12v Fridges - Empirical-ish Collection of Sound Levels

[Shigeta]

While I was researching which fridge I wanted to buy, the sound level was an important consideration since I had considered sleeping in the back of the vehicle near by the fridge. If your intended setup is similar to mine, sound levels are an important part of the decision making process

Unfortunately, I couldn't find even remotely empirical data of real-world sound levels of various fridges. In fact, many manufacturers either refused to give me or did not have this information when I asked. After a lot of searching through rather subjective and ultimately unhelpful information on sound levels, I ended up pulling the trigger on a fridge and took measurements in a repeatable way and I thought I'd share the results and my method of measurements for the community in hopes to both inform and collect more data.

Perhaps this data exists in random threads strewn across the internet or old Facebook posts in a group, but I wanted to create a collection of data that people fridge shoppers can easily search for and reference.

I am certainly not a sound engineer, so if anyone out there has ideas on how these tests can be conducted in a way that will be more helpful, please message me.

If you'd like to see the sound levels gathered so far:
See this Google Sheet. I'll keep this updated as more users post usable measurements.

If you'd like to contribute to the repository of 12v fridge sound levels:
You can post here and/or fill out this Google Form. Responses will be automatically added to the collection of responses.

You'll need the following:

• The fridge in a reasonably quiet place with consistent sound levels (I.e. no barking dogs, lawn mowers, music playing, etc.)
• A decibel meter or Android or iPhone with a free decibel meter app
• A tape measure/ruler

Steps:

1. Make sure the fridge compressor is not running or that the fridge is unplugged.
2. Important: Place decibel meter or phone mic 12 inches / ~30 centimeters away from the compressor vents—usually found on the side or back of the fridge. Try to keep the microphone out of any direct airflow from a fan, if your fridge is equipped with one. Wind noise will skew results.
3. Turn on decibel meter or begin running a decibel meter app to begin seeing sound readings
4. Measure the sound level for at least 1 minute and record the highest reading.
   (Note: Many meters and decibel apps will record the highest lowest, and average readings)
5. Plug in the fridge and wait until the compressor turns on. This can be forced by setting the temp lower and/or opening the door so the compressor kicks on
6. With the meter/phone in the same location, measure the sound levels for at least 1 minute, this time with the compressor running, again recording the highest sound level

Some notes:

• Measuring the sound level of the fridge while running is useless without the "control" measurement of the environment it is in while the fridge is off. Please include both measurements in your results.
• If something loud happens during the recording, such as a dog barking, a car passing, a door closing, a sneeze, a plane flying overhead etc., it may significantly effect the results. Please make sure the sound levels of the environment are as stable as possible.
• Isolating variables
• For greater accuracy, conduct the test several times and take the average of each result. For example, if I measured the highest sound level while the fridge was running as 20 dB, 24 dB, 22 dB, 26 dB over 4 tests, the average would be 23 dB. The formula for calculating average is to add up the results of each test, then divide the sum by the number of tests run. In my case, 20 + 24 + 22 + 26 / 4 tests = 23.

NOTE: Please do not solely post anecdotal "reviews" of your refrigerator. For example, stories such as "My fridge is silent! I've been sleeping next to it for years and I don't hear a thing!" is not very useful for those comparison shopping based on sound levels. While the insight is indeed appreciated, experiences are most valuable when paired with actual data. If you would like to contribute, please at least include your measured test results.

 

[Shigeta]

With all that out of the way, here are the readings I took. Feel free to copy and paste this format for posting your own results.

Refrigerator: Dometic CFX3 45
Environment: Quiet room, trees blowing outside, gardeners quietly buzzing away a few houses down, no HVAC running.
Average peak measurement with fridge off: 31.4 dB
Average peak measurement with fridge running: 38.1 dB
Fridge off vs. running difference: 6.7 dB

 

[67cj5]

I have tested 4 different fridges/brands, but it is not the db which is the issue here it is the frequency or Pitch noise that it effects the loudness of them, Many claim that the sound level is 45db when tested all of them were much lower around 28/29db, Two different fridges both give the same sound level reading but where it all goes wrong is the Fan pitch/Noise, One I can sleep with it under the Bed in the Van/Camper and the other I can here is 12 feet away,

I am making a list of their sound level readings But the noise is not only about having a Low db reading.

Hope that helps.

 

[Shigeta]

I have tested 4 different fridges/brands, but it is not the db which is the issue here it is the frequency or Pitch noise that it effects the loudness of them, Many claim that the sound level is 45db when tested all of them wer much lower around 28/29db, Two different fridges both give the same sound level reading but where it all goes wrong is the Fan pitch/Noise, One I can sleep with it under the Bed in the Van/Camper and the other I can here is 12 feet away,

I am making a list of their sound level readings But the noise is not only about having a Low db reading.

Hope that helps.

That's a reasonable point. Like you experienced, the claims of manufacturers make is one thing, though I hoped to gather real-world data from fridge owners.

Perhaps a recording of each fridge's compressor in environment would be helpful to complement the decibel measurements of each. Heck, even if a company provided a data sheet that documented the pitch, frequency, or resonance of a compressor, that's unlikely to be actionable information to the average shopper.

When you record their sound levels, would you mind also taking a short video recording of the compressor on and off? If you don't have the means to edit them, I'd be happy to if you sent them my way.

Cheers!

 

[67cj5]

That's a reasonable point. Like you experienced, the claims of manufacturers make is one thing, though I hoped to gather real-world data from fridge owners.

Perhaps a recording of each fridge's compressor in environment would be helpful to complement the decibel measurements of each. Heck, even if a company provided a data sheet that documented the pitch, frequency, or resonance of a compressor, that's unlikely to be actionable information to the average shopper.

When you record their sound levels, would you mind also taking a short video recording of the compressor on and off? If you don't have the means to edit them, I'd be happy to if you sent them my way.

Cheers!

Another thing to note is if you take the reading from the oppsite side of where the fan is you will get a much lower reading, if you take the reading from the Fan side your reading will be mainly Wind Noise which is not an accurate reading, Also if you place the fridge with it's back/End within 4 to 8" from a wall the sound will echo up the wall and give a much louder reading, My db meter reads down to around 28.2/28.3 and goes up to over 130/135db. Also turning on the meter and letting it stablize/warm up for 10 or 15 minutes will give a lower reading as dose a lot of test gear.

I will test them all again when I have had a sleep,

 

[Hillbilly Heaven]

Do these fridge use an inverter or frequency switching to control the compressor. If the do then what you are hearing is the switching frequency of the inverter or harmonics from the compressor motor. Shame you can't access the controller and change the programing to avoid these frequencies. Similar to what we do with 3 phase industrial inverters.

 

[klinquist]

Refrigerator: Iceco VL45S Pro
Environment: Inside garage
Average peak measurement with fridge off: 30 dB
Average peak measurement with fridge running: Left side: 45dB, right side 47dB
Fridge off vs. running difference: 15-17dB

 

[plh]

I have an Edgestar 45 and have slept next to it many nights. Its quiet.

BTW @ Klingquist - you have a really quiet garage! I do a lot of sound measurement for work and finding an area outside of a "special room" less than 40 dBA is challenging.

 

[67cj5]

Do these fridge use an inverter or frequency switching to control the compressor. If the do then what you are hearing is the switching frequency of the inverter or harmonics from the compressor motor. Shame you can't access the controller and change the programing to avoid these frequencies. Similar to what we do with 3 phase industrial inverters.

It's caused by the Fan So it's the Wind Speed that is causing the noise,

 

[Shigeta]

Refrigerator: Iceco VL45S Pro
Environment: Inside garage
Average peak measurement with fridge off: 30 dB
Average peak measurement with fridge running: Left side: 45dB, right side 47dB
Fridge off vs. running difference: 15-17dB

Awesome, thanks! Added to the spreadsheet.

I have an Edgestar 45 and have slept next to it many nights. Its quiet.

@plh thanks for chiming in with your experience! In the spirit of the thread, would you be able to take a couple basic measurements as outlined in the original post? In addition to personal stories, comparable empirical data would be super helpful for future fridge shoppers to make reasonable side-by-side comparisons of the sound levels.

 

[Mighty Dodge Ram]

If you have a portable battery box with a cooling fan you might want to add that in also. Just sayin’...

 

[plh]

Awesome, thanks! Added to the spreadsheet.



@plh thanks for chiming in with your experience! In the spirit of the thread, would you be able to take a couple basic measurements as outlined in the original post? In addition to personal stories, comparable empirical data would be super helpful for future fridge shoppers to make reasonable side-by-side comparisons of the sound levels.

No I cannot, the equipment I have access to for measuring sound is lab use only and owned by my employer. I hate to call you out, but your data is not accurate at all. If you are claiming 20dBA running - ha you are joking. Some of the "quietest" Anechoic chambers in the USA have around a 20dBA background noise floor.

 

[Shigeta]

Now is a chance to be part of the solution.

Re-reading the original and subsequent posts might clear a few things up. I'll summarize them here:

1. These measurements can somewhat reasonably be taken without professional lab equipment. I'm not trying to measure to the degree necessary for labs, certifications, or anything formal. My goals are to give fridge shoppers some sense of which fridge is quieter than another.
2. I am not technically-versed in the world of sound, but I'm giving it my best shot since no one else in the community has stepped up to gather this data and nearly all of what I could find was purely anecdotal evidence. (Which, as you probably know, isn't very valuable in comparisons)
3. I stated that if anyone has constructive advice on how to improve this initiative to provide some semblance of empirical data that would serve consumers well, I am more than open to learning how to improve my proposed test method.
   (Note @67cj5's efforts to give advice on how to make tests more accurate and useful to the average consumer)
4. Looking at the spreadsheet of data collected so far, I don't see an entry that claims a 20 decibel level while running. Please correct me if I'm wrong.

I recognize your apparent experience in the field and the last thing I'm trying to do is tout myself as an authority on the subject. I also recognize that my attempts to collect data are very far from perfect.

That being said, in good faith, I'm trying to increase the signal-to-noise ratio of fridge "livability" reviews by collecting this sound level data and I'm asking the community to help.

So far, your posts have generally served to decrease the signal-to-noise ratio by not reading and by contributing in less-than-constructive ways. No one is forcing you to help; if you can't be constructive, at least recluse yourself from the conversation.

 

[Shigeta]

If you have a portable battery box with a cooling fan you might want to add that in also. Just sayin’...

Hey, that's a good point I didn't consider. It's a bit "out of scope" for this comparison of fridges, but it's certainly worth noting when it comes to overall noise while sleeping near a fridge. I'd be happy to share my spreadsheet template if you'd care to start an independent comparison of standalone battery packs.

 

[67cj5]

I have just tested 3 of my fridges, First thing Is my ambient sound levels are between 28.0db and 28.4db.

So Starting with the fridges in order of Compressor Power.

Snomaster 35L "Leisure Series LS35 35L DC. 66 Watt Snomaster.

Front Right = Inlet 28.5db to 28.6db,
Front Left = Fan Side 28.5db to 28.6db

ARB 47L/50Qt, Danfos/Secop DB-35F

Rear Right = Inlet 28.7db to 29.0db,
Rear Left = Fan Exhaust side 35.0 to 40.9db ( Wind Issue )
Rear Back near Fan 28.2 to 28.4db.

Dometic CDF-18L/20Qt ish. Danfos/Secop DB1.4F Micro.

Inlet Right Front of Control on the Side,
28.5 to 28.6db.
Fan to the left of the Control Panel on the side.
28.9 to 29.0db.

Heres the facts the Snomaster 35L has the biggest compressor by far,
Yet it is also the quietest, Most Laptops make more noise than the Snomaster,
Where the sound at 1 metre away or close to 3 feet is about the same as the noise
you hear from breathing out of your Nose, No Fridge beats this one You could sleep with it 4" from your head,
They seem to have really got the Fan Noise under Control. So much so that it is hard to monitor it's on and off cycles
because from 6 to 8 feet away you don't hear it turn on and off and the only way you can tell it's running from that
distance is by the LED Lights.

Next The ARB 47L/50Qt, Although ARB Claim it has a Quoted Noise Level of 50db It is Way Lower,
When you compare the Ambient noise level of 28.0 to 28.4db the ARB is not that loud but for some reason
the Wind from the fan makes it hard to sleep next to, First time I tried it I put Headphones on so I could sleep,
In the Ambient noise levels stated above I can here the ARB from about 10 feet away although it is then whisper quiet,

The Dometic CDF-18L/CF-18 is a pleasure to use, Although the db readings are a fraction more than the Snomaster The Low Tone of the Fan makes it easy to go to sleep in the Van with it under my bed, So much so I had to keep checking it to make sure it was still working As it was stored 12" to the Right of my Head below the 3/4" Ply bed with a 2" Matress, SO it's a Keeper.

Although all these fridges are around the 28/29db mark it is the Frequency/Fan Noise that is the problem, The ARB is a Great Fridge
But the Fan/Rushing Sound is why it comes last out of these 3, Both the CDF-18 and the 35L Snomaster are perfect for use if you have to share the space with a fridge,

Hope that helps.