The noise coming from your refrigerator is almost always produced by the compressor–given that it is one of the few moving parts. But, as we detail ways to quiet compressor noise, you will notice that some of the suggestions deal with other components and issues that serve to amplify sounds, rather than create them.
8 Ways to Quiet a Refrigerator Compressor
Before diving into this, you may want to spend a little time diagnosing where the noise is coming from. A new refrigerator produces between 27 and 45 decibels of sound–most of it from the compressor. Any reading below 40 decibels is considered ‘silent’. It is a good idea to invest in an inexpensive decibel meter to help you understand how much noise you are dealing with.
A decibel level of: 30 is equivalent to a whisper.
40 is the sound of your refrigerator
50 is the sound of moderate rainfall
An older refrigerator is quite likely louder. Maybe a lot louder. One, or some, of the following suggestions could help solve your problem, or at least, quieten things down some.
1) Clean Your Compressor
I would be willing to bet that a large number of people have never cleaned the compressor, compressor compartment, or the cooling fins on the rear of the refrigerator. At least part of the reason for this will be weight and no wheels. Not a lot of fun rocking those old units away from the wall while tearing or scratching the flooring. And, if you are more than 3 decades old, you have tried those loudly advertised appliance moving gadgets like adjustable roller things, slider things, sliding mat things, other things. That did not work. Whatever it takes–just get it away from the wall at least once a year. And vacuum it, dust it, wash it down with a 50/50 vinegar/water mix, and do a little maintenance on it. (Note: Unplug the unit while working on it, and keep any water away from electrical wires and connections.)
Doesn’t hurt to clean the floor and walls also, because the cooling fins create static electricity that attracts dust and dirt that may have accumulated under the fridge or on the walls. (Note: Wiping the fins with lemon Pledge Furniture Polish after they dry will reduce the static somewhat. Do not spray it on. It only requires a light coat.)
Note: When putting the refrigerator back in place, make sure the cooling fins do not touch the wall, or anything else. They will make a high-pitched bad guitar-tuning noise.
The following pictures show our refrigerator. (It is a 15 cubic foot Frigidaire with the freezer on top. About 13 years old. Set into an alcove. Very quiet.)
Refrigerator Compressor in Place
2) Tighten Your Compressor
Stuff happens. The compressor has turned on and off numerous times a day–probably for years. Bolts and nuts can come loose. A little maintenance on the back of your refrigerator does not take much effort. Any more than it does not take much of a loose bolt to cause a vibration or rattle. Pull the refrigerator away from the wall, or out of the alcove. Unplug it. Try to turn any, and all, bolts, screws, nuts you see. If they move, or the part they are securing seems loose, tighten them up. No need for a torque wrench. They just need to be snug to keep things from moving and causing noise, or more wear and tear.
Our compressor (and I suspect most newer refrigerators) does not have bolts or nuts securing it to the base. The 4 compressor legs sit on rubber silencers with a metal piece secured with Cotter ‘R’ Clips. The compressor is attached to the refrigerator base so you will need to make sure the screws holding the base onto the cabinet are tight. Check, and tighten, screws and clamps holding the cooling grid onto the back of the cabinet.
If the rubber feet, or spacers or your compressor seem worn, compressed, or do not exist (because the manufacturer did not use them) you might want to get some. A pack of Rubber Spacer Standoff Washers contains 12 washers–four each of three different thicknesses. It does not take much effort to modify them, if necessary, and install them under the compressor feet. (Note: Depending on the what style of attachments you have, you may need longer bolts.)
3) Level the Refrigerator
Our refrigerator has rollers instead of feet. Only the front two are adjustable. Kind of annoying but works OK. This in not going to be the case if your floor happens to have a dip where one of the feet is going to sit. If the floor is a tad wavy, you could put down a piece of 3/4″ Good One Side (G1S) plywood to at least give yourself a solid base. You could also use laminate or hardwood floor–just for the section under the refrigerator.
Using at least a 2′ level as your guide for level and plumb, adjust the feet, or rollers, as required, if possible. (I prefer to use a 4′ level–because I have one–and it is more accurate.) If you have no adjustment in the feet, you will have to shim them. My choices of shimming material:
- Flat aluminum stock.
- Kitchen counter Formica.
I like these choices because they are about 1/16″ thick (so I am usually not over-shimming), and they are solid, so the weight of the refrigerator will not compress them. Cut whatever you are using into about 3″ squares. (Making them uniform looks better, and they are easier to center under the legs/rollers/wheels.) If you have access to all 4 corners, use a Wonder Bar to raise the the refrigerator and add shims until you get to level and plumb. (This is much easier if the unit is empty.)
Note: Do not use bar under the cabinet part of the refrigerator. The aluminum skin is thin and soft, and the possibility of wrinkling it is high. If you are not sure where your pressure point is, tape a sponge or anti-vibration pad on the bar where it will contact the unit.
If the refrigerator is in an alcove–which likely prevents access to the rear corners–a little creative measuring and math will give you the positions of the rear wheels (or feet). You are going to have to do a little guessing about shim thickness. Once that decision is made, place your shims and screw them to the floor so they stay where you need them. (It is kind of depressing to get the refrigerator exactly where you want it, only to discover that the shims slid to the back of the alcove and you have to start again.)
4) Anti-Vibration Mat or Pads
Once the refrigerator is level, install BXI Anti-Vibration Isolation Pads under each leg or roller. I like these 6″ x 6″ x 2″ thick pads for a few reasons. They work to isolate noise and vibration from the floor. They hold over 400 pounds each so they will not compress. And you can use them for leveling by cutting them down as required. (Most people consider leveling to be the process of raising the complete unit to be level with the highest point. With these pads, you are lowering the refrigerator to be level with the lowest point by cutting down the pads.)
Level, plumb, and square help all appliances to work better, and last longer.
If your refrigerator is in an alcove, the thickness of the pads make placing the unit on them a little challenging. For this application, give some serious consideration to using Exel Neoprene Anti-Vibration Pads. Advantages are that they are only 1/8″ thick and self-adhesive, so it is way easier to get the refrigerator up and onto them, and they will stay where you put them. (Note: If you need extra shimming, screw down your metal or Formica shims first, then stick the Exel Pads on top.)
5) Install Sound Absorbing Acoustics
If there is sound reflection coming off the wall behind your refrigerator, add some sound-absorbing acoustic material. Dekiru Foam will work well to absorb and diffuse sound. Can be attached to the wall with spray glue or double-sided tape. (I would use removable tape.) But really, any type of heavy blanket will do the job. If you have an old quilt, or moving blanket, kicking around, hang it on the wall behind, and on the sides of the refrigerator.
Note: If you think your refrigerator is going to produce too much heat, you might want to use a fire retardant soundproofing blanket. (This is probably a little overkill, but a kitchen fire is no fun.) Whatever you use, make sure you leave at least 2″ of space between the refrigerator and walls, and cabinets above the unit (it you have them). The compressor and cooling fins do produce heat that has to escape somewhere.
6) Soundproof Inside the Refrigerator
Because I have seen this recommended on a couple of other sites, I thought I should also address it. Are you nuts? There is not enough time in my life to glue Mass Loaded Vinyl (MLV) to the inside of my refrigerator. While my wife is explaining to me that she married an idiot. Deservedly so. End of discussion.
7) Surround the Refrigerator With Mass
Build a Refrigerator Alcove
Most compressor noise comes out of the back of the refrigerator because the compressor and cooling fins are located there. One of the best methods of quieting the whole cooling system is to have the refrigerator in an alcove that leaves the front accessible, but surrounds the noise-making parts with walls. Even being able to have one side wall along with the rear wall will be helpful.
Allow at least 2″ of clearance around the unit. More is better, especially if you plan to hang sound absorbing blankets, or any other acoustic panels. (Pyramid-type panels can be up to 2″ thick.) Refrigerator compressors and cooling fins do not produce a lot of heat, but there will be some. Make certain it can escape.
If you are building a wall or two for the refrigerator, use thick, heavy material like 3/4″ MDF or soundproof drywall (QuietRock or Certainteed), or both. More mass is always better. Leave at least 4″ – 6″ head room above. These side walls do not have to be a major construction project. Even if they are only 2′ wide, they will help contain compressor and fin noise. Make them floor to ceiling if at all possible. That way you can use angle brackets to attach them. Quite often, kitchen space is at a premium and and there is not room to build two 2 x 4 walls that end up 4 1/2″ wide each.
Note: I do not know how many times I have heard of someone buying a new refrigerator and having to modify the kitchen cabinets to make it fit. So that is another excellent reason to leave some extra room in your alcove.
If you cannot build an alcove, but do have a little space around the refrigerator, try adding mass around, and above, it with bookcases (for cookbooks, of course), or shelving that will hold towels and any other sound absorbing material.
Sometimes refrigerators sit next to kitchen cabinets which will absorb some of the sound. Quite often there is a gap between upper and lower cabinets that lets sound escape. You might give some consideration to installing a piece of MDF between them to better contain noise. MDF comes unfinished or white from lumber supply stores. Or if you are close to a cabinet outlet, they may have woodgrain MDF that will match your cabinets.
Although I have mentioned this earlier, I will touch on it again. Leave space between the rear wall and cooling fins. Not only do you need room for warm air to escape, but you will also keep it quieter. Occasionally our refrigerator gets pushed too deep into the alcove, allowing the fins to touch the wall. They vibrate, producing some kind of pinging/tapping/singing high-pitched noise. It usually takes us some time to figure out where it is coming from and to pull the refrigerator away from the wall. Makes it go away instantly. (Tends to make me feel inept every time it happens.)
8) Buy a New, Quieter Refrigerator
New refrigerators range in price from around $300.00 to multi-thousands. I am sure that very few people will buy a new one just because of the noise from the old one. (Unless, of course, your unit is producing something akin to birthing noises.) Compressor noise of almost any new fridge should be well under 50 decibels. Although some of the peripheral attachments might be louder–like ice makers. I assume that most manufacturers do not consider noise produced by their units to be a major sales feature because the information is difficult to find.
So, if yours is still keeping things cold, I think your best option is to try some of our soundproofing suggestions.
Miscellaneous Refrigerator Noises
Although not strictly compressor noises, you may hear some of the following sounds, making you wonder what is going on:
- Gurgling – melting ice while the refrigerator is defrosting as water drains into drip tray
- Clattering – ice cubes falling into tray
- Popping/clicking – expansion and contraction of interior walls due to temperature changes
- Dribbling – flow of compressor refrigerant
- Rattling – movement of water lines or cooling fins against the cabinet or trinkets placed on top of the unit
- Primal scream – ice maker quit working
Most of these noises are just common operating sounds of your refrigerator and are usually short duration.
Replace the Compressor
Do It Yourself
If replacing your refrigerator compressor, along with all of the line hook-ups and electrical attachments seems like something you want to attempt, you are braver than I am. Usually I am willing to take a crack at almost anything, but looking at the compressor, and doing a little research about replacing and recharging coolant, and other stuff I do not understand very well, convinced me to leave it alone–if it ever needs to be done.
Note: One of the few good things about getting old is being willing to admit what you do not know, or are not good at.
But if you are going to do the job yourself, make sure you get the correct size and horsepower to match the existing unit with the right number of outlets. Also enough coolant to recharge your system. Not doing it right will probably cost more in the long run.
Consult a Professional
If compressor, or other noises, persist or get louder–especially after you have implemented some, or all, of our suggestions–it might be time to get a professional to have a look at it. Typically, replacement of the compressor will cost between $200.00 and $500.00 depending, of course, on make, model, and quality. You should be able to get a ballpark idea just by talking to an appliance repair company.
The average lifespan of a refrigerator is around 14 years. If yours is getting to that age, you might as well just get a new one rather than replace the compressor. Because all of the other parts on the thing are the same age. Replacing the compressor just to get another year or two out of it–for that kind of money–does not make a lot of sense to me.
Note: Although buying a used one is an option, I would be somewhat hesitant. Unless it is next to free! You can spend 100 bucks on a 7 year old fridge only to need a new compressor 6 months later.
As noted earlier, the average new refrigerator puts out somewhere between 27 and 50 decibels. In the big scheme of things, when compared to other noises you put up with, this is probably not the biggest noise problem in your life. But keep in mind, one noise does not cancel out another. They just pile on. So if I am playing AC/DC at 110 decibels (and trying to turn it up), I will not hear the refrigerator. But that sound is also happening in the house at the same time. Somehow adding to the decibel overload my eardrums are putting up with. As the chart shows, 140 decibels will cause pain. Anything over that, for a length of time, will cause damage.
Yes, I am more than a little anal about unplugging appliances and equipment. And doing electrical work properly. And turning off breakers. I almost lost a co-worker when he grabbed an electrical line that was not powered up (we were told), and a son who ran a sawzall through an electrical line that did not exist in that wall (we were told). God provided you with a full complement of body parts to allow you to function reasonably well. You do not have spare fingers, thumbs, hearts, or brain cells. Unplug the damn thing!
2 thoughts on “How to Quiet a Noisy Refrigerator Compressor”
Great tips. Thank you for creating this webpage!
Glad you liked it.