Portable air con for surplus

I looked at this as well but most things I found required a horrible hose type thing to go out the window.

What type is that @Jonathan

Get one of those wall mounted ones. No issues with heat transfer through the hose or gaps around to make it inefficient.

Can be used a heater too.

https://www.wholesaleheaters.co.uk/powrmatic-vision-3-1dw-twin-duct-air-conditioner/

Yes, comes with the hose, but that's no good if you're letting the ambient air back inside. The window seal is like a plastic-y material which attaches to your window with velcrow and you stick the hose out through it. It's just to try to keep the warm air out. Obviously it's not a perfect system, but it's good enough for a small/non-permanent solution.

On the noise front - the one I have has 2 power settings. It's quite noisy in the higher power setting, but I didn't have a problem with the lower setting. It's similar to the amount of noise produced by a dehumidifier.

The permanent solutions essentially have half of the machine located outside, which gives them a huge advantage in terms of noise and dealing with waste heat. The all-in-ones are never going to be able to complete with that, but on a hot day they still produce lovely cold air.

Looking into the possibility of adding a split system (or two) that can do both AC and heating, something similar to these: https://www.buyitdirect.ie/p/multi-split-27000-btu-smartapp-wifi-inverter-wall-air-conditioner-with-3x-9000-btu-indoor-units-to-a-single-outdoor-unit-iqool-3ms9k9k9k

Just wondering if anyone here has done something similar and can suggest a decent installer in the Dublin area

Ok perhaps a misleading title.

Our house bakes in summer with solar gain particularly upstairs. Air con units would basically have no electricity costs now that solar in installed, so I am wondering has anyone installed air con?

it's rare in Ireland but summers do seem to be getting hotter, and a lot of new houses seem to be hard to cool too, and throw on the solar to power it for free and maybe this is a space which will grow?

Curious if DIY is an option for install?

The average annual temperature in Ireland is about 10°C. It's why all those data centres set up shop here - free cooling. The annual average temperature in Sydney is about 20°C.

No, I do not think this is an area that will grow.

Unfortunately my problem is upstairs so no chimney to shove pipe into.

i think it's 9000btu, so not the biggest but not small either. Like you say, running it during the day, off at night. But finding once off it's not long before temps up again, and I'm blaming the lack of air tightness with pipe out window setup... also surprising how little the air moves to the adjoining bedroom beside it.

For us it's stored heat in the external red brick walls that travels internally. Sun travels around the house from morning to evening with nothing blocking it. House is all red brick - which 'sponges' up the sun.

Pumps out as radiant heat all night. Like an UFH when you don't want it :)

Bedrooms stay well into 20s at night during really hot spells. Beside a main road so can't open windows or no one can sleep. Windows open until bed time and temp climbs as soon as closed.

Would putting the vent pipe up through the attic hatch be an option? It's generally outside the insulated space and is probably well enough ventilated to remove the warm air being added

Most houses these days have the high tech Irish ventilation system (big hole in wall with cheap plastic vent cover) so I guess you could use those if you have them?

That's probably what I'll end up doing, but it kind of fixes the air conditioner into one room which is a bit wasteful for the 1 week a year it's needed, and negates the portable bit

As someone who has had a single-hose portable unit for the past few years - I would say don't do it.

I'm not saying don't get any A/C, but just don't get a single hose units. Especially if you intend on using it in rooms you want to sleep in.

They are are loudest, and most inefficient A/C units you can get. Even at a lower-blow setting, you will still have the noise of the compressor circulating the refrigerant. It's much like a fridge, except louder.

Also, whilst the hot exhaust air goes through the hose and out the window; that air originates from inside. This is a problem for two reasons. Firstly, you are using electricity to cool the air in the room, only for some of the air (which you have used energy to cool) going straight back outside; and secondly, pumping air out of the room lowers the pressure within the room which then means that external air is sucked in.

As others have said, the only semi-good window seals are the ones which work on sash windows. If you have windows which hinge outwards, the seals are not very good at all (but better than nothing). I am looking into whether I can tie the unit into the room vent, but I need to try to get/make an adapter.

Better systems exist.

2 hose units suck in external air to dissipate the heat generated by the unit, which is much better as you aren't exhausting your cooled air, and you're not creating a pressure differential. These units seem to be fairly rare though.

You can also get split 'portable' units, which are like mini-versions of the installed A/C units. These keep all of the hot stuff (and some of the noisy components) outside, with just power and refrigerant lines connecting the two. These are expensive though.

Best is a permanent install - but this is more expensive again.

Somewhat OT, but I remember reading a review of an indoor heat pump water heater with an integrated tank.

I was very confused about the reviewer saying that had the exhaust going into the attic. I was wondering why you'd be dumping cold air into the attic in winter, then I realised it was in California where winter is a bedtime story to scare children 😂

The problem is these new A3 rated houses are pretty excellent at retaining heat. Great in winter when it's freezing out, not so ideal in summer

I'm also pretty sure the insulation has a radiant heat barrier (tin foil) on the inside, but not the outside. So it stops radiant heat escaping, but allows solar gains from the sun. Again, great for winter, not great in a heatwave since it effectively warms the house up

I agree that airflow helps a lot, had a few fans last summer which kept things tolerable in the heatwave

The main issue there is you need to keep the fans going through the night otherwise the heat builds up again. Also if the outside temp is 27C then you can't really magic it much cooler with a fan. Might knock a few celcius off but it'll still be extremely warm at night

I guess the idea with an air conditioner is to "store" cool air in the house during the day and stop the house becoming overheated while the sun is out

I don't think it'll work miracles however because you'd have to cool the entire house, otherwise you'll have warm air coming in from other rooms

I installed a mini-split in the garden office, I got it for the efficient heating (SEER 6.2), but it's free cooling in the summer (the office can get quite warm).

I made a few phone calls to get quotes in Ireland, but most were commercial installers or wanted stupid amounts of money to do it, after a bit of research I opted to do it myself.

You can get a kit that comes with everything you need, including (this is the important part) pre vacuumed lines - if you don't get these you'll need to have someone out to pull a vacuum, or get a pump to do it yourself (the units all come with refrigerant preloaded). All in the kit was about 1000 shipped on a pallet. Mitsubishi 2,5kw. It needed a hole though the wall for the lines, drain and power connector - about 5cm - that was the hardest part.

It's really quiet and can run at a very low power, highly recommended.

I'm an average DIYer, was nervous going into it, but the reality is that that when you go outside Ireland to warmer climates you see mini-splits everywhere as DIY installs, so they are designed to be easy install. In the US there is a brand called Mr Cool, that uses similar connections, lots of youtube videos on how to do them that got me looking at this as an option. Hardest part was putting a hole in the wall, the drain must be facing down so you have to keep that in mind

This was the kit I got on ebay, you can specify mounts and the length of connections between the units, came with instructions. Unit works well, but the Mitsubishi App isn't going to win awards for innovation.

There isn't a pressure gauge, but there are a bunch of connectors that I'm sure you could attach to if needs be. I'll be treating it like my car AC, if the performance drops then I'll see what the issue is.

When running it tends to run low and slow, only taking a 200Ws or so, I've only had it a few months so your mileage may vary.

You can have the refrigerant pipes run any direction, but the drain pipe cannot run up - the ice buildup on the inside unit melts and the water has to drain (it's not pumped), if the pipe runs uphill the unit will leak. The drain pipe doesn't have to go back to the outside unit, it just needs a drain somewhere.

Think SD_dracula posted one before that could take up to 3 indoor units / splits. Can't recall if that was DIY or not. With a few splits the pipework becomes longer with more connections that you would need to make yourself to fit your house. And there's pressurised gas in it, so more chance of leaks. Might have max distances between splits back to the outdoor unit on DIY units. So the DIY element gets harder I guess.

But I'm deffo in the camp of not ruling out a DIY myself. If it came down to a costly home heatpump V a cheaper but lower performing COP on an air to air mini splits... Well, it's worth some number crunching

People say the downside is it can actually feel colder as the air is blowing over you. That cools us down of course (even when hot air). But I reckon I could live with that, just mind where you fit it so not over your head when sitting

That one certainly says it requires an engineer.

right last night was another reminder i need to do something about this... re the refrigerant in the unit linked on ebay.. that all comes pre filled?

I don't think this is the case. I've done a full retrofit of my home which would have been cold in winter and too hot in the summer. Now it's great in winter and so far, even with the rear being south facing it's not uncomfortable, open the windows first thing then the house stays at a nice temp. It could be the mechanical ventilation at play but in general the insulation should prevent massive swings in temp.

I got a vision 3.1. Great for AC and even better for heating in the winter. Just bore a couple of holes and mount it on an outside wall in the room you want heated/cooled. Ours was the kitchen. I was thinking of getting another one for heating the sitting room in the winter too because they are dirt cheap to run.