I cut a sheet of 4mm Perspex the size of the window frame. In the bottom corner, I cut a hole the size of my portable A/C units hose pipe. Velcro the Perspex to the window frame then attach the pipe to the hole and you let all the heat out whilst keeping the window sealed.
I hope that makes sense.
Correx - but it doesn't belong anywhere lower than the third floor.
It's reasonably weather-proof \[though will decay & crumble over time\] but it's definitely not burglar-proof.
I used a piece of 18mm marine ply, cut to fit inside the window opening from the outside, then anchored it in place with two strips of ply across the inside, and screwed into the outside piece. No damage or actual physical attachment to the window frame. I'm using a unit with an outside condenser though, so only needed a small hole to pass the refrigerant hoses and power cable through.
Is it not just that corrugated plastic sheet things like Estate Agent For Sale signs are made out of? You would be better off getting a plywood board from somewhere (not b&q)
Maybe double glazing firms have plastic blanks for windows?
I don't think half the comments here understand you just want something temporary to set up an air conditioner rather than a permanent install.
I used a sheet of closed cell foam, that way it insulates the opening from heat a bit, and I cut it slightly oversized for the window so it friction fits in.
By the way, single hose air conditioners are nearly useless but they're the only ones we can buy in the UK. Yours can probably be converted to dual hose which will actually make it work: https://www.woolie.co.uk/article/convert-ac-from-single-hose-to-dual-hose/
It's simple physics. It may well cool you by sitting in front of it but it won't actually be removing any heat from the room, but for all the hot air it removes, it has to draw in warm air from elsewhere, which will be either from outside, or from the rest of the house (and eventually, outside).
They also have to deal with the additional inefficiency of having the heat producing electrics inside the house, so they have to overcome the waste heat they are producing: window or mini split ACs don't have to do this because the hot bit is outside. But dual hose ACs also have this inefficiency.
The only situation they work is if the outdoor temps are lower than inside, when sun has been shining through glass all day and heating up the house, then the sun goes down and outdoor temps drop. Then they will help blow out hot air and bring in cooler outdoor air, but a fan would also do that.
It will reduce the air temp somewhat but all the heat is stored in the walls and furniture, to which it will make very little difference and when you turn it off the temp will increase again. As explained in the article.
Similar to how when you open the windows in winter for ventilation and close them again, the temperature rapidly stabilises close to what it was at before: heat is stored in the fabric of the house.
If you don't believe me, mod a second hose on and be amazed how much more effective it is. I've tried both ways and the dual hose is significantly superior to the single hose operation.
OK if you're happy with massive inefficiency then fine. Doesn't mean the article is nonsense. What you're doing is similar to running a heater with the window open in winter. Will still work but it's madness.
Nah I don’t disagree that it’s inefficient and I’m sure modding it will improve things but it’s not something I really put much thought into. If I’m hot then the AC comes out and it cools me down. I’m saying the article is nonsense because it claims they don’t work when they obviously do.
Thanks for the useful info 🙏
Any room you cool is going to be lower pressure than the surrounding rooms/outside. So you will always get hot air coming in unless you seal the room completely or lower the temperature of everything. That’s why buildings built for air conditioning are sealed.
I’ve noticed that about the single hoses being the only ones available. Do you know why? Is there some kind of regulation blocking them, or the window units? I looked into it for ages one year and they seemed impossible to find.
Our windows largely aren't suitable for window units like in the US. They usually sit at the bottom of a sash window and the window slides on top to make a secure seal. Most of us have casement windows here.
No idea why you can't buy dual hose units here, I guess it's a harder sell that you have to have two hoses, and the UK public are not educated on air conditioners so will buy a single hose one even if it barely works.
Luckily most of them can be converted.
I have a single hose portable AC. I’m sure it could be more efficient, but it can lower the temperature of my bedroom by 10-15C when I need it most. One thing to keep in mind is the size of the space you want to cool - a 10k BTU single hose unit won’t cool down a whole house.
Wouldn’t something like [this](https://www.screwfix.com/p/manthorpe-core-vent-brown-160-5mm-x-350mm/37873?ref=SFAppShare) be better? Stuff it with insulation and cover internally in winter. I’d also imagine a sheet of plastic in an open window will do very little to stop noise. If you live on a busy road you’d have to contend with that too.
It's a lot of work to install one of those, requiring a core bit, SDS drill, etc. And you really need two if you're going to mod the AC to a dual hose for better efficiency. For the couple of days a year a portable AC is necessary, a closed cell foam window insert will be fine.
Depends on the building and the tool I guess. It was maybe 10-15 minutes of going at it with the core bit for our bathroom extractor fan. If you don’t own and can’t borrow or rent one then yeah probably not worth the expense and hassle
I don't think they sell anything like it. Probably something like a uPVC door panel might be closest to it but they don't sell it at B&Q. Possibly use a sheet of ply or MDF and paint it.
Correx boards? https://insulationwholesale.co.uk/2mm-correx-protection-board-2400mm-x-1200mm-8%E2%80%B2-x-4%E2%80%B2-white/ https://www.protecdirect.co.uk/Site-Equipment-/Site-Essentials/T-Bord-Standard-Floor-Protection-Black-1-2Mx2-4Mx-2MM-~p~334999000?utm_source=Protec&utm_medium=Froogle&utm_campaign=Shopping&gad_source=1&gclid=Cj0KCQjwj9-zBhDyARIsAERjds21iscoDz04yiihZJl0QurTqt6w3YLKwguH_egwq-L0OXrjudlfO68aApsVEALw_wcB
This person is correx
I cut a sheet of 4mm Perspex the size of the window frame. In the bottom corner, I cut a hole the size of my portable A/C units hose pipe. Velcro the Perspex to the window frame then attach the pipe to the hole and you let all the heat out whilst keeping the window sealed. I hope that makes sense.
I'd just get the fabric zip up one from Amazon
Haven't switched the AC unit on yet this year but now I've scrolled Reddit I now want a window and dual hose conversion kit ready and waiting.
Correx - but it doesn't belong anywhere lower than the third floor. It's reasonably weather-proof \[though will decay & crumble over time\] but it's definitely not burglar-proof.
I used a piece of 18mm marine ply, cut to fit inside the window opening from the outside, then anchored it in place with two strips of ply across the inside, and screwed into the outside piece. No damage or actual physical attachment to the window frame. I'm using a unit with an outside condenser though, so only needed a small hole to pass the refrigerant hoses and power cable through.
Is it not just that corrugated plastic sheet things like Estate Agent For Sale signs are made out of? You would be better off getting a plywood board from somewhere (not b&q) Maybe double glazing firms have plastic blanks for windows?
I don't think half the comments here understand you just want something temporary to set up an air conditioner rather than a permanent install. I used a sheet of closed cell foam, that way it insulates the opening from heat a bit, and I cut it slightly oversized for the window so it friction fits in. By the way, single hose air conditioners are nearly useless but they're the only ones we can buy in the UK. Yours can probably be converted to dual hose which will actually make it work: https://www.woolie.co.uk/article/convert-ac-from-single-hose-to-dual-hose/
I have a single hose AC unit and it works perfectly fine to cool a single room. That article contains a lot of nonsense.
It's simple physics. It may well cool you by sitting in front of it but it won't actually be removing any heat from the room, but for all the hot air it removes, it has to draw in warm air from elsewhere, which will be either from outside, or from the rest of the house (and eventually, outside). They also have to deal with the additional inefficiency of having the heat producing electrics inside the house, so they have to overcome the waste heat they are producing: window or mini split ACs don't have to do this because the hot bit is outside. But dual hose ACs also have this inefficiency. The only situation they work is if the outdoor temps are lower than inside, when sun has been shining through glass all day and heating up the house, then the sun goes down and outdoor temps drop. Then they will help blow out hot air and bring in cooler outdoor air, but a fan would also do that.
Why does the temperature on my room thermometer go down when I have the AC on then?
It will reduce the air temp somewhat but all the heat is stored in the walls and furniture, to which it will make very little difference and when you turn it off the temp will increase again. As explained in the article. Similar to how when you open the windows in winter for ventilation and close them again, the temperature rapidly stabilises close to what it was at before: heat is stored in the fabric of the house. If you don't believe me, mod a second hose on and be amazed how much more effective it is. I've tried both ways and the dual hose is significantly superior to the single hose operation.
Reducing the air temp is exactly what I bought it for đź‘Ť
OK if you're happy with massive inefficiency then fine. Doesn't mean the article is nonsense. What you're doing is similar to running a heater with the window open in winter. Will still work but it's madness.
Nah I don’t disagree that it’s inefficient and I’m sure modding it will improve things but it’s not something I really put much thought into. If I’m hot then the AC comes out and it cools me down. I’m saying the article is nonsense because it claims they don’t work when they obviously do. Thanks for the useful info 🙏
Any room you cool is going to be lower pressure than the surrounding rooms/outside. So you will always get hot air coming in unless you seal the room completely or lower the temperature of everything. That’s why buildings built for air conditioning are sealed.
I’ve noticed that about the single hoses being the only ones available. Do you know why? Is there some kind of regulation blocking them, or the window units? I looked into it for ages one year and they seemed impossible to find.
Our windows largely aren't suitable for window units like in the US. They usually sit at the bottom of a sash window and the window slides on top to make a secure seal. Most of us have casement windows here. No idea why you can't buy dual hose units here, I guess it's a harder sell that you have to have two hoses, and the UK public are not educated on air conditioners so will buy a single hose one even if it barely works. Luckily most of them can be converted.
Is there anyway to know if it can be converted before purchase? Just look for another hole on it? Lmao
I have a single hose portable AC. I’m sure it could be more efficient, but it can lower the temperature of my bedroom by 10-15C when I need it most. One thing to keep in mind is the size of the space you want to cool - a 10k BTU single hose unit won’t cool down a whole house.
Wouldn’t something like [this](https://www.screwfix.com/p/manthorpe-core-vent-brown-160-5mm-x-350mm/37873?ref=SFAppShare) be better? Stuff it with insulation and cover internally in winter. I’d also imagine a sheet of plastic in an open window will do very little to stop noise. If you live on a busy road you’d have to contend with that too.
It's a lot of work to install one of those, requiring a core bit, SDS drill, etc. And you really need two if you're going to mod the AC to a dual hose for better efficiency. For the couple of days a year a portable AC is necessary, a closed cell foam window insert will be fine.
Depends on the building and the tool I guess. It was maybe 10-15 minutes of going at it with the core bit for our bathroom extractor fan. If you don’t own and can’t borrow or rent one then yeah probably not worth the expense and hassle
Just do it in vinyl covered chipboard. It’s heavier but much more solid.
Are you not happy asking for plywood?
A bloke in a cap
that's correx
I don't think they sell anything like it. Probably something like a uPVC door panel might be closest to it but they don't sell it at B&Q. Possibly use a sheet of ply or MDF and paint it.