Inverter AC for 120~145 Sq Ft Bedroom

@Crazy_Eddy - yes good discussion about the EER that it would be zero at start to high EER once it starts cooling correctly. The main thing rather than any thing else like EER etc I have found is that there has been no effect on my electric bills post installing the inverter. Thus for my requirements I found no good investing additional money on an inverter. Earlier the 3 Star AC was cooling the room as well and I thought that installing an inverter would save me money which it did not.

Any inverter AC manufacturer you see compares savings of inverter as against a regular 2 Star AC (which has the lowest COP). Hence, the savings look great on paper. But if you have a good 3 or 5 Star AC then I have calculated and found that on a 8 hour run of a AC the savings would not be more than a couple of units.
 
Any reason you want a picture? Then you will say you want the serial number, then open the outdoor unit and compressor number and so on. When I have given a specific model that I have it should suffice. FYI. It Reads Made in Thailand.[DOUBLEPOST=1399366415][/DOUBLEPOST]Why was my post removed? Any specific reason? Requesting a member to maintain decorum of the forum is good for the forum. I think forum should encourage that rather than deleting posts.
 
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Yeah but when a sales guy said Sharp uses MHI compressors, you were quick to embrace it
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He didnt say sharp uses MHI..
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I know he didn't say it - I just said he was quick to accept vvinashh's claim that it was an MHI, and added it to his review even though he was unable to see the compressor or verify it himself

Yes I believed what vvinashh had said. I do not think him to be a sales guy. He is also present in other forums and provide invaluable comments to many members.

Likewise I believe in you and Arjun as I have read your previous posts. We the forum members exist due to mutual trust & respect for each other.
 
^ I didn't say vvinashh is a sales guy; his source was a sales guy.
Mutual trust/respect for him went out the window after he threw a hissy fit and got defensive and accused me of posting false information! Anyone who's been on the forums long enough knows the age old rule - no pic no talk.

Any inverter AC manufacturer you see compares savings of inverter as against a regular 2 Star AC (which has the lowest COP).
Only Sharp is comparing Inverters vs 2 star ACs.
 
Yes but what is mentioned in their brochures about 20-30% savings compared to a regular AC. That is usually referred against 2 Star ACs, hence savings look huge on paper.
No. Their website comparing 2 star ACs and the Inverters claims a savings of 52%.

Can you perhaps find out from your dealers + technical sources how much power is lost as a heat pump reaches equilibrium so we can carry forward this discussion in a more meaningful manner?
 
No. Their website comparing 2 star ACs and the Inverters claims a savings of 52%.

Can you perhaps find out from your dealers + technical sources how much power is lost as a compressor in a heat pump reaches equilibrium so we can carry forward this discussion in a more meaningful manner?
Ok if you go to daikin website which shows payback period, between a 3 Star and Inverter they mention a payback of roughly 4 years if the AC is run for 8 hours a day for 8 months in a year! Now most members agree that for residence most houses will use it for around 4 months and your payback period simply doubles. These are actual manufacturer claimed figures under "ideal" conditions so even if we consider that, you find that inverter are not beneficial in many scenarios and are quite great with great payback if say its run through out the year for say 10-12 hours a day.
 
Ok if you go to daikin website
Link please.

Also you haven't answered my earlier query on sizing a non-inverter AC for a single room :)
This is very true, but this also explains why an inverter AC is useful. The way to size an AC is to calculate the heatload. But its impossible for the heatload to stay consistent for any room. The heatload doubles just by a doubling in temperature difference between the inside and outside temps. Lets say your inside temp is set at 27C and ambient is 30C (3C temp difference), and your heatload calculations say a 1T AC is appropriate. Now lets say the ambient temp rises to 33C (6C temperature difference), your heatload calculations will also double and you would need a 2T AC. You will have to size the AC to the maximum requirement so that it functions under all conditions. So how do you size *one* AC when the heatload requirements vary so much with just changing ambient temperatures?
 
Link please.

Also you haven't answered my earlier query on sizing a non-inverter AC for a single room :)
its daikinindia / com.

Sizing of an AC would be based on individual requirements. You need to calculate the BTU required for a room and only then start selecting the AC. Irrespective of the type of AC you choose, BTU calculation is a must and sizing should be done accordingly. You rightly point out that there is no optimum heat load count possible, but usually you average out based on your requirement and take an average figure. Say if your room BTU suggest a 1 T AC then based on variations you might choose a 1.25 or 1.5T AC. Also like you point out, inverter has various options from low to high so it should be quite suitable for various climates. It should really provide optimum cooling in all ranges, but like I said in my case that has not been so. I have found consuming almost similar or more than my old 3 Star AC.
 
^ Yes daikinindia.com has many pages, hence I requested for the link to the specific page :)

Say if your room BTU suggest a 1 T AC then based on variations you might choose a 1.25 or 1.5T AC.
So you're saying a BTU calculation can vary by 50% - in other words you admit heat load calculations are hugely inaccurate? If you choose a higher capacity AC to account for the max variation, won't you have many on-off cycles when the heat load is lower? How do you propose optimally sizing the AC for a 50% variation?
 
^ Yes daikinindia.com has many pages, hence I requested for the link to the specific page :)


So you're saying a BTU calculation can vary by 50% - in other words you admit heat load calculations are hugely inaccurate? If you choose a higher capacity AC to account for the max variation, won't you have many on-off cycles when the heat load is lower? How do you propose optimally sizing the AC for a 50% variation?
www.msphptest.com.php5-14.ord1-1.websitetestlink.com / daikin2012 / DaikinWeb /
The link is really accessible from their front page. If you see the slider first thing that comes up is the Inverter / Non Inverter comparison

Yes the BTU conversation is open to discussion and variations. Same as inverter technology is. Some get just 100 Rs bill by using for 8 hours a day per month, while when I use for 4 hours a day my bills are 10 times that. So some have supposedly benefited from inverters but in my case I am paying almost the same bills as my old 3 Star with just 2.7 COP.

But you can more of less count the appx heat load based on what kind of indoor temperature you have. Say if your indoor temperature is at 35 it will usually be around that level most of the times. Now to bring temperature to 25 that is a 10 degree difference, you need to calculate for that room how much BTU is needed.
 
Ok if you go to daikin website which shows payback period, between a 3 Star and Inverter they mention a payback of roughly 4 years if the AC is run for 8 hours a day for 8 months in a year!
I don't know what you did, but here's what the daikin calculator said when comparing an inverter and a 2014 5 star. 7k vs 11k is a ~37% savings :-

The payback period is not "manufacturer claimed" as you said - the prices are all user inputs. I can guess what prices you put ;)

Some get just 100 Rs bill by using for 8 hours a day per month, while when I use for 4 hours a day my bills are 10 times that. So some have supposedly benefited from inverters but in my case I am paying almost the same bills as my old 3 Star with just 2.7 COP.
The big question - If your bills are 1000 rs a month, how were you expecting to recover your additional costs with 30% savings i.e. 300 rs a month?!

But you can more of less count the appx heat load based on what kind of indoor temperature you have. Say if your indoor temperature is at 35 it will usually be around that level most of the times. Now to bring temperature to 25 that is a 10 degree difference, you need to calculate for that room how much BTU is needed.
Which city has an ambient temperature consistently at 35C - night or day?
 
Fascinating discussion & thanks for all the replies

So what i infer from the above is, i'm better off buying the 3 Star a/c instead of the Inverter considering my limited planned usage¿

I'll be heading over to the local electronics showrooms tommorow afternoon for a final round-up & eventual purchase. Anything i need to ask the salesperson/keep in mind/check ?
 
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I don't know what you did, but here's what the daikin calculator said when comparing an inverter and a 2014 5 star. 7k vs 11k is a ~37% savings :-
If you read carefully I have clearly stated I had compared a 3 Star AC to Daikin Inverter. Here is the screen if you feel I am lying.
voltas_daikin.jpg


The payback period is not "manufacturer claimed" as you said - the prices are all user inputs. I can guess what prices you put ;)
Yes I have input prices that I found online for the products. That too the lowest prices I could find online for each of them.

The big question - If your bills are 1000 rs a month, how were you expecting to recover your additional costs with 30% savings i.e. 300 rs a month?!

Why do members always keep guessing others bills? What I said is that it is hard to believe someones bills can be just 100 Rs running the AC for 8 hours a day. My bill from ONE AC is much more than that and even though used for around 3 hours a day.

Which city has an ambient temperature consistently at 35C - night or day?
Any house inside temperature is usually around 35. It may be plus / minus a couple of points but usually the inside temperature has been found around that range. Also the AC has to cool the inner temperature, so based on that all calculations are to be made and not based on outside temperatures.
 
If you read carefully I have clearly stated I had compared a 3 Star AC to Daikin Inverter. Here is the screen if you feel I am lying.
Why don't you compare a Voltas 3 star to a Voltas inverter?
You may not be lying, but you cleverly hid the fact that you were comparing ACs of different price segments with a whopping 21k price difference!

Why do members always keep guessing others bills? What I said is that it is hard to believe someones bills can be just 100 Rs running the AC for 8 hours a day. My bill from ONE AC is much more than that and even though used for around 3 hours a day.
Yes why do members keep guessing other people's bills and say that people with Inverters are getting 100 Rs. bills? If some joker told you that and you bought your AC actually expecting 100 Rs bills, then who is the real joker?
BTW you clearly said your bills were 10 times that i.e. 100 x 10 = 1000 Rs.

Also the AC has to cool the inner temperature, so based on that all calculations are to be made and not based on outside temperatures.
Why are you debating inverters when you have no idea how a basic AC works. Where do you think the heat is being dumped - Inside or outside? Do you know your refrigerant is cooled in the outdoor unit? Is it easier for this refrigerant to cool if the outside air is hot or cold? Take some time off to figure out these basic concepts, then maybe you can make some sensible posts.
 
Why don't you compare a Voltas 3 star to a Voltas inverter?
You may not be lying, but you cleverly hid the fact that you were comparing ACs of different price segments with a whopping 21k price difference!
There is no such restriction on what I need to choose. Daikin Site offers various brands and Voltas is a leading brand so I chose that. I did not compare it to any unbranded AC, so if a good brand is available at X price why would I choose something else? And its a fact that if you do real calculations most of the time the payback period is so long, its not worth considering inverter ACs just for power savings.

Yes why do members keep guessing other people's bills and say that people with Inverters are getting 100 Rs. bills? If some joker told you that and you bought your AC actually expecting 100 Rs bills, then who is the real joker?
BTW you clearly said your bills were 10 times that i.e. 100 x 10 = 1000 Rs.
Please mind your language on this. I had mentioned that its impossible for someone to get a bill of Rs. 100 if its used for 12/24 hours as this forum is flooded with posts in this regard. Either forum moderators need to ask proof or delete it because the members are shouting over the roof that this is possible even though technically its not possible, but there might be some unassuming members who will feel that really inverters are saving so much money.

Why are you debating inverters when you have no idea how a basic AC works. Where do you think the heat is being dumped - Inside or outside? Do you know your refrigerant is cooled in the outdoor unit? Is it easier for this refrigerant to cool if the outside air is hot or cold? Take some time off to figure out these basic concepts, then maybe you can make some sensible posts.
Ok I have no basic knowledge of how ACs work. So will not post further on this forum. Have had enough of members trying to reject what others say and just to prove that what they say is right and what others think is completely wrong. I thought this forum was more to do with members helping each other find the perfect solution for their AC requirements, but here I find most of the members are busy promoting Sharp ACs and trying to prove only that is the best and there are no other ACs in the market that can meet their standards. Here some members have tried hard to discuss with figures how only in some scenarios inverters are good, but in most cases it does not result in a power savings.

I have had some great time on this forum, but have decided to call it quits as there is too much name calling going on and trying to prove only they are right. Please disable my account with immediate effect. Thanks
 
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