Portable air conditioners any good?

[Lacessit]

For the area described, a 9000 BTU aircon will be more than adequate. I have a Samsung 9000 BTU unit which is very effective in cooling 36 sqm. Most sales people attempt to sell higher BTU units to get a higher commission. Good roof and wall insulation helps aircons considerably.

Humidifier/ice coolers are a waste of time and money in Thailand. They only work in desert climates, where the RH is about 10%. At 80-90% RH, it's like being in a sauna.

It always amuses me to see such units on display in airconditioned shopping malls. They are reprocessing air that has been dehumidified, of course they will feel cooler. Duh.

[millymoopoo]

22 hours ago, Kwasaki said:

There are 2 types one you still have to set up with pipes in & out windows and set up a drip tray. 

The other is having a ice storage area to blow cold air but they use aot of ice. 

The first it a compressor type A/C, same principle as wall units.
The second is a glorified evaporative cooler, AKA swamp cooler, when they melt all the ice they become swamp coolers. And yes, use heaps of ice.

And whilst the portable A/C units work just OK because they use the same principle as split (wall) systems, they too have a fault.
For want of a more technical explanation there are two sides to refrigerated split and portable A/C, a cooling and a heating (it's the way this type of refrigeration works) the room air is drawn into the cool side, passed through and exits much more cooler (that's the cassette on the bed/lounge room wall with a split system).
With the heat side it's the same, air drawn in passes through and exits much hotter. In a split (wall) system all this side occurs outside (it's the big box with the round fan found on walls/roofs outside.

The problem with portable A/Cs is they draw the air in for both the cooling and heating side from within the room, the exhaust from the heating is then ducted via flexible tube to the outside, usually through a window. And in that is where the problem is, as they are constantly drawing air in for both cooling and heating sides from within the room, the room is always at negative atmospheric pressure, thus drawing hot air in from all the cracks, gaps, open doors and windows greatly reducing the efficiency.

The solution is to duct the heat inlet to outside as well as the exhaust, with some work we managed to this and instantly the portable unit became as efficient as a wall unit, just a tad noisier.

BTW the more humid the relative humidity the less effective evaporative (swampies) units become.

Another alternative to look at when building a new house is a labyrinth of large poly pipes under the house, in the ground, passing air through the pipes into the house helps bring the house to ground temperature which is usually 10c below ambient.

[lopburi3]

4 minutes ago, millymoopoo said:

The solution is to duct the heat inlet to outside as well as the exhaust, with some work we managed to this and instantly the portable unit became as efficient as a wall unit, just a tad noisier.

The logic is to keep cooling the already cooled air.  That is why even window AC units draw almost all air to be cooled from inside the room.  In a split system it is 100%.  No air leaves - AC converts cold gas to hot and that is cooled on outside and piped back in as gas to cool more inside air in a cycle.  This can, and is, done by use of cold water in factory settings.  The water flows - not the air.  You just have air cooled on one side and the water on the other.  The air stays in their respective locations.

[spidermike007]

No. Anyone I know who has spent money on one, has lived to regret the decision. Better to invest in a good inverter AC unit. I have an 18,000 BTU unit that is going on 13 years old, it's second home, and is still going strong. I get it thoroughly cleaned every 6 months. Same for all the units. A real trick to both longevity, and cleaner lungs. It is a Samsung inverter, by the way. And I recently bought a Panasonic inverter. Amazing quality, but more expensive. Worth it. 

Edited March 20, 2021 by spidermike007

[Aomelia]

22 hours ago, lopburi3 said:

15,000 is more than most wall units would cost installed and you have good cooling.  Portable requires vent outside cooled area to cool so not really portable and likely to be very noisy.  ICE flow coolers make no sense in Thailand humidity.  As far as inverter units they are not much more, if any, than the older versions today and can often save you money in operating expense.  They are still less than 15k as you should not need more than 9-13k btu for a bedroom (I use 9 for 26sm and works fine) unless you require tour bus temp.  

I got mine for 8,000 worked great but pain in butt with exhaust hose out windows or wherever 

[Kwasaki]

1 hour ago, millymoopoo said:

The first it a compressor type A/C, same principle as wall units.
The second is a glorified evaporative cooler, AKA swamp cooler, when they melt all the ice they become swamp coolers. And yes, use heaps of ice.

And whilst the portable A/C units work just OK because they use the same principle as split (wall) systems, they too have a fault.
For want of a more technical explanation there are two sides to refrigerated split and portable A/C, a cooling and a heating (it's the way this type of refrigeration works) the room air is drawn into the cool side, passed through and exits much more cooler (that's the cassette on the bed/lounge room wall with a split system).
With the heat side it's the same, air drawn in passes through and exits much hotter. In a split (wall) system all this side occurs outside (it's the big box with the round fan found on walls/roofs outside.

The problem with portable A/Cs is they draw the air in for both the cooling and heating side from within the room, the exhaust from the heating is then ducted via flexible tube to the outside, usually through a window. And in that is where the problem is, as they are constantly drawing air in for both cooling and heating sides from within the room, the room is always at negative atmospheric pressure, thus drawing hot air in from all the cracks, gaps, open doors and windows greatly reducing the efficiency.

The solution is to duct the heat inlet to outside as well as the exhaust, with some work we managed to this and instantly the portable unit became as efficient as a wall unit, just a tad noisier.

BTW the more humid the relative humidity the less effective evaporative (swampies) units become.

Another alternative to look at when building a new house is a labyrinth of large poly pipes under the house, in the ground, passing air through the pipes into the house helps bring the house to ground temperature which is usually 10c below ambient.

You give a good description of the portable a/cons for OP. 

I had both, one we still have it's OK packing with blocks of ice at times when we sit outside on warm evenings.

The one like wall a/con we gave away it used a lot of power it was better than nothing at the time,  it was bought initially to move around in downstairs rooms but was not to be as portable as we first thought.

[Tropposurfer]

Portable aircon is only efficient in small spaces and will cost you a bomb to run. If you can run one and then save for either ducted or split system then go for it.

[AgMech Cowboy]

Hi cooked, I'm not familiar with the 'portable' compressor A/C (and i'm not reading all the responses here either).  I just glanced through the HomePro offerings and you can get a Sharp wall A/C 12300 BTU inverter installed for 12,990 baht.

[joe999]

If your budget is around 15k, with some search and luck, you'll find good deals online. Got a 12000BTU LG inverter 2 years ago at 50% off, 10.5 k. Another 3k for installation. 9000 BTU should be ok for you, you should be able to find something below 10k. I hear that some of the chinese brands are not too bad, TCL, Haier...

At that time was considering portable unit, after some research, I concluded that this would have been a <deleted> choice.

[xylophone]

5 minutes ago, joe999 said:

I hear that some of the chinese brands are not too bad, TCL, Haier...

I hadn't heard of the TCL air cons before, although their TV sets are prevalent in this country, and a review of these TVs against other major brands came out very favourably indeed.

A friend had Haier air cons installed in her business and rates them very highly.
 

[damen]

Portable Aircon will only be able to cool directly from the blower. It will not be able to cool down the whole room. I don't think you want this. I regret buying mine, total waste of money. And noisy as hell. 

 

And 15,000 baht is too expensive, I bought mine new (9,000Btu) for 6,000 baht in Tesco lotus. And they take lots more electricity compared to the usual wall mount kind. 

 

I suggest op to buy a second-hand wall mount air-con(now you should be able to find a relativity new, mint condition kind), I believed you can find in FB marketplace from the range of 2,000 baht to 6,000 baht. Installation usually costs 1,500 baht to 2,000 baht. 

 

If Op has a budget of 10,000 Baht to spare. You can buy new aircon in Shopee at around 7,000 baht then find your local aircon company for installation. Defnelly lower then 10,000 baht. 


https://shopee.co.th/การันตีถูกที่สุด!!-แอร์ผนัง-TCL-รุ่นธรรมดา-รุ่น-Miracle-Series-(ราคาไม่รวมติดตั้ง)-i.98523523.5728375525

[adexbu]

so crazy that some people still dont know how stupid krap these machines are.

anybody with half a brain will try to understand how a real aircon works and understand how these useless mobile "aircons" do not work...

 

[Dazinoz]

58 minutes ago, adexbu said:

so crazy that some people still dont know how stupid krap these machines are.

anybody with half a brain will try to understand how a real aircon works and understand how these useless mobile "aircons" do not work...

 

Well obviously you don't know either. A mobile air conditioner works the same as a split air conditioner, i.e. a refrigeration cycle. A mobile air cooler that you add water and/or ice to do not work. Both mobile coolers and air conditioners exist.

[MarleyMarl]

Noisy, low powered, waste of time and money from my experience.

[Aomelia]

I just went to Central Plaza Udon some guy on upper floor had a row of them on sale outside shop 1900b to 4700 b about 8 models , these our portable models check Makro and Home Pro also I bought one years ago 8,000 b looks like they have come down a lot 

[Yellowtail]

On 3/19/2021 at 4:30 PM, lopburi3 said:

And from USA that is something as many still use those noisy wall/window AC units which most people here gave up on decades ago.   Yes I know many places have central AC these days but this has it's own issues trying to move air through doors/ducts and huge blowers.  Wall split system is something that works well where instillation work price is reasonable, as here.

Mini and multi-spits are gaining popularity in the US residential market, but they are generally not suitable for commercial where codes which often mandate a minimum (often 10%)  amount of fresh air be introduced into the system continuously.

I have a friend in SoCal that just had a new Daiken multi-split unit installed in his home. I think it has two nines, a twelve and a twenty-four. It was a nice clean installation,  and he seems to love it. I'm really surprised the multi-splits have not caught on more here. Kind of the best of both worlds. The splits (and window/wall units) in the US are generally configured such that they provide heat in the winter as well.

I have six split units here (one cassette and five wall units) and I think they are great, but they are absolutely not not better, quieter, more effective, safer or cheaper to operate than a quality central unit.  

Incidentally, most hotels and motels in the US have wall mount heat & cool units, they are generally quiet, efficient, easy to maintain and cost effective. 

[lopburi3]

6 minutes ago, Yellowtail said:

Mini and multi-spits are gaining popularity in the US residential market, but they are generally not suitable for commercial where codes which often mandate a minimum (often 10%)  amount of fresh air be introduced into the system continuously.

I have a friend in SoCal that just had a new Daiken multi-split unit installed in his home. I think it has two nines, a twelve and a twenty-four. It was a nice clean installation,  and he seems to love it. I'm really surprised the multi-splits have not caught on more here. Kind of the best of both worlds. The splits (and window/wall units) in the US are generally configured such that they provide heat in the winter as well.

I have six split units here (one cassette and five wall units) and I think they are great, but they are absolutely not not better, quieter, more effective, safer or cheaper to operate than a quality central unit.  

Incidentally, most hotels and motels in the US have wall mount heat & cool units, they are generally quiet, efficient, easy to maintain and cost effective. 

There is little need for overly expensive heating from dual units here - just not cost effective at all.  As for air exchange do not believe that is a specific AC requirement  and split systems are the same as chiller units used for commercial cooling expect they use gas rather than water for heat exchange and do not have any 10% air flow.  Believe that would be entirely separate system for most buildings.  

[Yellowtail]

1 minute ago, lopburi3 said:

There is little need for overly expensive heating from dual units here - just not cost effective at all.  As for air exchange do not believe that is a specific AC requirement  and split systems are the same as chiller units used for commercial cooling expect they use gas rather than water for heat exchange and do not have any 10% air flow.  Believe that would be entirely separate system for most buildings.  

Yes, well most areas in the US do require heat, and having a split unit work as a heater/heat-pump does not increase the cost significantly. There are (I believe) some units available here the offer heat as well. 

I was not wondering why units with heat are not more popular here, but rather why multi-spit units (one condenser, multiple evaporators) were not offered here. That units in the US generally heat as well is incidental. 

Not sure what you mean in your second sentence. Anytime a code mandates fresh air be introduced, a mini-split system will not satisfy the code by itself and a secondary make-up-air system has to be installed. While these are inexpensive from an installation standpoint, they can be very expensive operationally. This is one reason they can be less desirable than "central" systems.

 

[RocketDog]

On 3/19/2021 at 5:46 PM, Kwasaki said:

We have small one which we put crushed ice in and with doors and windows open its cooler than just a fan.

Of course it cost something to make or buy ice. If you buy the ice it has to be stored in a freezer. Cost of the freezer and it's operation? 

Net savings? Pretty low I'm guessing. Not to mention the time and mess of refilling them and dumping the water. 

They are just toys in my opinion, as are evaporative coolers which simply do not work with most of Thailand having high humidity. 

Mechanical air cooling is the only thing feasible here. 

But if it works for you that's all that matters. 

[Chongalulu]

In the very long run the quality and longevity of a proper Mitsubishi inverter unit will pay off best. That brand is regarded by professional fitters is one of the best. Had a few units in our house for around 9 years with little problem apart from servicing. So last year for another house went for the latest Mitsubishi inverter unit circa 25k. Whisper quiet and efficient and expect it to be there 10 years later. 

[Kwasaki]

6 minutes ago, RocketDog said:

Of course it cost something to make or buy ice. If you buy the ice it has to be stored in a freezer. Cost of the freezer and it's operation? 

Net savings? Pretty low I'm guessing. Not to mention the time and mess of refilling them and dumping the water. 

They are just toys in my opinion, as are evaporative coolers which simply do not work with most of Thailand having high humidity. 

Mechanical air cooling is the only thing feasible here. 

But if it works for you that's all that matters. 

Well on reflection there not really air-cons as such there fan coolers and have there uses.

As I said we use it outside mostly now as well not so much inside and they are cooler that a fan.

Our combined household fridge/freezer it is big enough to hold blocks of ice that fit in the fans ice compartment.

You get a blue thing you can put in freezer but we use block ice that we form ourselves.

[Kwasaki]

38 minutes ago, nchuckle said:

In the very long run the quality and longevity of a proper Mitsubishi inverter unit will pay off best. That brand is regarded by professional fitters is one of the best. Had a few units in our house for around 9 years with little problem apart from servicing. So last year for another house went for the latest Mitsubishi inverter unit circa 25k. Whisper quiet and efficient and expect it to be there 10 years later. 

The only problem we have had with air-cons is the inverter type one. 

Our usual air-con cleaner and service guy won't touch our one we have a problem with he has gave us someone else who deals with and knows inverters and repairs. 

[Andycoops]

On 3/19/2021 at 3:48 PM, KannikaP said:

Just looked and it says non-install / does not include installation fee.

Where is the compressor please? And how much did it cost?  Only nine years to go on the warranty....do you think it will make it?

Try HomePro, they offer installation services, might even be free, if you ask.

[RocketDog]

22 minutes ago, Kwasaki said:

Well on reflection there not really air-cons as such there fan coolers and have there uses.

As I said we use it outside mostly now as well not so much inside and they are cooler that a fan.

Our combined household fridge/freezer it is big enough to hold blocks of ice that fit in the fans ice compartment.

You get a blue thing you can put in freezer but we use block ice that we form ourselves.

So you have the best solution for your needs and conditions. In engineering terms that's an elegant solution. 

Any way you look at it though you're paying to remove BTUs from some material and that costs money. The blue packs are typically phase change materials more effective than water at absorbing negative BTUs so to speak. Several smaller packs might be more effective than an ice block because of the greater surface area.

Adding some salt to your water before freezing will lower the freezing point of the ice making water a bit more effective too, especially since you can re-use the salt.

But you certainly can't very well cool the whole outdoors with an air-con, so for spot cooling you've got a good solution. 

You might look into misters for your outside area. They've gotten popular in USA and the few times I've seen them in action they've been effective and don't use much water. But to work you have to run your house pump for sufficient pressure. Sigh...... 

Ultimately there is no free lunch although solar-heated ammonia-based zero energy-consuming freezers come pretty close. I have an antique one that uses a 100watt heater element and in college had a huge and very heavy refrigerator powered by natural gas. Old technology now largely forgotten. 

Stay cool and pray for rain. ????

[tifino]

the 2 basic commion designs of portab;le 'aircon' each have their respective downfalls...

 

 1. the Swampy - loses efficiency more, the more humid the environment is i.e in the tropics it is a no go!

 2. the compressor based units:

 - If it is left to its own devides and Not connected to the outside; the heat reduction in the room is slightly negated by the hot air expelled by the unit itself back into the room

- if the units hotside air is expelled to the outside via its hot air expel tubes; there is the lateral thinking problem that the aircon unit is now slightly 'depressurising' the room itself... which means that hpot iar from outside theroom will be getting drawn back in (via gaps such as under doors etc) - therefore again reducing the overall cooling effort within the room 

[RocketDog]

8 minutes ago, Kwasaki said:

The only problem we have had with air-cons is the inverter type one. 

Our usual air-con cleaner and service guy won't touch our one we have a problem with he has gave us someone else who deals with and knows inverters and repairs. 

Inverters are appropriate for global regions where electrical supply voltages/frequencies vary over the course of a day. They take whatever AC line voltage/frequency is available, rectify it to DC and then 'invert' it (ideally without a transformer) back to 3phase AC appropriate for the fan and compressor motors (often BLDC) usually running at lower voltages. Some portable Honda generators use this principal to provide 60Hz AC regardless of engine RPM. An inverter can use DC power (even from batteries) to produce AC power at virtually any frequency or voltage desired. You see them in the small inverters for use in cars to power small AC devices from the car battery. 

Back in the day car radios used high voltage vacuum tubes and an electromechanical vibrator was used to 'chop' the 12VDC into a square wave AC voltage that then drove a transformer to boost the voltage and then rectify it to create the >150volts DC the tubes needed. So these were in essence just early forms of inverters. The concept itself is old. Solid state devices now make this conversion very efficient, approaching 90%.

AC motors don't function well under voltage sag or brown out conditions and can actually be damaged from overheating. 

As an electrical engineer who has designed inverters for years to power BLDC (brushless DC motors) I can tell you both the motors and the inverter itself are more efficient than a transformer with winding IR losses and core losses, both manifesting as wasted heat. This is why you see them increasingly popping up in aircon, refrigerators and other devices that use more than a few hundred watts. 

I suspect your aircon guy avoids them because he doesn't understand them, but I could be wrong.

That said, virtually any design or concept can be crippled or defeated by poor (cheap) implementation. I have no doubt that certain brands of inverter appliances are best avoided. Any of the name brands will be well engineered though. 

Personally I buy such appliances based on their use of inverters. They last longer and save hundreds of kilowatts over their lifespan. The day is coming when you can't buy things like aircons without inverters; they just make too much sense. 

[Yellowtail]

19 minutes ago, RocketDog said:

Inverters are appropriate for global regions where electrical supply voltages/frequencies vary over the course of a day. They take whatever AC line voltage/frequency is available, rectify it to DC and then 'invert' it (ideally without a transformer) back to 3phase AC appropriate for the fan and compressor motors (often BLDC) usually running at lower voltages. Some portable Honda generators use this principal to provide 60Hz AC regardless of engine RPM. An inverter can use DC power (even from batteries) to produce AC power at virtually any frequency or voltage desired. You see them in the small inverters for use in cars to power small AC devices from the car battery. 

Back in the day car radios used high voltage vacuum tubes and an electromechanical vibrator was used to 'chop' the 12VDC into a square wave AC voltage that then drove a transformer to boost the voltage and then rectify it to create the >150volts DC the tubes needed. So these were in essence just early forms of inverters. The concept itself is old. Solid state devices now make this conversion very efficient, approaching 90%.

AC motors don't function well under voltage sag or brown out conditions and can actually be damaged from overheating. 

As an electrical engineer who has designed inverters for years to power BLDC (brushless DC motors) I can tell you both the motors and the inverter itself are more efficient than a transformer with winding IR losses and core losses, both manifesting as wasted heat. This is why you see them increasingly popping up in aircon, refrigerators and other devices that use more than a few hundred watts. 

I suspect your aircon guy avoids them because he doesn't understand them, but I could be wrong.

That said, virtually any design or concept can be crippled or defeated by poor (cheap) implementation. I have no doubt that certain brands of inverter appliances are best avoided. Any of the name brands will be well engineered though. 

Personally I buy such appliances based on their use of inverters. They last longer and save hundreds of kilowatts over their lifespan. The day is coming when you can't buy things like aircons without inverters; they just make too much sense. 

I think people with MEA service generally do better with inverters than do people with PEA service.

I love my three new inverter AC units, but to be clear, if the units are sized correctly, the cost savings should not be that significant should it? 

[Chongalulu]

2 hours ago, Kwasaki said:

The only problem we have had with air-cons is the inverter type one. 

Our usual air-con cleaner and service guy won't touch our one we have a problem with he has gave us someone else who deals with and knows inverters and repairs. 

I think that may be more to do with the brand (not Mitsubishi?) and you guy is the equivalent of someone who won’t touch fuel injection because he only understands carburetors ? 

[DJ54]

Bought one of the more expensive portable air conditioner when waiting fir house to be completed. My opinion is a big 

waste of money. Gave it away. Bought a wall unit and once house was completed moved it to new place...

[Kwasaki]

2 hours ago, RocketDog said:

Inverters are appropriate for global regions where electrical supply voltages/frequencies vary over the course of a day. They take whatever AC line voltage/frequency is available, rectify it to DC and then 'invert' it (ideally without a transformer) back to 3phase AC appropriate for the fan and compressor motors (often BLDC) usually running at lower voltages. Some portable Honda generators use this principal to provide 60Hz AC regardless of engine RPM. An inverter can use DC power (even from batteries) to produce AC power at virtually any frequency or voltage desired. You see them in the small inverters for use in cars to power small AC devices from the car battery. 

Back in the day car radios used high voltage vacuum tubes and an electromechanical vibrator was used to 'chop' the 12VDC into a square wave AC voltage that then drove a transformer to boost the voltage and then rectify it to create the >150volts DC the tubes needed. So these were in essence just early forms of inverters. The concept itself is old. Solid state devices now make this conversion very efficient, approaching 90%.

AC motors don't function well under voltage sag or brown out conditions and can actually be damaged from overheating. 

As an electrical engineer who has designed inverters for years to power BLDC (brushless DC motors) I can tell you both the motors and the inverter itself are more efficient than a transformer with winding IR losses and core losses, both manifesting as wasted heat. This is why you see them increasingly popping up in aircon, refrigerators and other devices that use more than a few hundred watts. 

I suspect your aircon guy avoids them because he doesn't understand them, but I could be wrong.

That said, virtually any design or concept can be crippled or defeated by poor (cheap) implementation. I have no doubt that certain brands of inverter appliances are best avoided. Any of the name brands will be well engineered though. 

Personally I buy such appliances based on their use of inverters. They last longer and save hundreds of kilowatts over their lifespan. The day is coming when you can't buy things like aircons without inverters; they just make too much sense. 

I disagree, if you're home is not properly insulated and in addition the room in question is not sheltered from all day Sun heat an inverter air-con will cost you more in electricity than a normal available cold cooling type. 

 

And I refer to my post stated before, out of the 5 air-con units we have the only one I've had trouble with is the inverter one, so sorry for me the proof of the pudding is in the eating so to speak. 

 

If it's the case in the future that all you can buy are inverter type I hope they improve in there reliability.