New Aircon Advice

[stament]

So, we need a new Aircon unit for our newly extended kitchen which is a bit of an L shape. Length is 7.3m and the width is 4.1m at the max point and 2.6m at the narrowest part. 

 

I've worked out the area to be 26 sqm. There are east facing windows but it's not that sunny there as there is a house 5 metres away.

 

Now, having read a lot of threads there seems to be differing advice as to the BTU size. I have also used calculators and they also came out different.

 

I am wondering whether I should get 18,000 or 24,000.  I've decided on  Daikin as that seems to be one of the top choices.

 

Any advice would be appreciated.

 

Cheers

 

 

 

 

 

 

[OneMoreFarang]

From my recent experience I agree with Daikin and 18k should do the job.

[Artisi]

Better to be at max capacity than oversized. 

[eisfeld]

15 minutes ago, Artisi said:

Better to be at max capacity than oversized. 

That used to be good advice when aircons were not using inverters. I don't think it's as easy as that anymore. "Oversized" is a fuzzy term because the more BTU the faster it can cool down the room from a hot state.

 

18k should be able to keep the room cool enough from the description of the OP. 24k will be able to cool it down faster but is not technically needed to keep the room at a reasonable temperature. 26sqm is fairly large for a kitchen so I assume OP also has a table for eating in there. If it was a living room with sun exposure due to lots of glass and where I spent a lot of time or wanted to cool it fast I'd go for the 24k option.

 

Daikin is a decent brand indeed.

[Mickeymaus]

In my experience far too many BTU will cool the room down more quickly. But since the compressor runs a shorter time it will do a very bad job when it comes to take out the moisture of the air. On the other hand a far too weak aircon will achieve the opposite - it will create air that is too dry. 

[stament]

35 minutes ago, Mickeymaus said:

In my experience far too many BTU will cool the room down more quickly. But since the compressor runs a shorter time it will do a very bad job when it comes to take out the moisture of the air. On the other hand a far too weak aircon will achieve the opposite - it will create air that is too dry. 

So what is best 18k or 24k? Presumably 21k which Daikin don't make ????

[TimeMachine]

I like to undersize a little as I am not hardly switching on an Aircon and don't need super cold. Inverter type a must nowadays they are more affordable. I'd rather choose a smaller btu inverter type than a bigger btu non inverter type.

Check out reviews on the models you have your eye on. I chose Hisense recently in Oz and all good after reading a lot of reputable website reviews.

 

[Mickeymaus]

If I understand you correctly you have 26 sqm. I have in two similar rooms conventional Daikin aircons with 3800 Watt what is about 13,000 BTU. For my situation this is more than enough. Of course it depends on the insulation of the room. If I buy an inverter I would take a little bit more BTUs. A friend of mine has in his condo in similiar rooms conventional aircons with 33,000 BTU. It is good for shock freezing but for nothing else. 

 

But again - this is my experience. I don't want to be guilty... Not that you sit in the too hot kitchen with many beer and think I could kill this Mickeymaus... In respect of Daikin - I will not buy this brand again. The white plastic is yellow now and the remote control displays get black. And the compressors are a little bit on the noisy side. But my aircons are old in the meantime and perhaps their products improved. Maybe Mitsubishi next time. Regarding kitchen - when you cook better switch it off.

 

If you buy an inverter aircon make sure that Geckos cannot get on the boards. A very unpleasant experience for the Gecko and often a very expensive one for you. 

 

[soi3eddie]

In my experience, Top range Daikin Inverters. 20% above size. Super quiet, extra efficient and cools down fast. Much less energy usage also. 

 

[stament]

Thanks all for the comments. So are we saying an 18k, 24k or 2 smaller ones? 

[stament]

10 hours ago, Artisi said:

Better to be at max capacity than oversized. 

Would that mean 18k is the max and the choice?

[stament]

6 hours ago, soi3eddie said:

In my experience, Top range Daikin Inverters. 20% above size. Super quiet, extra efficient and cools down fast. Much less energy usage also. 

 

So you mean go for what size?

[stament]

So far we have 2 votes for 18k from @OneMoreFarangand @eisfeld

 

Others haven't been specific in size recommendations. 

 

Any others care to choose?

[couchpotato]

18k inverter is what you need.

Can be Daikin or now many reputable brands have excellent inverter models.

Such as Mitsu, Panasonic, Carrier. Shop around for prices which includes installation.

Also remember a model which is easy to clean, as being in a kitchen the air will be much dirtier than a bedroom.

[OneMoreFarang]

1 hour ago, stament said:

So far we have 2 votes for 18k from @OneMoreFarangand @eisfeld

 

Others haven't been specific in size recommendations. 

 

Any others care to choose?

Some time ago when I ordered my ACs I had to decide if I just trust a company to recommend something or how should I buy.

I looked for online calculators. Most of them are simple, can they really be precise? And should we trust an AC company when they profit from selling bigger, more expensive ACs?

 

Then I looked some more, and I found a little more complicated calculators which included the size in sqm of the windows and the orientation to the sun of those windows. Ok, that's better.

 

But what I never found was any calculator with temperatures. What does it mean to have the correct size of an AC? Does it mean that that AC is able to cool down the room to maybe 24 degrees Celsius inside the room when it is outside 30 degrees? How about if I want a winter party and I want inside 18 degrees? And how about I want that in the worst part of the year with outside 40 degrees? 

I never found a calculator which gave me the choice of selecting my desired room temperature. And I never saw a calculator which asked me if I expect that the AC needs 5min or 30min to reach that desired temperature.

So it seems all those online calculators are not very precise.

 

My personal summary: Think how cold you want it and how fast. If you want it real fast real cold, then buy the 

max size model which any calculator suggests. And if you don't really care about too cold too fast then buy the minimum size recommended somewhere.

 

And be aware there is something like a too big AC. So don't just buy the biggest available. 

[EVENKEEL]

My living room is about 46 M and I installed 2 18,000 btu Daikans. One unit at a time is sufficient with a fan to help.

[KannikaP]

33 minutes ago, EVENKEEL said:

My living room is about 46 M and I installed 2 18,000 btu Daikans. One unit at a time is sufficient with a fan to help.

I have two 18k BTU Mitsus in my 40 sq mtr lounge. Was advised never to run only one as that will be running full 8o11ox and the other nothing. 4 x  Mr Slim Mitsus are 10 years old and apart from a starting capacitor in three of them, regular cleaning, no problems whatsoever. Mitsu Inverters next time for me.

[soi3eddie]

3 hours ago, stament said:

So you mean go for what size?

I went 20% above previously installed Daikin condensers and they fitted the old unit footprint exactly. The exterior compressors are bigger though. 

As for what size to go for; their are calculation charts (I beleive) that advise BTUs needed depending on room size, windows, insulation and whether the walls are in direct sun etc. These are all considerations of the cooling capacity needed. Switching to new inverters (from 2009 standard types) was such a good move for me in all ways, except initial cost being more than standard types. I think nowadays most units are inverters anyway. My electricity bill dropped massively and the cooling is better. 

 

[Mickeymaus]

I have an undersized conventional unit in an about 50 sqm room. It is also only about 13,000 BTU like in the two smaller rooms. It was installed in the condo already. The effect is that it takes a lot of moisture out of the air but cooling is very slow. It helped me to discover something.

 

For me not the temperature is so much the problem but the humidity. So when the air is dry enough I switch the aircons off and switch on a fan. Perfect and saves a lot of electricity. In my accommodations before I always tried to reduce the temperature to at least 26 degrees. But the real problem for me was the humidity.

[mudcat]

The Daikan inverter unit we have has Powerfull setting to get the temperature down sooner.  I believe this forces the compressor to run at maximum.  Check to see if the model you are considering has a similar option.

[Mickeymaus]

41 minutes ago, soi3eddie said:

I went 20% above previously installed Daikin condensers and they fitted the old unit footprint exactly. The exterior compressors are bigger though. 

As for what size to go for; their are calculation charts (I beleive) that advise BTUs needed depending on room size, windows, insulation and whether the walls are in direct sun etc. These are all considerations of the cooling capacity needed. Switching to new inverters (from 2009 standard types) was such a good move for me in all ways, except initial cost being more than standard types. I think nowadays most units are inverters anyway. My electricity bill dropped massively and the cooling is better. 

I'm considering switching to inverters. But for me it is very important that the air conditioners reduce the humidity. How about your inverters. Are they doing a good job reducing humidity? How is your experience compared to your old conventional aircons?

[ozimoron]

14 minutes ago, Mickeymaus said:

I'm considering switching to inverters. But for me it is very important that the air conditioners reduce the humidity. How about your inverters. Are they doing a good job reducing humidity? How is your experience compared to your old conventional aircons?

In that respect there is no difference.

[soi3eddie]

38 minutes ago, Mickeymaus said:

I'm considering switching to inverters. But for me it is very important that the air conditioners reduce the humidity. How about your inverters. Are they doing a good job reducing humidity? How is your experience compared to your old conventional aircons?

Can't really say about humidity except that they just seem to make the rooms much more comfortable. I should add that I rarely suffer from heat (which is one reason I like Thailand so much). Here in my Bangkok condo, I normally don't turn on A/C until dusk when I close my balcony doors.

 

[sometimewoodworker]

15 hours ago, stament said:

So what is best 18k or 24k? Presumably 21k which Daikin don't make ????

At 18k you are at at just under 700 BTU/sqm at 24 you are a little over 900 BTU/sqm

since the prices are little different and you are getting an inverter go for the larger unit.

 

The comments of cooling too quickly are confusing the non inverters performance where cooling too quickly would not decrease humidity but since the inverter doesn’t stop running this is no longer true.

 

in the past a slightly under spec AC was significantly better than one that was over specified. Because the humidity control was significantly better. This is no longer true with inverters (with in reason).

 

So buy the bigger unit, it will cope with anything you do, cool quickly and have as good humidity control as the smaller unit. The smaller unit may be enough or it may not specially after a couple of years when it drops in efficiency.

[sometimewoodworker]

3 hours ago, Mickeymaus said:

I'm considering switching to inverters. But for me it is very important that the air conditioners reduce the humidity. How about your inverters. Are they doing a good job reducing humidity? How is your experience compared to your old conventional aircons?

I’ve had both a slightly undersized conventional unit with a noisy ceiling fan, a slightly undersized inverted with a silent fan and have now swapped that one into a room that had no ac and have an oversized inverter in the same room, it still has a silent fan.

All three units controlled humidity well, the 2 smaller units took quite a while to bring the temperature down, the big inverter cools quickly but is very slightly noisier than the small one. I use the silent fan with the inverters as the room temperature can be higher and still be comfortable. The fan is a MrKen DC fan so has 6 speeds No. 1 or 2 is usually enough.

 

My preference would be a silent AC with a silent fan but the Daikin is not silent, it is very very quiet but the Mitsubishi is silent. The noise level will depend on the model you get AFIK they are similar 

[Encid]

6 hours ago, KannikaP said:

I have two 18k BTU Mitsus in my 40 sq mtr lounge. Was advised never to run only one as that will be running full 8o11ox and the other nothing. 4 x  Mr Slim Mitsus are 10 years old and apart from a starting capacitor in three of them, regular cleaning, no problems whatsoever. Mitsu Inverters next time for me.

Mitsubishi Mr Slim inverters get my vote too... very quiet operation and very effective temperature reduction and control.

 

21 hours ago, stament said:

So, we need a new Aircon unit for our newly extended kitchen which is a bit of an L shape. Length is 7.3m and the width is 4.1m at the max point and 2.6m at the narrowest part. 

 

I've worked out the area to be 26 sqm.

For that area I'd recommend a 24K BTU centrally located ceiling cassette unit, however since you have an L-shaped area to cool perhaps you would be better off with two wall mounted units... one at either end of the L.

Then you could probably get away with a 9K BTU unit and a 12K BTU unit.

 

Have a look at the Mitsubishi inverter range of AC here.

[Migz007]

When determining the appropriate BTU size for an air conditioning unit, it's important to take into account several factors in addition to the size of the room, such as the level of insulation, the number of windows, and the height of the ceiling. However, as a rough estimate, a room with an area of 26 sqm would typically require an air conditioner with a cooling capacity of around 9,000-12,000 BTUs.

 

Given that your kitchen has some east-facing windows and there is a house located 5 meters away, it's possible that the amount of heat entering the room through the windows could be reduced. However, the L-shape of the room and varying ceiling height could affect the cooling efficiency of the air conditioning unit.

 

Based on the size of the room and the varying advice on BTU size, it may be best to consult with an HVAC professional to get a more accurate estimate of the appropriate BTU size for your kitchen. Additionally, Daikin is a well-regarded brand, and it's important to choose an air conditioner that has a high Energy Efficiency Ratio (EER) to minimize energy consumption and reduce your energy bills.

[sometimewoodworker]

27 minutes ago, Migz007 said:

it may be best to consult with an HVAC professional to get a more accurate estimate of the appropriate BTU size for your kitchen.

5555555. Good luck with that idea.

[stament]

Will the airflow go round the L shape if the Aircon is placed at the top of the L shape pointing towards the bottom of the L if you get my drift...????

 

What will happen when it hits the far wall?

[KhunLA]

On 1/31/2023 at 4:57 AM, stament said:

So far we have 2 votes for 18k from @OneMoreFarangand @eisfeld

 

Others haven't been specific in size recommendations. 

 

Any others care to choose?

13k should be more than enough IMHO.  Unless total krap build material wise and sun exposed.

 

We have a 13k in the bedroom, 23m², and could easily get by with 9k BTU unit.  House good build material, insulated block & roof/ceiling.  Actually gets damn chilly.

 

Since a kitchen and heating up things, 13k should do.  18k being overkill IMHO.  Especially since exhaust fan will be taking most of the heat out.

 

We have the 13k, and a 24k BTU unit, which they condition 105m² daily, and do it quite well.  Bedroom & main room, usually leave bedroom door open, though neither room needs supplementing from the other.

 

Mitsubishi Inverter fan myself.