yeah we are struggling with insulation in a downstairs front lounge - there are 4 air bricks and i am fairly certain no insulation under the floorboards - i am thinking of doing something about this this coming summer...
Split Air con
- Thread starter YoungBlood
- Start date
If your house is reasonably well insulated, you also don’t need a massive unit either. The impression I get from the sector is similar to heating, no one bothers to do a heat loss/gain calculation and they tend of approach it by just putting in a big unit regardless of how overkill it probably is and inefficiently it will run in the real world.
When I had an air to water heat pump quote done with a proper heat loss calculation, they recommended a unit with a 6kw output to run the entire house. It’s nothing really.
When I had an air to water heat pump quote done with a proper heat loss calculation, they recommended a unit with a 6kw output to run the entire house. It’s nothing really.
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Associate
Yup, I installed 3 units in 2020 and did a heat loss calc myself. 2 units in a new extension, well insulated, and the smallest 2kw units were more than we needed for each room.
Associate
Yup, just a little. Just found the spreadsheet, both rooms needed a total of about 600W on the coldest days, so 4kW just about does it. But that great as it means it barely runs and ticks over without noticing its even on.
Makes sense. The reason I raised the issue of having units which are too powerful is that they can't ramp down low enough once the room is close to temperature. They then start cycling and that constant on, off, on, off is what tanks the efficiency on a heat pump. It's so much more cost effective to have something correctly sized both installation and running costs.
Someone licking their finger, sticking it in the air followed by sucking air in between their teeth and suggesting X KW may not have considered everything they need to. The exactly the same principle applies to condensing boilers which is why hardly anyone actually gets the 90+% efficiency they quote, many them are massively oversized and/or they not connected to appropriately sized rads.
Someone licking their finger, sticking it in the air followed by sucking air in between their teeth and suggesting X KW may not have considered everything they need to. The exactly the same principle applies to condensing boilers which is why hardly anyone actually gets the 90+% efficiency they quote, many them are massively oversized and/or they not connected to appropriately sized rads.
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Soldato
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ok, silly question.....
In a three storey house, where 2 bedrooms are on the top floor, and three on the middle, if you only put aircon in the top two bedrooms, will the rest of the house feel cooler?
Last summer the top floor was a nightmare
In a three storey house, where 2 bedrooms are on the top floor, and three on the middle, if you only put aircon in the top two bedrooms, will the rest of the house feel cooler?
Last summer the top floor was a nightmare
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I think you'd be asking a lot for units in two bedrooms to affect three other bedrooms on a different floor. And you'd need to keep the doors open on all five to have any hope at all.
During the heatwave last year, when we only had air con in the lounge, I tried leaving the door to the lounge open and even pointing a fan from that door and up the stairs. It made a noticeable difference to the hall, and slight difference to the landing. But to the upstairs rooms - hardly anything.
The problem is that it attained the temperature it was aiming for in the lounge, and turned itself down to only just ticking over. And the circulation of air between that room and the others wasn't sufficient to share that reduction in temperature to any great degree.
Your situation might work a little better because you're trying to get the cool air lower, rather than higher like I was. So convection will be working in your favour.
During the heatwave last year, when we only had air con in the lounge, I tried leaving the door to the lounge open and even pointing a fan from that door and up the stairs. It made a noticeable difference to the hall, and slight difference to the landing. But to the upstairs rooms - hardly anything.
The problem is that it attained the temperature it was aiming for in the lounge, and turned itself down to only just ticking over. And the circulation of air between that room and the others wasn't sufficient to share that reduction in temperature to any great degree.
Your situation might work a little better because you're trying to get the cool air lower, rather than higher like I was. So convection will be working in your favour.
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This is what I did. Lounge door open and fan blowing into dining room to spread the cool air around. @TheOracle It will help keep things a bit cooler, but you're talking small degrees and if it is roasting that won't be enough.
I have ducted system upstairs and if I only had this on with upstairs doors all open it didn't really affect downstairs much at all.
Need to consider an airconditioning solution for a garden office I'm having built - c60m3 volume, so I'm guessing around 12000 BTU, needs to also be capable of heating during the winter months.
Google has been relatively helpful, but would appreciate being pointed in the right direction by people more in the know!
Google has been relatively helpful, but would appreciate being pointed in the right direction by people more in the know!
Soldato
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Just get a 2.5 or 3.5 wall mount back to back daikin or mitsi electric (much prefer the latter personally.).
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Largely I would say no, not very effective at all outside the room the unit is in. You can get something by running your upstairs units silly cold and using fans but even then you'll feel hardly any effect downstairs compared with the room it's in. If you want to cool downstairs then 100% get wall units down there too.
Soldato
I saw Boxt do a AC service. Sadly it's very minimal for customising the install. Are there any similar nationwide services?
I really don't have the time or energy to be finding local tradesmen given the past 2 years of trying to get literally anything done. Such a headache.
I really don't have the time or energy to be finding local tradesmen given the past 2 years of trying to get literally anything done. Such a headache.
Very quickly reaching the point I wish we had A/C upstairs. Room with the gaming PC is reaching 23C+ every day now. Window open doesn't often help that much, plus it's letting in noise, insects, and pollen. Our main bedroom, which is south-facing, is also starting to heat up a little bit too much even with the blinds shut. Damn our good insulation and solar windows 
Man of Honour
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Very quickly reaching the point I wish we had A/C upstairs. Room with the gaming PC is reaching 23C+ every day now. Window open doesn't often help that much, plus it's letting in noise, insects, and pollen. Our main bedroom, which is south-facing, is also starting to heat up a little bit too much even with the blinds shut. Damn our good insulation and solar windows
Best thing I ever did. Haven’t needed it quite yet, but not too far off I suspect. I think our neighbour is going to install it now also.
In the hot days last summer the blinds did nothing.
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Yea if they're on the inside they'll do nothing, as the heat is already "through" the window. You need external shading to stop direct sunlight on the windows to stop it.
Soldato
Anyone got a ballpark cost for a 6 unit split system? 4 bed house, plan to have 3 upstairs and 3 downstairs Thanks
Soldato
Ballpark....I paid £4.5k in total for 3 indoor units and 2 outdoor (done in 2 waves). So approx £1.5k per indoor unit as a guide. I suppose the fewer outdoor unit's you have the cheaper it gets but I would assume you need at least 2 for 6 indoor.
Man of Honour
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Ours were about 2.5k per unit. London prices, higher end units. You’ll probably need two outdoor units.