new ac consuming 20% more power.

Om Kumar

Recruit
i bought a new hitachi 3star 1.5ton slip ac (model no-rau318hwdd) neo3200. its consuming lot more power than mentioned in the unit about 2100watt and mentioned power consumption is 1630watts. Cooling too is not that much according to the cooling capacity of the ac (its about 5300w). I have also called the service center people they came and checked the unit and said its working fine the grill temperature was found around 8degree Celsius and the amp consumption after running the condenser for 10min was recorded to be 7.1amp and the mentioned current consumption is about 7.4amps. outdoor temperature was about 33degree Celsius when amp consumption was tested. i don't have any device to test amp consumption or grill temperature right now.
SO my QUESTIONS are:-
is the ac working fine and these readings are normal?
is the Freon level low?
any other fault?
 
A power/energy meter can give you those figures.

Any induction device consumes more power during startup... in this case, it could be 2.1K.

Now, unless OP has full AC specifications from the manufacturer, it's difficult to say if something is wrong with his AC.

Or he needs to find another person using the same AC in his area and compare the figures.
 
7.5A sounds about fine.
You need to bear in mind that a good AC will need to run its compressor a lot less than a poor quality one to maintain the same temperature.

The only way to validate if the AC is running at proper efficiency is to check the KwH consumption over a given time period (say 8 hours) for maintaining a given temperature (say 24C) and to compare it against a similar reading obtained from another AC installed in a similar room in the same area

A ghetto way to do this would be to check the average power consumption of your household for say 10PM to 8AM without the AC (from the units consumed reported by the power meter)
Obtain the same set of readings next day with the AC running from the same time period at 24C

Perform a similar exercise for another room and compare the findings

For comparisons sake , here are my power readings from last night (The big spikes are the AC compressor kicking in and out to maintain 24C (so should give you a sense of how long the compressor runs overnight - For a very cooling efficient AC, you would see a bigger gaps between the spikes)
+ the small spikes are the fridge compressor while the super big spikes in the morning are the espresso machine :p

Watts
Capture.JPG

KwH
Capture1.JPG
 
@Om Kumar Have you connected the AC directly to the mains or to some voltage stabilizer kind of device?
If its not connected directly to the main then some stabilizers use more power than the device which is connected to it. More means considerably more ...
 
I used my energy meter for the calculation part I used the method mentioned below:-
Steps:-
1) switched off all other appliances and lights i mean everything which is connected to the main supply
2)disconnected ac from the stabilizer and connected it with the mains directly
3)checked the the voltage with the help of a multi-meter reading was approx 230volts
4)turn on the ac and wait for 20min so that load on the compressor reduces (i know ac consume more power during startup)
[now how i calculated the power consumption]
my energy meter is have a blinking led and 3200 blink is equal to 1000watt
so i counted time taken for 100 blinks
divide 100 by the time take for 100 blinks it will give power consumption per second
took 3 readings and calculated the mean for reducing the error
then multiply power consumed per second with 60x60. it will give power consumed per hour
simple :)
and meter is accurate i have tested that also.
one more thing i forgot to mention no moisture is coming out of the drain pipe
 
I used my energy meter for the calculation part I used the method mentioned below:-
Steps:-
1) switched off all other appliances and lights i mean everything which is connected to the main supply
2)disconnected ac from the stabilizer and connected it with the mains directly
3)checked the the voltage with the help of a multi-meter reading was approx 230volts
4)turn on the ac and wait for 20min so that load on the compressor reduces (i know ac consume more power during startup)
[now how i calculated the power consumption]
my energy meter is have a blinking led and 3200 blink is equal to 1000watt
so i counted time taken for 100 blinks
divide 100 by the time take for 100 blinks it will give power consumption per second
took 3 readings and calculated the mean for reducing the error
then multiply power consumed per second with 60x60. it will give power consumed per hour
simple :)
and meter is accurate i have tested that also.
one more thing i forgot to mention no moisture is coming out of the drain pipe

Hi,
If you have the electronic meter, one can cycle through different features like voltage, current (A), power (kw), Power factor (PF) etc. KW will give exact power consumption of you AC unit. We had one v-guard double booster stabilizer and it just loves to drink more juice. It consumes 100% more power than actual appliance. As you mentioned that the unit has been tested without stabilizer, please check the reading (kw). Also check for current leakage in any joints.
 
I think it is normal for any AC to work at 20% more power for the first 30-60 mins so that it can quickly bring down the ambient temp to the desired level. The power & duration depends on the difference in outside, inside & the desired temp. Besides, your indirect method of calculation is prone to errors & inaccuracies.

I've two 1T and one .75T Panasonic 5 star ACs. See the graph below, phase 1 & 2 has 1T and phase 3 has .75T, see the black line, it starts with 1.2 KW and then all three AC settles around 450-500 watts to maintain the temp.

kkcHK8X.jpg
 
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I've two 1T and one .75T Panasonic 5 star ACs. See the graph below, phase 1 & 2 has 1T and phase 3 has .75T, see the black line, it starts with 1.2 Kwh and then all three AC settles around 450-500 watts to maintain the temp.
What sensors are you using for three phase monitoring/plotting
 
Thanks for confirming
I use a different setup albeit similar in the sense that it uses a single clamp sensor on the ground wire to give a reading for all 3phases.
While it is reasonably precise (i get around 6-7% delta) but I guess a clamp sensor will always have limitations
 
Aha okay. All 3 phase monitoring makes it little easier in keeping track of power usage of almost everything in the house. I've seen your other thread on automation and liked it. Even I wanted to do something like that in future but with something commercially cheap smart hub, and I integrates easily with upcoming Google chirp (like Amazon Alexa).
 
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