Need suggestions for purchasing a new AirCon.

Unfortunately, most of the people don't know about it, being such an important part of the installation process. The connecting pipes between IDU and ODU has air which has impurities. These impurities, if not removed, will form a grease like paste or something which reduces the cooling capacity of the machine and increases chances of corrosion/rusting from inside(chemically) due to compression/expansion of the refrigerant. Hence it is important to remove all the impurities before using the machine for the first time or refilling gas due to leakage.
The ac's will work whether you vacuum it or not. But with time, its cooling capacity reduces due to above mentioned process and more so in your case since you use it 24*7. It leads to increase in maintainance cost, higher electricity bills.
What service guys do is use the existing gas to purge the impurities present in the system. While this works good and get the job done, it does so at the cost of the refrigerant which leads to less cooling.
Due to dirt need to wash them so the rust/corrosion can't be helped
Think of the coating/layer as a raincoat. The raincoat will prevent the extent your ac comes in contact with moisture increasing life and maintaining cooling capacity than with exposure to moisture when pipes are naked. Point is if you have coating you can increase the life of your unit. My previous ac unit died within 10 years as it was under direct attack from moisture and my pipes were naked.
When they take the AC out to properly wash it with a hose the amount of dirt that comes out of it is staggering.
It's not surprising. Running Ac continuously will attract dust and will build up over time due to static electricity. This cannot be helped.
 
Will keep this in mind for next time. Is there a point to getting it done on older ACs? I mean the ones I am already using. I don't know if the coating is there or not on my ACs as usually I am not around when the service people are doing it. Does the coating help with a lot of water? The washing done on the AC uses a lot of water to clean it so I was wondering if this coating will help or not when exposed to a lot of water. All the ACs I have had usually are at least somewhat rusted in 2-3 years. I do wish something could be done about the dirt/dust. The continuous use along with dust/dirt causes the AC to loose some of it's cooling capacity.
 
Given your ac usage, I would say not worth it.
Coating has no relationship with the amount of water used. In layman's term, it forms a barrier between water drops/moisture in air and the ac pipes. So water won't easily rust the pipes like it would when there is no barrier. Do note, eventually this barrier will give up with time and water will start rusting once it has access. It all depends on the coating quality.
Rusted in 2-3 yrs... Seems like naked pipe to me, Similar to my first ac.
If your pipes have rusting, corrosion then there is a good chance of refrigerant leaking from ac and reducing cooling.
What I mentioned above applies to both IDU and ODU.
Btw, which part of India are you from?
 
I see, so then would it not mean that by using a lot of water the coating will erode quicker, particularly from the water pressure due to the hose? I only saw the bottom part of the window AC to be rusted, not the pipe. When I say rusted I mean any part of the AC, internal or external. Usually I do not see the internals, nor do I pay attention to them as generally after a good washing the AC goes back to cooling the way it was before. Over time this diminishes leading me to replace it. This effect is rather random and sudden when it stops cooling, most times it resumes cooling after the wash. I am from Kolkata, I live near some busy roads in the city so there is always dust/dirt on a normal day. Where are you from?
 
No, it won't. It's like a permanent paint. When you paint your house, it starts fading slowly only after a long time. Also, the exposure to water from hose is for a limited time like 1-2 hours and that too not everyday. Can you share some pics of your window AC to get a better idea? Washing is a good way to rid of all the dirt, dust.
Frankly, any ac, with or without protection, should last you atleast a decade under normal circumstances. Problem of rusting, corrosion comes in when your AC is regularly in contact with moisture(like everyday due to high humidity or living near sea side or having a drainage nearby to expose it to chemical gases causing corrosion).
Do yoju happen to live near sea or drainage? How often do you clean you ac with water?
I am from Mumbai and I face the double problem of rusting and corrosion.
This is how a coating/paint job is done, just to give you an idea.
 
https://www.hitachiaircon.in/ranges/window-acs/kaze-ac-series This is the AC I have in my room where the AC runs 24x7, the 2 ton variant. Maybe for other people the AC lasts a decade, with my use after 2-3 years the cooling is lowered and the AC is worn out. If most people use the AC 6-8 hours a day then my usage is triple that, so in 3 years it would have been running for 9 years in terms of someone who uses it for 8 hours a day for the whole year. Not to mention the continuous load it is under without rest which may cause extra heat in the AC. I do not live near the sea, there are regular drains. The AC is cleaned about 10-12 times a year. To note, other rooms in my house which don't see so much use have lasted a decade, one room which sees about 8 hours a day of usage is about 11 years old. While that particular unit is functional I find that it has limited cooling.
 
Running 24*7 could be a reason for early breakdown in actual functioning.
Regardless, next time when going for a new ac do keep the above mentioned features in mind. They will surely help to increase longetivity by a certain number of years.
 
Will keep it in mind but as you said the vacumming is not worth it for my use. As for rusting/corrosion, I doubt it is the reason why the AC is cooling less, it's mostly body damage that I have observed. Will need to replace the AC every few years anyway. The next time I will probably go with Hitachi/Mitsubishi, if I come across one with coating that is also 2 ton then I might get that.
 
as you said the vacumming is not worth it for my use
It will not be useful for all your existing ac's as they are already operational. Vacuuming is the process done during installation of ac before it becomes operational. Will surely help to increase its life.
If high cooling is your requirement, then go for Mitsubishi Heavy Industries. Nothing beats it's performance. But do inquire in your area regarding availability and service. MHI have very less dealers, and few service centres.
 
I have a Mitsubishi window AC and it's a little old and does not cool as well as it used to, last time I went to buy an AC the Mitsubishi 2 ton was not available so bought Hitachi instead. It was good in the beginning though.
 
You don't or can't do the vaccuming of the refrigerant pipes in a windows AC as everything is already pre-assembled. That is only needed for split ACs where connection needs to be done for ODU and IDU.
For 24x7 operation you would be better off with using an appropriately sized inverter AC as they are designed for such type of usage. Also, instead of buying a new AC every 2-3 years, you should just get it's compressor replaced by a competent guy. It costs a lot less to just replace the compressor and other components are usually fine. Also, when you are cleaning the outdoor coil with water, make sure that the fins don't bend and it is advisable to not use a high pressure washer. Bent fins are also a reason for cooling performance to drop.
 
You don't or can't do the vaccuming of the refrigerant pipes in a windows AC as everything is already pre-assembled. That is only needed for split ACs where connection needs to be done for ODU and IDU.
For 24x7 operation you would be better off with using an appropriately sized inverter AC as they are designed for such type of usage. Also, instead of buying a new AC every 2-3 years, you should just get it's compressor replaced by a competent guy. It costs a lot less to just replace the compressor and other components are usually fine. Also, when you are cleaning the outdoor coil with water, make sure that the fins don't bend and it is advisable to not use a high pressure washer. Bent fins are also a reason for cooling performance to drop.

I have 3 inverter ACs as I mentioned (all split) and they can't compare to the regular ACs. IMO the "local" or "o general" (copies?) ACs we used to get some 20-30 years ago had much better cooling, even if they used more electricity. If someone told you that inverter split ACs are good with 24x7 usage they would be wrong, at least the split ones can't do that well. The last time the old AC developed major problems, I was quoted 10,000 INR to fix it, a new AC is about 30-35,000 INR last I checked, to me it was a better choice to get a new AC.
 
For most people, an inverter AC is better for 24x7 running as, instead from switching on and off, they ramp up and down their power depending upon the room temperature.
Since your requirements are very different especially the temp range that you operate at (17-22),maybe in your case a normal AC works better. Most people I know keep temp in 25-28 range and in that range, a normal AC switches on and off quite frequently and hence an inverter AC is better suited than a normal AC especially if running long hours. Till I was in Chandigarh, even my AC used to run 24x7 at 25°C, for 7-8 months and I was happy with my normal AC for the 3 years I used it but I did oversize it a bit with 1.5T for a 12x12 room which got sun from 3 sides. We also had a Hitachi 1.5T windows ac for over a decade in the other room and it also performed satisfactorily at 23°C.
But if I were to buy today, I would buy an inverter AC for long hour usage as that is what they are designed for.
 
I understand what your saying and how inverter ACs work, they don't always operate at full power and that is something I do not want, I want the AC to operate at full power. This will provide maximum cooling. Theoretically you might say that an inverter AC might operate at full power initially and once the room is cool it can lower its cooling capcity however in practical use I don't see any such occurrence, by that I mean that I find the cooling lacking. The inverters are touted to save electricity, rather than operate 24x7 from what I could see on their websites and talking to various dealers and ac service people. Next time I could try an inverter window AC but I doubt it will make any difference. My usual temps in the summer are 17-19C, 22C only when I have a cold or fever. My AC runs 24x7, 12 months a year. Every year until it is replaced. The only time it is not working is when it is being serviced. For me operating at 24C or higher is basically the same as AC being off, there is no point to it for me.
 
I understand what your saying and how inverter ACs work, they don't always operate at full power and that is something I do not want, I want the AC to operate at full power. This will provide maximum cooling. Theoretically you might say that an inverter AC might operate at full power initially and once the room is cool it can lower its cooling capcity however in practical use I don't see any such occurrence, by that I mean that I find the cooling lacking. The inverters are touted to save electricity, rather than operate 24x7 from what I could see on their websites and talking to various dealers and ac service people. Next time I could try an inverter window AC but I doubt it will make any difference. My usual temps in the summer are 17-19C, 22C only when I have a cold or fever. My AC runs 24x7, 12 months a year. Every year until it is replaced. The only time it is not working is when it is being serviced. For me operating at 24C or higher is basically the same as AC being off, there is no point to it for me.
Mind telling in which city do you reside that needs 24x7 cooling, is it a coastal area with very high humidity?

Imo anything below 22C is uncomfortable and not healthy for an average individual. Air needs to be exchanged at least once in 24 hours or else your AC will keep on circulating the stale air.
 
Ahh, okay I guessed so because anytime I feel that uncomfortable is during the peak monsoon period ie. August. Feels like a pressure cooker, 24x7 AC is a must in that period.
 
I use my air conditioner at 26C in Mumbai. It's comfortable for enough for me. It is too chilly if I go below it. Do you guys recommend a separate dehumidifier?
 
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Isn't Mumbai's weather already humid for humidifier?
Unless your skin feels itchy due to dryness or dry cough due to soreness in throat, don't think there is any need.
If you have a medical condition then it's a different story.
Or did you mean to say dehumidifier??
 
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