhill to get an air off of 39c and say 20c air on the refrigerant circulating will be at around 70c, r32 is even more efficient than r410a in heating and there are higher compressor discharge temps. Have a look in the Daikin service checker at the pipe in/temps. It may be less extreme on the splits but the multi units really do belt out the heat. Seen a few r32 compressor failures too due to how harsh they are in heating. Operating pressures do not relate to discharge temps, so many variables such as outdoor temp, indoor load, humidity.

[@richardc1983]

@@zlmdragon. I don't know what your problem is, I don't know you, your clearly jealous because I am better than you :)

[@markwilliams5654]

Good luck with running a heat pump with solar panels in the winter lol

[@markwilliams5654]

You don't need ac in the UK if your house has good insulation

[@chetmyers7041]

Carbon Dioxide is a necessary plant food.

[@markwilliams5654]

It will cost more to run than gas and your cop won't be anywhere near 5

[@lookoutleo]

42p kWh electricity in Scotland and standing charge 49p . No mains gas :( come fit and air to air heatpump :)

[@lookoutleo]

@@zImdragon in the land where Westminster sells all the infrastructure to highest bidder and they can charge us what we like. Where I live we have huge hydroelectric dam but still that's what I pay

[@lookoutleo]

@@zImdragon where do you live that would cause that?

[@markwilliams5654]

Say you need 70kwh of heat for house and you only get a cop of 2.5 it's not at all eco and cost thousands get ready for your electric bill

[@alanviolet4102]

I had no idea the installation was so ugly, I though all the big connections would be in the wall cavity.

[@knowbs2122]

That wall hung unit looks out of level

[@nixonsmateruby1]

They're still outside almost 15 minutes later. You're welcome.

[@Umski]

Wonder what Heat Geeks’ view on this is 😬

[@markwilliams5654]

Why would you spend thousands to have cold bathrooms for im confused

[@markwilliams5654]

Who cares about the scop value I dont use my heating in the summer lol it's about the cop efficiency when the outside temp is cold and it drops off massively

[@lawsonspedding6136]

Edge of apocalypse ? FFS keep it real !

[@markwilliams5654]

Freeze and costs loads to run lol

[@MaxStArlyn]

4:00 …Yes you are right it is cringe.

[@davidscott3292]

Too much chat, particularly the first ten minutes.

[@zigzacpaddywhack4212]

Not enough chat in the last 22 minutes in my opinion

[@garyshoulders1676]

wouldnt the client already have a radiator system in their house? surely you should have just kept that hydronic system, ripped out the boiler and heated the water with the refrigerant ? I live in new zealand, and we have lots of heatpumps systems here and i cant stand them. they dry out your eyes and look ugly.

[@ecoterrorist1402]

you lost me when you said I'm going to heat my home with the solar panels, your 2kw or 3kw array will produce about 20-30 kwh in December, you ain't going to heat your home using your home energy. Est avg temps in winter is 5 & at night near zero. air to air will have a COP of maxuim 2-2.5 scop is a con as at high summer temps hating i no problem. should of kept the Gas & added some units.

[@UrbanPlumbers]

My air-to-water installs run at cop of 2.7 - 3.3 this cold December. Surely air-to-air can do over 3 as well?

[@ecoterrorist1402]

@@UrbanPlumbers at flow temps of 30 maybe, but air to air systems run at 60.

[@waqasahmed939]

@@UrbanPlumbers 3.3 isn't enough imo to be viable atm I'll get a heat pump eventually but there's a lot of other work I wanna do before, including sit tightness, upgrading windows, radiators and maybe pipes too

[@UrbanPlumbers]

@@waqasahmed939 I get 3.3 in Dec with annual scoop of 4.5

[@waqasahmed939]

My 3.2Kw system produced 70 kWh this December, on a West facing roof I intend to double that up too.

[@markwilliams5654]

Your lying about the cop value when it's cold the cop value is massively effected and you won't get any where near 3-4 cop

[@CT-vm4gf]

Depends how cold. And how often, so what if the cop isn’t as good on the days it’s super cold.

[@rupertwilson7020]

Panasonic recent Air2Air models may get COP 1.9 at -25C .. the numbers are a little better than Air2Water.

[@markwilliams5654]

It's a waste of money and not eco the cop is massively wrong from reality it's cheaper to use gas and your house will be much hotter

[@zyrtec455]

Air2Air heat pump could be used as AC as well during the summer month tho

[@johnhunter4181]

It depends, our heating bills are half what they were with gas. Install was £3.5k all in.