Green Building Forum - Multi split air conditioning (or other) for my home - advice please Tue, 19 Dec 2023 04:19:43 +0000 http://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303426#Comment_303426 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303426#Comment_303426 Wed, 20 Sep 2023 10:04:07 +0100 GarethC
We live in a Victorian sandstone building split into three flats, of which we're the 'ground' floor flat, but have a property below us as the land slopes away from the road.

Conservation area. Micro bore pipes, high ceilings and cornicing so little scope for insulation. Secondary glazed throughout with my own product. Four bedrooms. No chance

I'm minded to install 6 unit multi split air conditioning system to the living room, kitchen, three bedrooms and the hall, and retain our combi gas boiler for hot water and to top up the rest of the areas. I hope to reduce gas usage by at least 75% this way. Outdoor unit would be in our back garden which starts at the side of the property.

This is the point where my head starts to hurt. I realise this topic has probably be done to death and I should really just research further, but any observations about whether this is a decent plan, of there's a better one, gratefully received. Desperate to upgrade the heating system vaguely affordably.]]>
Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303427#Comment_303427 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303427#Comment_303427 Wed, 20 Sep 2023 10:40:14 +0100 Nick Parsons Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303432#Comment_303432 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303432#Comment_303432 Wed, 20 Sep 2023 13:09:10 +0100 GarethC
I take your point. I've just this morning been talking to an air con installer actually. My company has moved into a new industrial unit (from the small rickety one I asked this forum about a year or so ago) and I'd like a low carbon heating system.

I'll sound him out about his appetite for a domestic install. I can't be bothered with the cost and disruption that I think an air to water system would entail, nor the bureacracy if I wanted to apply for a grant (although they are particulary generous in Scotland).]]>
Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303438#Comment_303438 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303438#Comment_303438 Wed, 20 Sep 2023 14:29:40 +0100 owlman I was lucky perhaps, inasmuch as I found a local independent F Gas qualified aircon and refrigeration service engineer.
I opted to do a lot of the tedious legwork that he didn't want. I researched and bought most of the kit, especially stuff that I knew many of the mainstream aircon suppliers didn't supply, but which I wanted as part of the install.
I also did much of the prep, e.g. the outdoor unit base support and loft access points for the pipework, and power cable runs. All this cut down his time on site, and |I was quite happy for him to do the odd half day, leaving him free to do his usual service jobs.]]>
Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303526#Comment_303526 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303526#Comment_303526 Mon, 25 Sep 2023 18:06:17 +0100 jms452
We have a 2 unit split A2A - it's good.
Once you have six internal units though it's a big (Expensive system) and the heat really drifts upwards which will be a bigger deal with your ceilings. You'll also need to install something else for the hot water and maintain both the A2a and gas heating.


In your circumstances with a 7.5k grant available I'd consider biting the bullet and going the whole hog with a decent A2W install, bigger pipes and bigger radiators. If your boiler allows running some experiments in winter with your existing system seeing how much you can lower the radiator temp and still keep the house warm may be informative.

At least get quotes for both. charges:bigsmile:]]>
Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303527#Comment_303527 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303527#Comment_303527 Mon, 25 Sep 2023 21:14:20 +0100 tony
I liked Owlmans approach]]>
Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303528#Comment_303528 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303528#Comment_303528 Mon, 25 Sep 2023 21:45:42 +0100 GarethC
I'm just desperate to reduce our heating emissions. We'd even be fine if running costs rose slightly.

We already set our thermostat to 16 degrees, and would continue to do so even with the heat pump, which would hopefully help it cope with high heat demand.

Unfortunately I'm not sure we'd qualify for grant support. I think they'd advise that our property is unsuitable, but I think I'll give Home Energy Scotland a call anyway.]]>
Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303530#Comment_303530 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303530#Comment_303530 Tue, 26 Sep 2023 09:53:40 +0100 Artiglio
Someone keen to improve their property
Willing to pay higher running costs
Accept there is a cost for improvements
Willing to live at temperatures that not only very few would , but would be insufficient targets for rented property.
Has a property that isn’t that easy to adapt
Finds that there are not the companies out there to do the works required / would rather pick the easy jobs.

Surely there must be the realisation that there’s a huge gulf between the goals the nation has set itself and our abilities and financial wherewithal to achieve them.]]>
Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303533#Comment_303533 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303533#Comment_303533 Tue, 26 Sep 2023 17:55:39 +0100 Doubting_Thomas
https://www.heatgeek.com/

I've not used them personally, but have found their articles & videos useful in the past and I notice there's one on microbore pipework.

Their installer map covers some areas of Scotland too. Might be worth finding out if you can get a quote from someone local?]]>
Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303731#Comment_303731 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303731#Comment_303731 Wed, 04 Oct 2023 23:50:06 +0100 mike7
This has been working well enough here with just one emitter, plus the existing lpg ch. retained for cold spells, for 12 years now, except that one end bedroom is used a lot by my wife as a workroom and that does need a higher temperature, so a second emitter there would have been a good idea. The whole thing does rather depend on leaving doors open which happens to suit us fine, and it suits our situation in that we are both here most of the time so the heating is gentle but constant.

Quoting Artiglio above "Surely there must be the realisation that there’s a huge gulf between the goals the nation has set itself and our abilities and financial wherewithal to achieve them." I couldn't agree more. Small air to air heatpumps are a cheap and quick and hassle free way to displace a good chunk of fossil fuel and it grieves me that there is so little awareness of this option, and so much blind adherence to the custom of having a single heating system that does it all. They could be rolled out much quicker than full air to water systems, with little or no need for subsidy, less fear of committing to an entirely new system inexpertly specified and fitted, and far less disruption. They can start displacing fossil fuel now rather than having to follow the standard mantra of insulating and adding radiators first. The insulation can happen later, bigger radiators may never be needed. Then there are those who oppose it because it might be used frivolously for cooling, thus adding to emissions. True, but the net gain is still favourable by a large margin. It is possible to restrict the cooling operation to higher temperatures. I read recently there is a country doing this - India, was it? 28C IIRC. We may also be heading for times when even UK temperatures will threaten survival, when a cooled room would no longer be a luxury.

Edit: India has a default factory setting of 24C, Japan has default of 28C, so they can both be set to cool lower if reset. With its growing properity and stuggling grid India has a particular interest in encouraging careful use.]]>
Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303759#Comment_303759 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303759#Comment_303759 Thu, 05 Oct 2023 17:21:13 +0100 GarethC
@mike7, I've often considered it. I know that a single log burner can actually heat quite a lot of the house, so can understand that a single, centrally located air-to-air unit could work similarly.

Don't start me about the lack of support for A2A. It's particularly silly that the powers that be actively discourage A2A in Scotland, having adopted the approach taken down south. The amount of time they would be used for cooling would be minimal. I'm actually in consultation with Scottish Enterprise about this issue. If they -really- worry about cooling, we can ask Mitsubishi Electric nearby to sell air con with the cooling switches removed from the controls.

I'd argue they should leave the cooling function in there. At least it gives adopters an extra feature over the heating system their replacing, even if they'd very seldom use it. Currently it feels like you have to spend a lot of money, and sustain much disruption, for a system which won't work any better, or be any cheaper, than what you already have.

If they did only allow 'heat only' air conditioning, though, I suppose you could do away with the condensate drain, which would make installation even cheaper and easier, wouldn't it?]]>
Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303765#Comment_303765 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303765#Comment_303765 Fri, 06 Oct 2023 11:53:17 +0100 owlman I agree totally with your comments and they echo my own experience with A2A. As you say, we seem wedded to the single do it all system, CH and DHW, however inefficient each of those functions may be, in terms of finance, material cost, installation upheaval; when the alternative is staring them in the face.
The A2A technology is widely used throughout the rest of the world and from my experience is trouble free. No, we Brits prefer the over complicated A2W system of pumping hot water around the home. Sure that works, in a home designed, or refurbished, for it, but then if doing that you'd design a complex heating system out of the equation altogether,-- but as a retrofit replacement...Bah!

Heaven forbid that the hoi-polloi might cool their homes in Summer when the grid may be awash with green energy, or even if the home has PV to supplement their "extravagant" occasional use.
As for cooling generally; my own experience is that I've rarely had need to use it and only in one room. It's so damned efficient if it's set on manual I find myself switching it off after a very short while sometimes as little as 15-20 minutes but it is nice to find a cool refuge after working outside on a hot day.

@Gareth C
As mike7 says a 6 split may not be necessary, and even if it is then go for two x 2or3 splits, possibly in a stacked arrangement. That give a bit of flexibility, heating and cooling, and servicing.]]>
Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303790#Comment_303790 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303790#Comment_303790 Sat, 07 Oct 2023 18:41:39 +0100 Victorianeco
Would MVHR be a good system to distribute heat effectively? I think this is where a wet system comes in better with TRV's etc?]]>
Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303795#Comment_303795 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303795#Comment_303795 Sat, 07 Oct 2023 20:38:30 +0100 djh Posted By: VictorianecoHow would one duct air to air in a larger house?Using a forced air system. i.e. largish ducts with very noticeable fans. Forced air systems normally run with air much hotter than an air-air HP can sensibly produce, so even larger ducts would be required, or even noisier fans.

Would MVHR be a good system to distribute heat effectively? I think this is where a wet system comes in better with TRV's etc?
Not in most houses. The heat loss limit for a passivhaus (10 W/m² or 15 kWh/m²a) is chosen to be small enough that an MVHR can carry the heat energy required to keep the house warm. Any larger heat loss and an MVHR can't transport enough heat energy/power.

That's why multi-split systems exist; to distribute heat (or cool) over a wider area.]]>
Multi split air conditioning (or other) for my home - advice please http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303798#Comment_303798 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17963&Focus=303798#Comment_303798 Sat, 07 Oct 2023 20:59:35 +0100 Victorianeco
I'm thinking of my new house project, detached 4 bedroom on the seafront. I'll set up a new thread for that at will have different constraints for sure]]>