Air to Air with hot water systems

JayBee66

https://www.boards.ie/discussion/comment/121556642#Comment_121556642

I'd like a Toshiba Haori system myself. I start ringing around aircon installers in south Leinster tomorrow.

I'll be working off a combination of the lists available on these two URLs...

https://hes.seai.ie/GrantProcess/ContractorSearch.aspx

https://www.fgasregistration.ie/certifiedcompanies

I hope they don't all foist their favoured manufacturer on me.

poker--addict

Some of the f-gas people may not routinely do it - but might be able and willing to sling in the systems if bought by house owner. Might be better value than lads doing the supply and install?

The devils

I'll pm the guy I used

My install was 2 x 5kw daikin

audi02

Hi All,

We're currently building a granny flat at our house. 2 small double rooms, a single box room, bathroom and kitchen living area. Total size is 14m x 7m. Looking at all our options for heating but my main thing is constant hot water and I would like to be able to control heating from my phone. Is a2a the way forward or would we be better sticking with a combi boiler?

Originally I was thinking electric rads in all rooms and installing alot of PV panels and a battery to cover the majority of the cost so the only bill is electricity.

Any advice greatly appreciated.

Thanks in advance

headtheball14

https://www.boards.ie/discussion/comment/121545912#Comment_121545912

I think it is a fair bit of ignorance tbh . I had someone out from one of the retrofit companies. he said he had never heard of air to air, it couldn't work if I hadn't insulated the house and it had to have cost a lot more than I told him I'd paid (about 1800)

also those promoting policy options are generally opposed to the air con element so don't want to promote it.

RetroEncabulator

TBH, the demand for Air Conditioning in Ireland in hot weather's going to be fairly negligible anyway.

unkel

https://www.boards.ie/discussion/comment/121564271#Comment_121564271

That's what people said in the Netherlands up to about a decade ago about air conditioning systems in homes. Now many people are installing these systems over there.

RetroEncabulator

The Netherlands has a potentially far more continental climate though. Almost every model for Ireland shows climate change just making it wilder, windier and potentially a lot wetter. Heat here is pretty unlikely. Southern England is probably the only part of these islands that's likely to get issues with high temps.

The biggest risks are being washed out of it with floods and storms.

unkel

https://www.boards.ie/discussion/comment/121564315#Comment_121564315

Being able to cool, for me, is just a free bonus of an A2A system. What attracts me the most is that it will replace my gas boiler for heating the house and will cost less to install than a new gas boiler (maybe €2k in total) and will be cheaper to run because of the COP of maybe around 2.5 on average

I have no appetite for getting a €15k A2W system installed and my house (built '99-'00) isn't well insulated so I would never get the very high COP values that some people get with underfloor heating in well insulated new homes

JayBee66

https://www.boards.ie/discussion/comment/121564353#Comment_121564353

Remind me what the layout of your house is.

I'd love it if a single A2A unit would heat the whole of my bungalow (one floor, three bedrooms, office, lounge, kitchen, bathroom, en suite, utility room, hallway) but I'm sure it wouldn't.

That's my conundrum. How many units do I put in? An installer is going to want to maximise profit and fill the house with the things. I want to minimise cost and put in just enough.

micks_address

https://www.boards.ie/discussion/comment/121564353#Comment_121564353

Definitely agree with the bonus of air conditioning. Some days/nights in the summer it's just uncomfortable. Mileage varies of course.

The devils

Had my ac on for most of the summer, it was fantastic. As said before on previous thread upstairs 2 large bedrooms and 2 bathrooms (not bother about bathrooms but still does the job)

Downstairs kitchen , dining area and 35 m2 extension

If i really want my hall cool or heated ill have my upstairs louver set up and down.

Yes ireland is not the warmest by far - but if it makes my family more comfortable and brings my gas down happy days

As Unkel says above - eventually I'll get rid of boiler and et another ac and duct 2 bedrooms downstairs and front sitting area.

poker--addict

As I get towards quotes for 5 or 6 units a regular A2W heat pump seems to be more or less same price (with underfloor heating already in place), so I share the conundrum, large house here, so there is no way two units alone would heat the house.

Two would take the "extreme" summer heat out before kids go to bed though.

If i did not have UFH and existing water though I would be say a2a is a no brainer based on initial research. Reasonable coefficient of performance , rapid targeted heating. Current theory is 2 a2a units in house would see cooling ability in summer, expensive old heat pump running less (not at all) in shoulder months, and taking peak of heavy usage away on coldest days

unkel

https://www.boards.ie/discussion/comment/121564464#Comment_121564464

standard 3 bed semi with relatively large north facing so cold living room, converted attic, large kitchen extension + converted conservatory (south facing and mostly much better insulated) and separate large well insulated garden room

I used to heat my house mostly with two large crypto mining rigs in conservatory and living room, and we don't heat bathrooms / bedrooms much, so plan is to compromise and have 2 mini split systems for those two rooms and then use additional heating if and when required in those other rooms, like far infra red panels. Will likely get portable air conditioner / heater for shed

My main problem is that I only have a 12kVA grid connection, would really need 16kVA if I wanted to keep using only 5c / kWh electricity that I get between 2AM and 5AM (have large battery and powerful inverter to keep me going 24/7 on that cheap rate)

With gas being double that price and a COP of two, the savings would be enormous. Cost of the grid connection upgrade is over €2k though, which I am struggling to justify

Muahahaha

https://www.boards.ie/discussion/comment/121559669#Comment_121559669

In Leinster give the company who installed my A2A system a ring or email for a quote. Youre unlikely to find them with a Google search as hes a commercial refridgerant engineer who does residential A2A installs on weekends. I only found him from the recommendation of another Boardsie here who also installed A2A and was happy with it. He supplied me Mitsubishi units, not sure if he is tied to them or if he can source Toshiba. His installation fee (bearing in mind this was 4 years ago) was 500 euro and the equipment cost was 1,300.

https://www.coolrefrigeration.ie/

poker--addict

to understand size of your job, how many units did you install muahahaha?

Muahahaha

https://www.boards.ie/discussion/comment/121566292#Comment_121566292

One outdoor unit and one indoor. which heats a 45sqm open plan living/kitchen The outdoor unit is specced to accept a second indoor unit if I ever decide to get another unit for upstairs to replace the current panel heaters in the bedrooms.

SomeGuyCalledMi

Some priceless info in this thread. Thanks to everyone who contributed.

I too am thinking of going down the air-to-air route due to the extreme costs of the wet systems. Our house was built in 1995 and currently uses natural gas.

Here is a link to the Toshiba retail prices. On page 67 they have a heat pump with four internal units for €1,600 which I assume excludes installation. For some reason, the price rises substantially when you go for the higher output systems

https://www.toshiba-aircon.co.uk/wp-content/uploads/2023/11/Toshiba-Mini-Retail-Price-List-ROI-effective-16-January-2023-bookmarks_v12.pdf

You can use the more stylish Haori downstairs if you like. Our open plan room is 50 square meters and hard to heat despite good insulation and triple glazing.

For hot water, I am looking into something like the Vaillant arostor which is a tank with its own built-in heat pump. This can go in our utility room so the noise won't be a problem. The Daikin multi + is another option that people here have mentioned.

I'm getting a home energy survey done first to figure out the insulation situation. More to follow.

RetroEncabulator

I'm wondering about this as a supplemental system in a fairly large late 1970s house, which has been somewhat upgraded - has decent insulation and triple glazing.

It's a two story house, but due to the layout there's plenty of attic space for ducting / piping / wiring etc - so wouldn't be hugely challenging compared to laying pipes into the floors.

We're looking at putting in a fairly maxed out solar panel setup ... so I'm looking for ways of using up the energy and reducing the bills.

I'm not sure I want to completely rip the place apart, lifting tiles and hardwood floors to get new plumbing in, nor do I think I necessarily want to get rid of the gas fired system just yet. I just want to move away from it as much as possible as it's ludicrously expensive to run. Even with the insulation upgrades, zoning, thermostats everywhere, solar hot water and a Viessman modulating, condensing boiler the gas bills are still painful.

The plumbing that's there is old, but it's fairly high spec, lagged properly with armaflex etc and the rads are all quite nice slimline ones. thermostatic valves on every rad, some of them are digital with wall stats in the rooms we use most and also 3 zones with stats.

Have been trying absolutely everything I can think of to get the prices down without making the house freezing.

JayBee66

https://www.boards.ie/discussion/comment/121576087#Comment_121576087

Other than a Dublin company named after a Hindu deity I can find no other Toshiba installers in Ireland.

Are we expected to buy it ourselves and chance any jobbing installer?

_Brian

Great thread... tempted to go for this style of system in upcoming renovation so am gathering as much information as I can...

I see these systems dehumidify as well... Does this feature run with heating mode ?? I'm considering this for an old property and this is an attractive feature

graememk

https://www.boards.ie/discussion/comment/121901592#Comment_121901592

Possibly only when cooling, as you need something "cold" to dehumidify (well in a A2A heatpump setting)

_Brian

If anyone has heating costs they are willing to share I’d love to see them.

The devils

https://www.boards.ie/discussion/comment/121902203#Comment_121902203

Haven't used that much in March due to solar upgrades etc..

_Brian

https://www.boards.ie/discussion/comment/121902939#Comment_121902939

Wow.

Hope you don’t mind me asking some questions

So Feb for example you used 70 kwh for heating, was that the sole heating source ??

what sort of area are you heating and would you have any idea what your ber rating might be.

were looking to set up an 80sq meter 1 bed appt for my daughter, trying to understand if this might work. It will be the ground floor of a stone house we’re renovating for her. The first floor will be empty for the moment, so she can complete the work or extend in the future.

The devils

https://www.boards.ie/discussion/comment/121903167#Comment_121903167

No not at all

So I also have gas heating and stove my house was c3 and now a2 or 3 can't remember of hand.

Dormer Bungalow

1 a2a in 80m2 area

2 upstairs roughly the same

Front area has 2 bedrooms and sitting room no a2a (stove here).

Daikin 2 x 5kw wifi systems (super efficient)

I have solar and storage (batteries) So in the future my FEB result will be higher (I'll be charging more electricity at night and heating house with it during the day)

The daikin units have a silent mode (brilliant like a whisper) heats area very well and very quickly imo.

I have downstairs heating everyday from 5 to 6 during cheap tariff and it's cosy when I come down from 6ish on..

Throw more questions on if you want and I'll get back 👍👍👍

Ps the daikin I have is a++ and there is another version that'd a+++

poker--addict

Nice to hear it works quickly.

I am not sure we can read much into asking people for KW usage where there are other sources of heat, it doesn't really tell anything?

Have had two quotes now, disappointed that they weren't far cheaper than an a2w setup.

graememk

The F gas certification intrigued me. - As more and more are R290 (propane) driven.

F gas is :Fluorinated greenhouse gases

Which are:

Greenhouse gases are those gases which contribute to the greenhouse effect. There are six greenhouse gases as follows:

• Carbon dioxide (CO2)
• Methane (CH4)
• Nitrous Oxide (N2O)
• Hydrofluorocarbons (HFCs)
• Perfluorocarbons (PFCs)
• Sulphur Hexafluoride (SF6)

This one, the working refrigerant is R290, Propane, which is not an F-Gas

https://www.buyitdirect.ie/p/12000-btu-panasonic-powered-easy-fit-inverter-wall-split-air-conditioner-with-5-meters-pipe-kit-and-5-years-warranty-eiq-12wminv

(it does say it in the description)

@unkel a Semi DIY could be a lot more promising now?

_Brian

https://www.boards.ie/discussion/comment/121903353#Comment_121903353

We would be putting on a multi fuel stove as backup.

_Brian

https://www.boards.ie/discussion/comment/121903353#Comment_121903353

a question on use.
when setting programs, could I say have a number of heating periods AND then at some stage a dehumidifier period of say an hour or two. Is that sort of how it works ?