[sagarpadaki]

Originally Posted by NPV

Noob electricals question.
Our Daikin split AC stopped working earlier this week and the diagnosis is that main boards of both indoor and outdoor units have gone bust. We had a power surge few days ago but the AC wasn't being operated at the time though the wall socket's switch was ON. Connection is from wall socket to V-Guard stabilizer to AC indoor unit. Wondering why the stabilizer didn't cut off output to the AC during the surge ? What could be a possible solution to avoid this in future ? (The circuit also has a MCB)

Stabilizer needs some time to react to the surge. The surge would have done the damage by the time the stabilizer could react. You need a spike buster before the stabilizer since the spike buster will cut off the supply first in case of a surge.

[Thad E Ginathom]

Originally Posted by sagarpadaki

Stabilizer needs some time to react to the surge. ...

And the same thing applies to the MCB.

Sorry to hear of your loss. Power surges can be expensive.

[Chetan_Rao]

Originally Posted by NPV

....Wondering why the stabilizer didn't cut off output to the AC during the surge ? What could be a possible solution to avoid this in future ? (The circuit also has a MCB)

Commercially available stabilizers are electromechanical in nature (that's why you hear the relays clicking when they're in action) with a reaction time in milliseconds (thousandths of a second). The best ones you can find will still have reaction times around 10 ms.

Power spikes/surges occur in an entirely different and far smaller timeframe (nanoseconds, that's a billionth of a second), so your stabilizer is useless against a power spike/surge, it's not designed for it.

You need a spike/surge protector before the stabilizer on the A/C input.

[NPV]

Originally Posted by Chetan_Rao

You need a spike/surge protector before the stabilizer on the A/C input.

Any examples of such products ?
Will the regular multi socket extension cord (power strip) with surge protection via a fuse do the job ?

[Prowler]

Originally Posted by NPV

Any examples of such products ?
Will the regular multi socket extension cord (power strip) with surge protection via a fuse do the job ?

I have mentioned about this earlier here. Electronic gadgets don't take kindly to transients and surges. Your stabilizer will not protect your precious gadgets from such transients.

What you need is a Surge Buster which uses a MOV (metal oxide varistor). When it comes to high current consuming Airconditioners, Washing machines and other equipment, do NOT use ordinary extension cords. You need something that can carry at least 20 A safely.

So what this means is you need to buy a 4pole Surge Protection Device (for 3 phase supply) which can be fitted in your mains input box. These devices have typical response time of 25 nS. And they can 'sink' 20000 A.

They will protect your electrical gadgets from even lightening strikes in the supply line.

We used to suffer electronics causalities regularly every monsoon in Madras until we rigged these devices in our mains line. Not just that, we even took the trouble of fitting a MOV 275 V/20A device for every socket with a MCB so that even locally induced transients and surges can be arrested before they do any serious damage.

[diyguy]

Originally Posted by Prowler

So what this means is you need to buy a 4pole Surge Protection Device (for 3 phase supply) which can be fitted in your mains input box. These devices have typical response time of 25 nS. And they can 'sink' 20000 A.

Do you mean something like this?
https://www.amazon.in/dp/B01N78G0JE/..._dNIECb2SR02P0

[Prowler]

Originally Posted by diyguy

Do you mean something like this?
https://www.amazon.in/dp/B01N78G0JE/..._dNIECb2SR02P0

Yes. But there are other companies like Schneider too. Whilst at it make sure that you have a proper earth/ground. These devices need a low impedance/resistance ground for proper operation.

[NPV]

Originally Posted by Prowler

But there are other companies like Schneider too. Whilst at it make sure that you have a proper earth/ground. These devices need a low impedance/resistance ground for proper operation.

Thanks. Can you please share details of the specific products (Schneider MOV) that you have used both at main input (is it at the cut-out in the street pole from your connection is tapped or is the device fixed at the main meter ?) And also the MOV outlets to which the appliance/electronic device is connected ?
We have a single phase electric connection, not 3 phase, not sure if the MOV products to be used will be different for our usage compared to what you have used for the 3 phase connection.

[Prowler]

Originally Posted by NPV

Thanks. Can you please share details of the specific products (Schneider MOV) that you have used both at main input (is it at the cut-out in the street pole from your connection is tapped or is the device fixed at the main meter ?) And also the MOV outlets to which the appliance/electronic device is connected ?
We have a single phase electric connection, not 3 phase, not sure if the MOV products to be used will be different for our usage compared to what you have used for the 3 phase connection.

That is odd. Normally most of the Indian Electricity Boards will provide a maximum of 15 A per phase supply to a house. If you have a single phase supply, the maximum current you can draw is 15 A - limited by your meter. Any overload - above 150% will damage the electronic type meter. The old fashioned cog wheel meter may withstand more short term overload.

A 15 A supply will restrict the load you can use in your house. Please check again your utility Supply line. You should find something like this:
20 A/30 A fuse box per phase feeding your meter. After the meter, it will go towards a switch box and then to small circuit breakers feeding individual lines.

You can buy any good SPD (like this eg: Havel's : https://www.havells.com/en/consumer/...evice-(7).html)
Connect this Surge Protection Device (SPD) after the MCB at the entry point of mains supply. If there is any surge, the SPD will trigger the source to the ground. It is very rare for the device to fail. It can be replaced as a cartridge.

Go to your friendly neighborhood electronics component store and buy one or more of MOV 275/20 . They don't cost much. Ask your electrician to fix this component after the MCB inside your metal socket of your Airconditioner.

[diyguy]

Originally Posted by Aroy

. I bought an LG 5 star dual inverter AC; which had an MRP of 59,000/ + 1,500 for installation; through PAYTM. After all the cashback (PAYTM and ICICI), my cost was around 34K.

Sounds like a great deal. Kindly share the model number if you have it handy. I suppose these deals will now be available post the summer.

[Aroy]

Originally Posted by diyguy

Sounds like a great deal. Kindly share the model number if you have it handy. I suppose these deals will now be available post the summer.

LG-Q18HUZD

The deals change throughout the year, so you have to be on the lookout. I bought my AC in beginning of June, which is middle of harsh summer.

It all depends on the market, and if the appliances are not selling then you will start getting deals, which will keep getting sweeter and sweeter if the sales are dull.

Here is the least expensive model now
https://paytmmall.com/lg-1-5-ton-5-s...hild_site_id=6

But
. Cashback is low (5% vs 13%)
. Installation is not free (added cost of 1,500)
. No cashback from banks (was 2,500 from ICICI and HDFC)

I guess as the summer approaches, the deals will get better

[diyguy]

Need some help with the right procedure to check refrigerant level in a R22 Daikin 1.5T split ac. I called Daikin and they sent a contracted dealer home. I insisted to the guy that my ac is cooling but low and need to ensure gas is topped up.

He did some indoor cleaning for about 5-8 mins and then the outdoor unit he poured water on the heat exchanger coils for about 5 mins. He used the pressure gauge and showed me 40 psi but didn't wait much for the pressure to rise while the compressor was on. He then connected a cylinder of R22 and did not turn it on or off. I was watching keenly, he was on a call and seemed to pretend he did something for a few seconds and told me he finished. He then connected the gauge and waited patiently for the pressure to rise to 60psi. This was unlike in the beginning when he showed me 40psi which he removed almost instantly. I told him I need to see atleast 80psi but he said he cannot add more.

I refused to pay him and told him will check overnight and then pay. The cooling has not improved significantly which one would expect with a full refrigerant level. I had paid him 1150 rs yesterday and have a balance of 500 that I do not intend paying and will ask Daikin to send me another team to measure and topup the gas if needed.

Please let me know if the process of gas checking that he did was correct or he was trying to cheat. Also he claimed that gas filling takes just 1-2 seconds which I totally did not buy. Was he right?

I know 80psi is high but he himself told me it should be at 80psi initially. One thing I noticed is that the power consumption from about 1750w has fallen to 1550w when the ac is running at 18° after the cleaning.

[kavensri]

I have one noob question.
I brought my Mitsubishi Electric AC in 2016. This will be my 4th year running. Previously I have used it for 3 months in a year, average of 4 hours per day.
My question is, do I need to get anything checked up, like gas level? I am not facing any issues with the cooling level, but just wanted to know whether I need to get any preventive service checkup to be done?

[MBond007]

Need some expert inputs.

I am planning to buy a AC for my living room.

Floor: Top Floor (living room becomes heat chamber in summer)
Location: Noida
Area: ~220 sq ft

Estimated Running Time: 3-5 hours daily

My heart beats for Mithshubishi 2.2 Tonne Inverter AC. But at 70K, it is very expensive. Currently Carrier 2 Tonne 3 Star Inverter AC is available for Rs 42K on Flipkart. Panasonic 2 Tonne 5 Star AC is available for Rs 47K, while LG 2 Tonne 3 Star is selling at 49K.

The Panasonic window AC in my bedroom started giving problem after the first year. From PCB failure to gas leakage, it has been plagued with issues from the time the warranty got over. So I am not very keen on Panasonic.
Moreover, since the air in Nodia is very toxic and corrosive, people suggest that the condenser should be robust and have special coating.

Kindly advise which brand should I go for. How about brands like Midea or Whirpool? Are they good?

Originally Posted by kavensri

I have one noob question.
I brought my Mitsubishi Electric AC in 2016. This will be my 4th year running. Previously I have used it for 3 months in a year, average of 4 hours per day.
My question is, do I need to get anything checked up, like gas level? I am not facing any issues with the cooling level, but just wanted to know whether I need to get any preventive service checkup to be done?

I would advise not to tinker with the AC. Mitsubishi ACs are the best in the market and they have a very solid built. Just clean the filter with running water at the beginning of the season.

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[Aroy]

Originally Posted by MBond007

Need some expert inputs.

I am planning to buy a AC for my living room.

Floor: Top Floor (living room becomes heat chamber in summer)
Location: Noida
Area: ~220 sq ft

Estimated Running Time: 3-5 hours daily
....[/b]

I have excellent ownership with LG dual inverter AC. Their service is much better than Hitachi and Daikin (which I still have) and their extended warranty covers all but some rubber parts -
. 2 Service a year
. Gas
. Compressor
. Heat exchangers
. Electronics

So you are covered for 5 years at 16K or so.