[Thad E Ginathom]

Originally Posted by Guite

Thanks for the input. One problem is that IDUs are not sold separately by reputed brands, so the only choice is local brands. The feature set and performance characteristics will be governed by the IDU, judging by your response above. That's a bummer!

It is either a bummer or a way of getting working AC without spending on a brand new unit --- depending on which way one looks at it.

Actually, a year ago, our local-street engineer suggested that he could replace the IDU of our main-hall Samsung, rather than mend the leaks. I had planned to only get another year of use out of it, so did not follow up, but now plans to replace it with something expensive are shelved. Even a local-street reconditioned unit might be of interest.

[AWD]

Originally Posted by Aroy

R32 is the latest and is supplanting R410A, but it is flammable.

Flammable is danger but since split units are placed outsides, it should be safe for users.

Originally Posted by optimist

The data is of the higher end models where aluminum is not used.

Okay, but the fins are of various types in the higher models too I guess.

[anupmathur]

Originally Posted by AWD

Flammable is danger but since split units are placed outsides, it should be safe for users.



Okay, but the fins are of various types in the higher models too I guess.

The first part first: The same refrigerant flows in EXACTLY the same quantity in the IDU as in the ODU!

About fins: Indeed, there are high end models that too use aluminium fins!

[Lobogris]

Is it possible (and advisable) to switch outdoor split ac units (ones housing the compressor) with a different brand? I have a one ton Koryo split in a very large room while there is a 1.5 ton Samsung split unit installed in a tiny room. Would it be alright of we simply took the Samsung outdoor 1.5 ton unit and connected it to the Koryo inside unit (air handler) pipes and vice versa? The ac techs claim it would be fine but I am worried that there might be some weird issue due to incompatibility. It seems like the circuitry is all contained in the inside unit and all it does is issue a command for the outside compressor to switch on and off as needed. Is there something I am missing here?

[Aroy]

Actually there is no problem with Aluminum fins. The problem is in pipes. Copper pipes are easily repaired by braising and more malleable than Aluminum, hence crack much less.

Another problem with Aluminum is that it flows under pressure (that is why you will experience constant contact problems with older aluminum wiring), hence the joints/terminals are complicated to design (they have to maintain comtact and prevent aluminum from flowing). So a marginally indifferent manufacturing can be a potential problem with aluminum piping, not so with copper.

[anupmathur]

Originally Posted by Lobogris

Is it possible (and advisable) to switch outdoor split ac units (ones housing the compressor) with a different brand? I have a one ton Koryo split in a very large room while there is a 1.5 ton Samsung split unit installed in a tiny room. Would it be alright of we simply took the Samsung outdoor 1.5 ton unit and connected it to the Koryo inside unit (air handler) pipes and vice versa? ....

You will not achieve enhanced performance by coupling a 1.5 ton ODU to a 1 ton IDU. The cooling will barely improve.
Vice versa, ie 1 ton ODU with a 1.5 ton IDU will work to again provide only 1 ton worth of cooling.
In short, this is not worth doing.

[Lobogris]

Originally Posted by anupmathur

You will not achieve enhanced performance by coupling a 1.5 ton ODU to a 1 ton IDU. The cooling will barely improve.
Vice versa, ie 1 ton ODU with a 1.5 ton IDU will work to again provide only 1 ton worth of cooling.
In short, this is not worth doing.

Thank you for the advice. I will leave them as they are or change the IDUs over as well.
Could you please explain the reasons a bit? Would it be due to the smaller size of the coils in the IDU?

[anupmathur]

Originally Posted by Lobogris

.... Would it be due to the smaller size of the coils in the IDU?

Yes, indeed. That's for the 1.5 ton ODU coupled to the 1 ton IDU.
In the second case it is the smaller compressor and condenser in the ODU that will be unable to feed enough refrigerant to the 1.5 ton IDU.

[lancerlover]

Originally Posted by Lobogris

Thank you for the advice. I will leave them as they are or change the IDUs over as well.
Could you please explain the reasons a bit? Would it be due to the smaller size of the coils in the IDU?

Hi Lobogris,

Yes, the evaporator coil is one of the reasons why this would not have worked, coils like most of the other components in an AC are designed to handle a specific amount of load/refrigerant (within permissible tolerance) .

Since you have the connecting pipes etc already in place in both the rooms why don't you simply swap the complete units? this should be a easy job for any competent installer.

Also, shifting them doesn't mean that you have to refill the gas, saving the refrigerant in the ODU while dismantling is a very simple & common process and most installers do that (but they will still charge you for the gas if you are unaware), just let the guy know that you know about the process & won't pay extra for the gas.

[lancerlover]

Hi guys,

Last year around this time, I was in the market for 7 x 1.5 Ton split machines for my new home and I understand how stressful & demanding these purchases can be.

Would like to share a few points:

1-Buy your own installation kit, the going market rate for the standard quality stuff these installation guys carry is (across the brands):
-copper pipes Rs 350 per meter (both with cover)
-wall/floor stand Rs 250/- including all the nuts, bolts & washer.
-threaded drain pipe 25 per meter.
-ISI marked 3 core 2.5mm cable 45 per meter.

2- Insist on vacuuming the lines, do not get a split installed without vacuuming the lines first.If possible get it done in front of you & see to it that they run the pump for at least 20-25 minutes.

3-More than the brand name focus on the kind of service they offer in your locality- the voltas, bluestars, lloyds and the likes are all made by 3rd parties in China, what differentiates them (other than the company logo) is the kind of installation & service you get locally.

4-Do not blindly go for Inverter ACs, Yes, they do save money and energy but only when they are appropriately installed (capacity wise & usage wise) in a well sealed room otherwise they just go about functioning like a very expensive normal air conditioner. Also, going by the failure rate in my circle, I just couldn't convince myself to buy one over a 5 star ac.

5- Do not trust the dealers, these guys will say anything to make a sale & will push for the item with the most margin.Get them to unpack the ODUs- see, feel & compare the the build quality, open the cover of the IDUs at display, you will need to do that every week at home to clean the filters.This step alone helped me remove voltas & the likes and surprisingly sharp too from my list because of the flimsy build quality.

6-Last but not the least, If you are not in a hurry, buying online is one of the better options:
- Usually cheaper by at least a couple of grands.
- No surcharge on Credit cards.
- Free delivery.
- Unless specifically mentioned by the brand, there are absolutely no issues with installation or support for the ACs bough online.

At present, the only 2 etailers I trust & recommend for the big ticket purchase are Flipkart (WS retail) & Amazon (cloudtail).

I had to let go of a General, Napolean, LG, Onida & a Hitachi 1.5t window unit to make way for a couple of 3 star Panasonics and three 5 star LG splits & have retained a Hitachi & Blue star (splits) from the old lot for my office.

In between, before the LGs a few (4) Daikins (FTKP16PRV?) were ordered but never got them delivered because of the exorbitantly high installation cost quoted by their local service partner and partly because of the fear of high maintenance cost in the future.

Hope this helps.

[Aroy]

Originally Posted by lancerlover

Hi guys,

Last year around this time, I was in the market for 7 x 1.5 Ton split machines for my new home and I understand how stressful & demanding these purchases can be.

Would like to share a few points:
.......

Hope this helps.

How many of the 7 1.5T units will be operating at a time?
. If more than 3, then you should think of a large VRF unit. That unit can be configured for 3 to 5 tons, depending on the peak demand.
. If you plan to use two or more in the living room, then a 3-phase 3 to 4 ton unit will be more efficient

Now coming to installers.
In general most of the companies will refuse warranty claims if their installer is not involved. In case you want to carry out installations your self, there are a few options and then there is no warranty. You can visit a few large dealers of LG and Daikin in Lajpat Nagar and negotiate the installation of 7 AC, as well as AMC.

On the whole I have found that high end AC installers are rare, and when found quite expensive. When I got my Daikin installed I was impressed by the workmanship, but then they charged for every thing. Here is a break up of materials and
. Gas Pipes - go for Malaysian rather than Chinese pipes. Daikin requires larger diameter and wall thickness compared to LG.
. Water Pipes - go for rigid pipes of at least 25mm dia, rather than flexible or electrical conduit pipes
. Electrical cable - use 3 or 4mm single core electrical cables and run them through a flexible conduit, rather than buying 3 core cable. Some Daikin models require 4 cores.
. Installation, this is usually in the range of 1500 to 2000 per AC, but you can negotiate a bulk deal.


Costs. Here you are juggling between Capital cost and running cost. VRF units are generally more robust and last longer, while 2-3 star splits are very cheap to buy but expensive to run.
A 2-3 star 1.5T Split can be negotiated for around 30K + installation ~ 2.5L
An Inverter will be 50K - 3.5L
A VRF unit of 4T with 7 IDU will be over 4L more like 5L

For larger cooling load, I prefer larger VRF units as they have a low life time cost (and they last a lot longer). If you go in for a large single VRF unit from any manufacturer, it will be handled by a Industrial rather than Domestic group, and they are excellent.

[Mortis]

As per my experiences with my new ACs, an all Aluminium condenser is a strict NO for me in the future. It corrodes more easily and cannot be repaired by welding like copper so you have to go for a full (expensive) replacement.
Also Im still on the fence about Inverter ACs. I still feel a good 5 star AC would be better in terms of longevity than an Inverter AC. Maybe the 2nd generation of inverters will be better
Anyone know is Amana ACs are available here ? My Dad had got 2 Amana splits from Nigeria, huge floor mounted splits that served us extremely well from the early 90s for the next decade to the early 2000s with barely any problems.

Also, do the Daikin ACs ODU come from the factory with the blue anti corrosion coating ? Or is it extra ? My brother has Daikins in his house and while discussing my condenser coil problems he said that he was charged 4000 bucks extra for the blue coating on the ODU

[lancerlover]

Originally Posted by Aroy

How many of the 7 1.5T units will be operating at a time?
. If more than 3, then you should think of a large VRF unit. That unit can be configured for 3 to 5 tons, depending on the peak demand.
. If you plan to use two or more in the living room, then a 3-phase 3 to 4 ton unit will be more efficient

For larger cooling load, I prefer larger VRF units as they have a low life time cost (and they last a lot longer). If you go in for a large single VRF unit from any manufacturer, it will be handled by a Industrial rather than Domestic group, and they are excellent.

VRF was never considered as at max 3 units will be operating at a time, usually it is down to 2.
The living room is sufficiently cooled by the high rated Panasonics & at times we only operate the one on the desired side of the room.

Installation has to be through company, its a must for warranty.Most ACs come with the basic 3 meter kit, just that some companies allow customers to get their own extra stuff & some don't. LG & Panasonic guys were okay with it, Daikin & Hitachi guys simply refused.

Inverters need better plumbing because of their higher operating pressure.The Model I chose didn't come with anything and I was not okay buying 20 meter malaysian pipe at 2 or 3 x the market price.

One important point that your post made me remember was the equal disribution of the load between the 3 phases in the Db.

[diyguy]

Originally Posted by lancerlover

One important point that your post made me remember was the equal disribution of the load between the 3 phases in the Db.

Good points all but this last one I learnt the hard way. I had multiple flare ups in my DB due to the phase changer and having only two phases current and running three acs at a time. My phase changer melted twice as it was rated only at 40a and I finally got a 32a MCB installed on each incoming phase line prior to the phase changers just to protect the DB. I also switched to 60A phase changers and it's been two years since and no issues.

[sgiitk]

Originally Posted by Lobogris

Is it possible (and advisable) to switch outdoor split ac units (ones housing the compressor) with a different brand? I have a one ton Koryo split in a very large room while there is a 1.5 ton Samsung split unit installed in a tiny room. Would it be alright of we simply took the Samsung outdoor 1.5 ton unit and connected it to the Koryo inside unit (air handler) pipes and vice versa? The ac techs claim it would be fine but I am worried that there might be some weird issue due to incompatibility. It seems like the circuitry is all contained in the inside unit and all it does is issue a command for the outside compressor to switch on and off as needed. Is there something I am missing here?

There are not too many differences, as long as the refrigerant in the same. I had an early Videocon 2TR split. It became prone to frequent failures due to a sensor. The dealer got the company engineers from Lucknow, but the problem became frequent. I was advised by an experienced mechanic that I should change to indoor unit. So I ended up with a Voltas indoor unit with the Videocon outdoor one. I think I used it for over five years.