[D4d-maniac]

Originally Posted by Aroy

Could you share the model numbers and costs. 48HP is around 10T, and I am looking for 8T-10T solution.

The model number is Diakin VRV 4. It uses R410A refrigerant. The cost is approximately 50k per hp excluding the ventilation and central control panel.

There is some discrepancy in the conversion units. According to these guys 1.2 hp equals 1 ton of refrigeration. As the tonnage required for my setup was 54.3Tr it comes out to 45 hp. Attaching the details of equipment installed.
I might be wrong at some conversion of units as I am not an engineer, although I tried to understand all of this as best as I could.

[drpullockaran]

Originally Posted by civic-sense

Godrej has an aluminium condenser and R290 refrigerant.

My father has this in his bedroom and Mitsubishi in the other bedroom. The Godrej is dead in 3 years due to corrosion of the aluminium tubing of the outside unit. Dad spent a bit on the Godrej and got the condenser changed to copper.The Mitsu with copper is perfectly fine. We stay in Ernakulam, Kerala which is 9 km from the sea.

[rm_arjuna]

our lg 1.5 ton is around 10 yrs old with an aftermarket hitachi compressor changed 2 yrs ago after the original unit went kaput. Since last week the cooling efficiency has reduced. Have noticed excessive water droplets on the copper pipes on the outdoor unit. Is this because of lack of insulation foam or drop in refrigerant gas. Attaching some pictures

[civic-sense]

Originally Posted by anupmathur

LOL, quite some mistake!
You've used the 'KWHrs per year' (annual energy consumption) figure of the inverter AC and compared it to the 'Wattage' rating of the three star AC!!
No wonder I found the numbers hard to believe.

Yeh, that is an unpardonable error. Looks like Daikin has left out the annual consumption from the PDF. Incidentally they have not provided the values for any 3 star regular ACs. So it is not possible for me to compare.

However I looked at some Bluestar models (https://www.bluestarindia.com/roomac...c-brochure.pdf). Their annual consumption ranges from 1273 to 1285 units.

So the new math is:

Electricity cost per unit - Rs 7.5

Daikin 5 star inverter - 744 units per year = 62 units per month = Rs 465 per month
Bluestar 3 star regular - 1273 units per year = 106 units per month = Rs 795 per month

Savings Rs. 330 per month.

Much lower than my initial calculation, but still pinches IMO.

[anupmathur]

Originally Posted by civic-sense

...
....
Much lower than my initial calculation, but still pinches IMO.

I agree every little bit counts. My suspicion has been that well before any energy saving benefit can be realized something or other will break and need replacement and will not be part of the guarantee!

And don't we see right here that that is happening in many cases!

[chiragpatnaik]

Originally Posted by anupmathur

I agree every little bit counts. My suspicion has been that well before any energy saving benefit can be realized something or other will break and need replacement and will not be part of the guarantee!

And don't we see right here that that is happening in many cases!

Inverters are useful if you use them 8-10 hours daily and 20 on the weekend for about 6-8 months (yup Delhi weather). Else 3 star will suffice. There's a case to go for a R410 as the older gas may not be available after 2022.

I bought 4 Voltas ACs last year (5 year warranty on each). Mostly happy with all of them. Especially the inverter which has done duty at 46-47 and chilled us sufficiently.

[sandeepmohan]

Originally Posted by rm_arjuna

Is this because of lack of insulation foam or drop in refrigerant gas. Attaching some pictures

If refrigerant is low, you'd see frosting as well. Does the air throw feel as cold as it usually does?

When was the last time you cleaned the air filter?

[Thad E Ginathom]

Originally Posted by rm_arjuna

Have noticed excessive water droplets on the copper pipes on the outdoor unit. Is this because of lack of insulation foam or drop in refrigerant gas. Attaching some pictures

Is it really a new thing? If the pipes are cold, then water from the atmosphere will condense on them.

Look at the indoor unit. Look for ice on the cooling coil. It may indicate low gas or a gas leak. Also check that the indoor-unit fan is clean. Even a small amount of grunge buildup on it seems to spoil its aerodynamics, and airflow is reduced. Sometimes that can cause cooling-coil ice.

[fine69]

What could possibly be the issue when a window AC throws chilled air but the fan speed has reduced significantly. I called up the Hitachi technician, he did a wet service claiming that a dirty condenser would've been blocking the air flow.

Is it a sign of motor going bad? I would rather get it changed than spend a sleepless night in case the motor goes kaput.

EDIT: Could it have anything to do with the stabilizer? I have a VGuard stabilizer but it doesn't have any display.

[Aroy]

Originally Posted by fine69

What could possibly be the issue when a window AC throws chilled air but the fan speed has reduced significantly. I called up the Hitachi technician, he did a wet service claiming that a dirty condenser would've been blocking the air flow.

Is it a sign of motor going bad? I would rather get it changed than spend a sleepless night in case the motor goes kaput.

EDIT: Could it have anything to do with the stabilizer? I have a VGuard stabilizer but it doesn't have any display.

Get the AC wet services ASAP. Insist that they open up the top cover and thoroughly wash the condensers till they are bright and shining.

I have 3 Hitachi, and all of them are sensitive to clogged condensers. Initially the fans start slowing down and ultimately they blow. Replaced fans 3 times in 2 AC's before I got to know this. This is primarily due to extremely fine spacing of fins in the condenser. Fine spacing increases thermal efficiency at the cost of fouling/jamming the fins if the location is a bit dusty.

Now a days I get one AC (which is prone to condenser jam) wet serviced after two months of running - 3 to 4 times a year. The amount of muck that comes out each time is to be seen to be believed.

[fine69]

Originally Posted by Aroy

Get the AC wet services ASAP. Insist that they open up the top cover and thoroughly wash the condensers till they are bright and shining.

This time they came with a chemical to clean the condensers and the condenser is shining like new. The fan speed was still an issue, they've now replaced the capacitor as I write this. If this also doesn't work then he's suggesting a motor change, cost around 5500/-.

[Aroy]

Originally Posted by fine69

This time they came with a chemical to clean the condensers and the condenser is shining like new. The fan speed was still an issue, they've now replaced the capacitor as I write this. If this also doesn't work then he's suggesting a motor change, cost around 5500/-.

I guess from the price that it is a DC motor in their 5* AC. If so then I would suggest that you get rid of the AC as fast as possible.

I had the same problem and the motor blew two years ago. This year the motor has started slowing down, so I guess the motor is again on its way out. The motor is a Chinese product and pretty bad, but there is no substitute for it and it is not available in the Market (unlike normal AC motors which you can rewind/get new for between 500 and 2K), so you are stuck with Hitachi. So if your AC is nearing 5 years of age, sell it. I usually get between 4K and 6K for my old AC's which are usually in running condition.

[ravivarmav]

I'm using a 1.5 ton, Hitachi 5* and Daikin 3* AC's in my Master and Child bedrooms. Both has good compressors.
Here are few Pro's and Con's of both the AC's I observed
Hitachi:
Pro's:
Technically advanced
Less power consuming with good cooling efficiency
Easy to clean filters

Con's:
Very bad customer service.
Not so quite.
Little Expensive compared to Daikin.

Daikin:
Pro's:
Very very quite. Absolutely zero noise.
Good cooling efficiency
Good customer service
Slightly less expensive compared to Hitachi

Con's:
Technically not so many options, but still good with all basic features.
3* Model doesn't have a LED display on AC.
Remote doesn't have backlit display(not sure of high end 5* models) and difficult to operate at nights.

Overall, considering the pricing and performance.. I vote for Daikin. If you are okay spend few more bucks(around 2-3k more for same tonnage), you can go for Hitachi.

Pricing:
Hitachi RAU518AVD (5*, 1.5 ton, copper) will cost around 42k.
Daikin FTC50QRV16 (3*, 1.5 ton, copper) costed me 36k from a dealer in Hyderabad.

[Thad E Ginathom]

Our Sharp saga is still rumbling on.

I think I posted that we got some customer service people who said that indeed the main board had to be replaced, 8k, which we thought was worth it.

Then our local guy got involved again, saying that he had found a scrapped machine, chucked out because someone screwed up a cooling-coil repair beyond fixing. He got the "board" (quite a large unit) and swapped it in.

But the machine started, started cooling, and then stopped cooling. So he swapped out some of the inside unit circuitry too. And it still doesn't work.

Poor guy never wanted to touch this machine at all, but doesn't like failure!

So he is still going to try and build one working machine from our 's and the scrap machine.

He's good... But not fast due to demand. So there are days in between each attempt when other stuff gets done.

Now that dog days are over, I'm just about ok and not in a suffering hurry. In July I get more income... If nothing fixed by then I'll just go out and buy the new machine I'm hankering after anyway.

[fine69]

Originally Posted by Aroy

So if your AC is nearing 5 years of age, sell it. I usually get between 4K and 6K for my old AC's which are usually in running condition.

The AC will complete 5 years in a few months. Today morning after he replaced the capacitor the AC continued at a very low fan speed, only to die down in another half an hour.

I've logged a breakdown ticket with Hitachi and for now I have no option but to change the motor.

However, is spending 5-6k every 5 years too bad for a window AC? I'll be shifting to my new house in another 2-3 months and I wasn't sure whether to keep it in the 3rd room as a backup or get rid of it altogether and get all Daikin Splits in every room.