Refrigerator energy consumption

blr_p

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If you are looking to invest so much, do also take a look at some Industrial offerings. I bet you can find some 600L options between 60-80k. They will however be without a freezer section. Good thing about them will be easy repairability and much more sturdier components. They also come with a flexible rack system.
yeah i've seen your early post with blue star. We need a freezer though.

My first preference would be two fridges of the same 260 -280Lts as there is redundancy in case of a failure. But we don't have space for another in the house so decided to get a big one.

Appliance buys like this i suspect are distress purchases as either a fridge or a washing machine conks out suddenly and you are left with either a speedy fix of some PCB whose only problem is some blown cap somewhere or an outright replacement.

The kelvinator is still working, i notice now i don't get shocked anymore when touching the handle. How long it lasts is an open question. But the grace period has been helpful.[DOUBLEPOST=1557674095][/DOUBLEPOST]
What is the source and model of this meter?
https://www.amazon.in/gp/product/B078WQ261L

I have it on a power strip which i can plug any device to. Home made kill a watt without true rms. So only nice sine waves. This model can handle up to 20A which is good enough for any residential appliance testing. The kW can be reset so you get an idea how many units a device consumes over any time period.
 
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blr_p

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Real world power consumption varies with ambient temperature amount of times you open the fridge and what temperature you want to maintain. In the samsung when there is nothing in the freezer I convert it to fridge. The hottest temperature option in fridge is 7c and coldest temperature is like 1c, where as the freezer works its hottest -15c to -23c coldest, so when its set to fridge mode the compressor consumes less power, even though it's inverter its Off for the majority of the time during night when I usually get to know by the sound of the compressor.

More then the compressor consumption, the highest power consumption I get is by the coils melting the frost.
Going by the BEE website, how many stars can make a difference

eg. a two star 260 Lt (GL-N292KPRR) consumes 275 units compared to a 471 Lt 4 star, one i picked at 237

Course there is always the argument whether a higher rated fridge cools adequately ? and when you do make it work it does not save as much as claimed. This will require a study of BEE's testing methodology. How close it approximates real world use or in short one's own use.

https://www.beestarlabel.com/SearchCompare/Searchandcompare

Does that show up with user selectable model lists ? otherwise you have to start from the home page and look for search & compare
 

blr_p

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The new fridge arrived and been enjoying it for the past few days.

20190515_153416.jpg 20190516_133709.jpg 20190516_133802.jpg 20190519_215445.jpg 20190520_145829.jpg 20190519_190810.jpg

Got it from a LG brand store on the outskirts of the city. With the old fridge exchange it worked out to 55k. The Amber steel is more of a darker brown colour than a lighter shiny copper colour. Well, it varies it looks brighter in more shiny light. I like the look.

Box sticker indicates it was built less than a month back and going by the address i assume some where in Pune. It has temperature controls on the door so no fumbling for dials inside. I also like that it has temperature settings for fridge & freezer instead of meaningless numbers. What does a setting of "4" mean in terms of temperature in the fridge, in the freezer ? Samsungs have these temp settings on the door for lower capacity fridges but with LG you only get them with capacities 400 Lt and above. My thermometers show it tracks pretty close to what it says but you can also see the min/max variations during the day in above photo. This is the reason the manual says not to store any temperature sensitive medicines as the tolerances are looser in consumer fridges than with commercial fridges made for this purpose. It goes without saying that such fridges will not have any star rating as they are intended to be running pretty much constantly.

smart thinkq 1.jpg smart thinkq 2.jpg smart thinkq 3.jpg

This fridge can be connected to WiFi. The app shows what the current freezer & fridge temperature settings are. It allows to change them and to switch on the express freeze feature. Hygiene fresh is an extractor fan that works every hour for a few minutes to remove bad smells in the fridge. HF has a power setting also makes it run more frequently. I left it on auto. There is a smart diagnosis feature that tells you the general status of the fridge. It also mentions how many times on average the door was opened. 41 times a day seems a bit high maybe we were a bit over enthusiastic when it arrived. It mentions the fridge should be loaded only to 70% for max efficiency so keep that upper limit in mind when going for a new fridge. 70% max loading seems like a good rule of thumb whether it be washing machines, mixies or a fridge. Our last fridge was packed to at least 90% (!)

20190509_200730.jpg 20190509_200650.jpg 20190509_200958.jpg

When browsing in the shops I noticed this thing on the top of LG fridges. Its only there for LG fridges with capacity of 300 -500 litres. Under 300 or over 500 the top is clear and flat. Apparently that is where the main motherboard is situated. Sticks out about an inch. So if anything goes wrong they replace the board from there. It's easy to access so a replacement is a half hour job.

I've never owned an inverter fridge before let alone a "linear" inverter fridge so had no idea what sound it makes when the compressor starts. I was used to the sound of the kelvinator and thought this new fridge should also make a sound but maybe a bit less. So after the delivery guys installed it, waited a several hours as instructed before switching it on and then recorded what is sounded like. There was this buzzing sound that could be heard. Sounds like this

I thought it was fairly loud and it could even be heard a room away. Once the set temperature was reached it shut off only to come on when temperatures rose. I started to wonder whether it was installed correctly and sure enough they never touched the leveling legs in the front. The manual states the fridge must not be level like a washing machine rather the front should be raised in relation to the back anywhere from 6 to 13 mm. Never knew the front had to be raised before, our previous fridge certainly was not setup like that and i suppose is why the compressor had to work harder and longer.

I settled for 1 cm higher in the front. The reason to raise the front slightly is it allows the condensed coolant to naturally flow back towards the compressor as well as making the doors shut by themselves if left open. If you fridge door does not shut by itself when open then the front needs to be raised a bit. Got it done, made sure it was level left to right then waited to see if the buzzing sound stopped. Nope, no difference at all but at least the doors shut by themselves now.

This went on for a few days until the demo guy arrived. These guys are repair people and the first question i asked him was whether this sound was normal for a new fridge. He said the condenser pipe can get pinched during delivery due to shaking. So he opened up the back plate and just moved the thin pipe between the condenser and the evaporator fins. All of a sudden the sound stopped. Now it sounded like this

Hear anything now ? no. There is almost nothing. So that is what a "linear" inverter sounds like. Nothing. You can sleep next to this thing and not know when it switched on. I was a bit surprised so he told me to put my hand on the compressor and could feel it vibrating. The power meter showed it was drawing approx 60W which is the max power i've seen it drawing for the set temperatures. WOW! completely silent fridge you can make out a faint hum and the fans moving air around inside but even this is quite faint and you'd have to listen for it at the back of the fridge. Without a power meter attached it would not be possible to tell if this thing was even working. Earlier was a bit upset as i thought i had a faulty product. All good now.

20190515_192437.jpg 20190515_191836.jpg 20190518_191710.jpg

So how much power does this thing consume over 24h ?

If we look at the BEE sticker it says 237 units/year which works out to around 0.65 units per day. Interesting thing is this sticker is dated 2019, the black variant i'd seen of a smaller 437 Lt unit said 2018. Good, at least its current.

At a freezer temperature setting of -18°C and fridge temperature of 3°C, the power meter recorded around 1.1 kW after 24 h. After a few days i noticed this power draw was fairly constant. So at these settings it consumes half my previous fridge which is good.

As to why its higher than BEE's rating there could be several reasons
- does BEE open the door at all ? or is that a reading with doors shut for the entire day.
- ambient temperature could play a role. The fridge should be in a well ventilated area. My kitchen has windows and doors are kept open. I suppose it is ventilated if not well ventilated. But the ambient temperature right now is 28°C in the kitchen. In a cooler room the fridge might work less
- what temperature settings does BEE use. I suppose i could use less power if i raise freezer from -18 to -15 and fridge from 3 to 7°C. It would work less. I will do a power consumption test in the coming days at lowest & highest temperature settings to see the difference.

Right, now the fridge is fairly empty but it will fill up with time. So power consumption might rise a little more.

The demo guy wanted to sell me an extended warranty that worked out to around ~Rs.3.3k per year which i declined as i don't expect any issues within the next five years and should anything happen i have a year's warranty to cover manufacturing defects anyway. But i did ask him what i got for that price. He said if any parts had to replaced they would be covered after the initial warranty expired. Which is only for a year. And that he'd come over every three months to clean out any dust that accumulated at the back. This last bit is interesting. If any dust accumulates on the evaporator coils it will affect efficiency. Though i doubt every three months is necessary. Maybe once a year so i asked him how much per house call and he said Rs.650 which i will do instead. Once a year have him come over and give the back a good clean.

The instruction manual says the minimum size inverter to power this fridge is 600VA with a 120AH battery. I can believe this. At -18 & 3 for fridge, it consumes a max of around 65W. And when the compressor starts up it draws power very slowly, you can see the power meter taking almost a good couple of minutes to reach max power. There is no starting current for this compressor. The demo guy told me it defrosts itself every 9 -13h but i've yet to see power consumption cross 65W

Awesome fridge :)
 
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adder

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That's a big fridge, I guess no stainless steel color options available. White and stainless steel hide finger prints better.

You need to check the real time power consumption during the defrost cycle, which will be higher, those heating coils are still ancient.

Your fridge is certainly quieter then my samsung inverter fridge. Hell my panasonic non-inverter fridge is quieter then my samsung.
 

adventureguy

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The new fridge arrived and been enjoying it for the past few days.

View attachment 80293 View attachment 80294 View attachment 80295 View attachment 80296 View attachment 80297 View attachment 80299

Got it from a LG brand store on the outskirts of the city. With the old fridge exchange it worked out to 55k. The Amber steel is more of a darker brown colour than a lighter shiny copper colour. Well, it varies it looks brighter in more shiny light. I like the look.

Box sticker indicates it was built less than a month back and going by the address i assume some where in Pune. It has temperature controls on the door so no fumbling for dials inside. I also like that it has temperature settings for fridge & freezer instead of meaningless numbers. What does a setting of "4" mean in terms of temperature in the fridge, in the freezer ? Samsungs have these temp settings on the door for lower capacity fridges but with LG you only get them with capacities 400 Lt and above. My thermometers show it tracks pretty close to what it says but you can also see the min/max variations during the day in above photo. This is the reason the manual says not to store any temperature sensitive medicines as the tolerances are looser in consumer fridges than with commercial fridges made for this purpose. It goes without saying that such fridges will not have any star rating as they are intended to be running pretty much constantly.

View attachment 80300 View attachment 80301 View attachment 80302

This fridge can be connected to WiFi. The app shows what the current freezer & fridge temperature settings are. It allows to change them and to switch on the express freeze feature. Hygiene fresh is an extractor fan that works every hour for a few minutes to remove bad smells in the fridge. HF has a power setting also makes it run more frequently. I left it on auto. There is a smart diagnosis feature that tells you the general status of the fridge. It also mentions how many times on average the door was opened. 41 times a day seems a bit high maybe we were a bit over enthusiastic when it arrived. It mentions the fridge should be loaded only to 70% for max efficiency so keep that upper limit in mind when going for a new fridge. 70% max loading seems like a good rule of thumb whether it be washing machines, mixies or a fridge. Our last fridge was packed to at least 90% (!)

View attachment 80303 View attachment 80304 View attachment 80305

When browsing in the shops I noticed this thing on the top of LG fridges. Its only there for LG fridges with capacity of 300 -500 litres. Under 300 or over 500 the top is clear and flat. Apparently that is where the main motherboard is situated. Sticks out about an inch. So if anything goes wrong they replace the board from there. It's easy to access so a replacement is a half hour job.

I've never owned an inverter fridge before let alone a "linear" inverter fridge so had no idea what sound it makes when the compressor starts. I was used to the sound of the kelvinator and thought this new fridge should also make a sound but maybe a bit less. So after the delivery guys installed it, waited a several hours as instructed before switching it on and then recorded what is sounded like. There was this buzzing sound that could be heard. Sounds like this

I thought it was fairly loud and it could even be heard a room away. Once the set temperature was reached it shut off only to come on when temperatures rose. I started to wonder whether it was installed correctly and sure enough they never touched the leveling legs in the front. The manual states the fridge must not be level like a washing machine rather the front should be raised in relation to the back anywhere from 6 to 13 mm. Never knew the front had to be raised before, our previous fridge certainly was not setup like that and i suppose is why the compressor had to work harder and longer.

I settled for 1 cm higher in the front. The reason to raise the front slightly is it allows the condensed coolant to naturally flow back towards the compressor as well as making the doors shut by themselves if left open. If you fridge door does not shut by itself when open then the front needs to be raised a bit. Got it done, made sure it was level left to right then waited to see if the buzzing sound stopped. Nope, no difference at all but at least the doors shut by themselves now.

This went on for a few days until the demo guy arrived. These guys are repair people and the first question i asked him was whether this sound was normal for a new fridge. He said the condenser pipe can get pinched during delivery due to shaking. So he opened up the back plate and just moved the thin pipe between the condenser and the evaporator fins. All of a sudden the sound stopped. Now it sounded like this

Hear anything now ? no. There is almost nothing. So that is what a "linear" inverter sounds like. Nothing. You can sleep next to this thing and not know when it switched on. I was a bit surprised so he told me to put my hand on the compressor and could feel it vibrating. The power meter showed it was drawing approx 60W which is the max power i've seen it drawing for the set temperatures. WOW! completely silent fridge you can make out a faint hum and the fans moving air around inside but even this is quite faint and you'd have to listen for it at the back of the fridge. Without a power meter attached it would not be possible to tell if this thing was even working. Earlier was a bit upset as i thought i had a faulty product. All good now.

View attachment 80306 View attachment 80307 View attachment 80308

So how much power does this thing consume over 24h ?

If we look at the BEE sticker it says 237 units/year which works out to around 0.65 units per day. Interesting thing is this sticker is dated 2019, the black variant i'd seen of a smaller 437 Lt unit said 2018. Good, at least its current.

At a freezer temperature setting of -18°C and fridge temperature of 3°C, the power meter recorded around 1.1 kW after 24 h. After a few days i noticed this power draw was fairly constant. So at these settings it consumes half my previous fridge which is good.

As to why its higher than BEE's rating there could be several reasons
- does BEE open the door at all ? or is that a reading with doors shut for the entire day.
- ambient temperature could play a role. The fridge should be in a well ventilated area. My kitchen has windows and doors are kept open. I suppose it is ventilated if not well ventilated. But the ambient temperature right now is 28°C in the kitchen. In a cooler room the fridge might work less
- what temperature settings does BEE use. I suppose i could use less power if i raise freezer from -18 to -15 and fridge from 3 to 7°C. It would work less. I will do a power consumption test in the coming days at lowest & highest temperature settings to see the difference.

Right, now the fridge is fairly empty but it will fill up with time. So power consumption might rise a little more.

The demo guy wanted to sell me an extended warranty that worked out to around ~Rs.3.3k per year which i declined as i don't expect any issues within the next five years and should anything happen i have a year's warranty to cover manufacturing defects anyway. But i did ask him what i got for that price. He said if any parts had to replaced they would be covered after the initial warranty expired. Which is only for a year. And that he'd come over every three months to clean out any dust that accumulated at the back. This last bit is interesting. If any dust accumulates on the evaporator coils it will affect efficiency. Though i doubt every three months is necessary. Maybe once a year so i asked him how much per house call and he said Rs.650 which i will do instead. Once a year have him come over and give the back a good clean.

The instruction manual says the minimum size inverter to power this fridge is 600VA with a 120AH battery. I can believe this. At -18 & 3 for fridge, it consumes a max of around 65W. And when the compressor starts up it draws power very slowly, you can see the power meter taking almost a good couple of minutes to reach max power. There is no starting current for this compressor. The demo guy told me it defrosts itself every 9 -13h but i've yet to see power consumption cross 65W

Awesome fridge :)
yeah I was getting concerned when you mentioned sound from fridge. My friend has an lg intverter fridge as well and we couldnt tell if it was on or off since its so silent.
 

blr_p

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That's a big fridge, I guess no stainless steel color options available. White and stainless steel hide finger prints better.

You need to check the real time power consumption during the defrost cycle, which will be higher, those heating coils are still ancient.

Your fridge is certainly quieter then my samsung inverter fridge. Hell my panasonic non-inverter fridge is quieter then my samsung.
White isn't available but silver is and only in 3 star. I don't know why LG does this with this particular model. Same story with the 437Lt one as well. The silver 420 Lt model is four star but then you have the back lit lighting in the fridge. Here lighting is consistent, freezer as well as fridge. Also shelf layout is less cluttered.

People found it big when it arrived but i think this is better than not big enough or small. We will get used to it.

The "linear" inverter increases efficiency as well as reduces noise. The LG fridges labelled as "smart" inverter as opposed to "linear" still use reciprocating compressors like samsung.

One guy made a review of his samsung and states he expressly went with Samsung because he saw people complaining in yutube comments from the states about life of this "linear" inverter. Packs up in a few years. Well, if this is the case warranty will take care of it and labour charges aren't much. So i'm willing to risk it.

How to test power consumption when defrosting occurs ? I have no idea when the defrosting happens and my power meter unfortunately does not have any min/max feature.
 
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rdst_1

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If you have calculated the dimensions of the actual space, please let me know. For some reason, all of the refrigerators in the market these days seem rather small to me compared to the capacity mentioned by the manufacturer.
 

blr_p

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If you have calculated the dimensions of the actual space, please let me know. For some reason, all of the refrigerators in the market these days seem rather small to me compared to the capacity mentioned by the manufacturer.
This measurement business is quite tedious, wish they included it in the manual. Check the pdf of the models i looked at.

Manufacturer only lists the gross volume, what you want is the storage volume. Then reduce that by 30%. You can find these on the BEE website for models that have a star rating.

Internal dimensions you need a measuring tape, BEE only gives one figure.
 

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adder

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How to test power consumption when defrosting occurs ? I have no idea when the defrosting happens and my power meter unfortunately does not have any min/max feature.
When the fridge is warm to touch on the sides (due to heating coils), that's when you take the reading .
 

blr_p

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When the fridge is warm to touch on the sides (due to heating coils), that's when you take the reading .
How often does it happen say in a week with your fridge ?
 

blr_p

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It's happens daily in both my fridges.
right, the demo guy said once every 9 -13h but i never feel the sides gets warm so far. It might be too early for an auto defrost as its new.

Anyway the power meter will remain connected for more time so we will see.
 

rdst_1

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Usually the defrost timer will have the timing written on it. I am using a third party one recommended for my LG fridge and it shows that the heating cycle will be for 12 minutes every 9hr 40 minutes.
 

blr_p

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12 minutes out of every 10h is going to be tricky to catch :)
 

adder

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While I have not timed the defrost time, I can safely say its more then 20min, varies from summer to winter.
 

rdst_1

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While I have not timed the defrost time, I can safely say its more then 20min, varies from summer to winter.
Maybe the technology has changed if the time varies on yours and it might be more sensor driven now. Mine is a 17 yr old fridge. The defrost timer is just an electric timer on mine. The time can't vary. It is an electric relay which runs on a timer. After every 9h40m it switches the power supply from the compressor to the heater. After 12 minutes it switches it back and the cycle goes on and on.
 

blr_p

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I think i 've figured it out, the power meter might not show min/max but the thermometer display unit does. If you see the photo i posted above you will notice a temperature range of -6 to -20 for the freezer.

I found this range a bit odd and it was hard to tell whether it was occurring due to normal use when we open the freezer door or not. But after observing for some time without the freezer door being opened it still dropped to -6.

So that must be when the defrosting is occurring ;)

I managed to catch it when it was at -6 and noticed the power consumption had climbed to 75W. Sides weren't any warmer than usual. I've not noticed any warming of the sides at all.

I need to catch it when the temperature drops from -18 as that is when the heater will be at max.

My impression of inverter compressor WAS that its constantly running and then increases when required instead of stop/ start like a conventional compressor. But i notice there are times it runs then it gradually slows down and eventually stops as the power draw is like 3W only to start up again later on and slowly climb to 65W.
 
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blr_p

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So i did some testing at lowest and highest power over a few days and averaged it out.

At the lowest setting Freezer -15 & Fridge 6, power averaged 0.9 units per day. That is the lowest i can take it so i don't know where the 0.65 units per day from the BEE label comes from. There is no option to switch only freezer or fridge off. Both are on

The default setting Freezer -18 & Fridge 3, power averaged 1.1 units per day

At the highest setting Freezer -23 & Fridge 0, power averaged 1.3 units per day

So the spread is 0.9 up to 1.3 units per day

My thermometers confirm temperature as set is what it is really. Eventually they settle on the set temperature levels.

As for defrosting, i managed to catch it when temperature was rising and found it got up to 110W on the -23 setting and 80W on the default -18 setting. It does not stay at that max level for long, it rises up there then drops slowly.

20190524_020739.jpg

Regardless of what the sticker says, the sides of the fridge do not heat up during defrosting, its a constant 30 degrees all over.
 
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blr_p

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Finally, managed to catch it at the start of the defrost cycle

20190619_083031.jpg

Back to the default -18 for freezer and 3 for fridge.

The pf at 0.99 shows its a resistive load and it gets up to 210W. Stays there for a half hour. Sides don't heat up.