Team-BHP - The home / office air-conditioner thread

Quote:

Originally Posted by sgiitk (Post 3415812)

I use a 24" fan (use low speed and do not make the high speed) with a large enclosure. I have installed in the staircase landing. Keeps the entire house (>2000sq ft) cool. The stairwell works as a ready made duct.

Hi Sgiitk
Need your help and advice. I also have a 24inch industrial exhaust fan based cooler which runs at 900rpm. Problem is that it is quite noisy when it runs. I earlier had a 700rpm fan in the same setup, which was very quiet. When that fan failed I replaced it with a 900rpm fan. Can you suggest any way to reduce the fan speed and the noise. I have tried Triac based dimmers but they cause the fan to hum and also heat up. I have heard VFDs can work but they area really expenive. The motor runs at 450w. Look forward to your suggestions!

Quote:

Originally Posted by jacksons (Post 3415617)

Gurus please guide me, I want to buy inverter AC's.
Please tell me which once ?

jacksons, I guess you made a good decision in buying inverter a/c. I was using a 12 year old 1 ton Hitachi Window a/c before. Last year in the peak of summer it conked off. The problem with window a/cs are

1. Noisy
2. Compressor cuts off once cooling is reached which results in lot of fluctuations in temperature in the room and can result in disturbed sleep
3. The power bill increase just because of the a/c was Rs.2500 to Rs.3000 per month in the three summer months in Bangalore for 12 hour use per day. The consumption was probably much higher because this is a old a/c when there was no star rating concept.

This year I installed a Daikin 1.5 ton split inverter a/c and the difference is immediate. Following are the observations

1. The machine is super -silent inside the room. Even outside, the noise level is much lower compared to the LG a/c installation which my neighbor has done.
2. No compressor cut off and on intermittently. Hence a uniform cooling depending on set temperature is maintained inside the room for the entire duration of night. Good sleep with minimal disturbance.
3. The power consumption last month was about Rs.900 above my usual consumption for 12 hours use everyday. This beat my expectations and am glad the old a/c conked off.

The above must be true with any inverter a/c and not specifically Daikin brand. But I guess the little extra money that you have to spend in investing in an inverter a/c is worth it.

Warning to fellow Chennai members: Avoid Rathna Fan House and Panasonic

Last week, I bought a Panasonic Inverter Chrome A/C from Rathna Fan House, Chennai who is one of the biggest A/C dealers in Chennai and is also listed as one of the "Panasonic A/C Exclusive" dealers and was told at the time of purchase that the A/C would be installed by the authorized service centre guys.

The A/C was delivered and installed the next day when I was not at home. Later got to know from my wife that the lines were not evacuated, instead some gas was purged into the atmosphere.

I raised a case with the Panasonic helpline. They came back telling me that the A/C has been installed by some 3rd party and not by authorized service centre and hence would not be covered under warranty at all. Tried reasoning with the Panasonic helpline but the case has been closed.

It's really disappointing to know within a week of purchase that my A/C is out of warranty cover for no fault of mine. Feel let down by Panasonic and the dealer.

Quote:

Originally Posted by Behemoth (Post 3415861)

Hi Sgiitk
Need your help and advice. I also have a 24inch industrial exhaust fan based cooler which runs at 900rpm. Problem is that it is quite noisy when it runs. I earlier had a 700rpm fan in the same setup, which was very quiet. When that fan failed I replaced it with a 900rpm fan. Can you suggest any way to reduce the fan speed and the noise. I have tried Triac based dimmers but they cause the fan to hum and also heat up. I have heard VFDs can work but they area really expensive. The motor runs at 450w. Look forward to your suggestions!

I use a triac based regulator and live with the speed variations, since an induction motor tries to lock on to the mains frequency. I was almost scared into going for 900rpm since supposedly knowledgeable people told me that even a 900rpm is unlikely to work for the house. Incidentally, my fan is GEC.

Quote:

Originally Posted by sgiitk (Post 3416254)

Hello Prof,

I also want a similar setup in my house in Lucknow.

Can you please guide me. What all components do I need?

Thanks in advance.

P.S - I have no prior knowledge regarding the matter.

Quote:

Originally Posted by skdking (Post 3416465)

Hello Prof,

I also want a similar setup in my house in Lucknow.

Can you please guide me. What all components do I need?

Get a 24" fan - GEC is supposed to be the best - low speed, ie 700 rpm preferred.
Get a 1/8 - 1/8 hp or so water lifting pump. This can be tricky since almost all available are in the market immersables. But these are available.
Get an enclosure with tank and cover made (mine is about 6' x 2-1.2' x 5' (tall). Three sides. The small enclosures sold will not suffice. Cooling depends a lot on the enclosure size.
Find a decent place in a stairwell or a central verandah. This will sure housewide distribution.
Now ideally make an opening and fix the fan to the wall (much quieter). Make sure to provide for a cover (off season) an grill.
Get the system assembled, and you should be in business. Adding a regulator (not a ceiling fan one) may not be a bad idea.
I also have a float valve with plumbing to feed the tank.

Quote:

Originally Posted by sgiitk (Post 3416957)

...
Now ideally make an opening and fix the fan to the wall (much quieter). Make sure to provide for a cover (off season) an grill.
...

Thanks for the immediate reply, Prof.

So your cooler provides forced circulation to the house. Very effective indeed.

Can I use this setup in reverse to suck in hot air through a GEC fan (without a cooler) fixed in outward/reverse direction?

Quote:

Originally Posted by Zappo (Post 3415542)

If possible try to switch over to a Split. Window ACs are easier to install but are a bit of a pain over a period of time. They will rattle, squeak and create a racket. Besides being costlier on the pocket (to run). Look at Daikin. Good ACs for the price. Similar O'Generals will work out a little costlier.

By the way, Check the declared consumption numbers for the 5 star window AC. I won't be surprised if you find that it is closer to the consumption figures for a 3 star split! To give you an idea, a Daikin Inverter Split 1 ton AC when run at 25*C for 8 hours every night costs you as less as Rs.550 to 600 per month at an average unit price of Rs4!

Actually, the Window ACs by design are inherently inefficient. Cooling unit and the heat exchangers in the same box (front and rear) is never going to be very efficient any how.

Check whether the entire body is plastic or it's the from grill and the top. Not that it matters much as these parts too will be exposed to the sun. However, I think most ACs nowadays come with thse parts made of plastic. Its the same with Daikin, Samsung and LG. Can't recall Panasonic...

Split is actually more difficult to install. I had seen the circus they did to install my split. I also realized once again that day that life has little value in this country. :p

Dear Zappo,

Many thanks for your detailed explanation. As you rightly mentioned its a circus when its comes to installing split AC. I did experience the same while installing my 2 Ton General AC.

Yesterday, i purchased and installed window 1.5 T General (3 star). I truly didn't have the patience to bear that circus again stupid:, hence went ahead with Window type.

One word "Superb" for the General Ac. The cooling itself is poles apart when compared to other brands AC i have in the house including Hitachi.

Having said that there are cons of Window Ac like Noise, Power consumption etc... but in this world very thing has its own Pros and cons.

The total damage done was 27k (4k buy back) + 2.5k (stab). Its on the higher side when compared to Voltas, LG or samsung but i hope it would last long.

Thanks

Amit