Reply
 
Thread Tools Display Modes
 
Old 07-11-2012, 09:55 PM   #1
Guru
 
Tom.B's Avatar
 
City: Cary, NC
Country: USA
Vessel Name: Skinny Dippin'
Vessel Model: Navigator 4200 Classic
Join Date: Jul 2009
Posts: 5,154
Idea to quiet fridge

When the compressor of our Not-cold refrigerator kicks on, a low vibration and dull hum encompasses the entire vessel. It's moderately irritating on nights when it's already difficult to sleep.

I have been thinking about the fact that the cabinet it's mounted in are a few large flat boards. I am a sound guy by trade and I just see the cabinet as a giant 3-sided speaker. Also being a car guy, I was wondering if lining the inside of the mounting hole with "hush mat" material will quiet it down.

Anyone see a problem with this? Just thought I would run it by you.

Tom-
Attached Thumbnails
Click image for larger version

Name:	fridge.jpg
Views:	138
Size:	169.7 KB
ID:	11918  
__________________
Advertisement

__________________
2000 Navigator 4200 Classic
(NOT a trawler)
Tom.B is offline   Reply With Quote
Old 07-11-2012, 10:54 PM   #2
Guru
 
Edelweiss's Avatar
 
City: PNW
Country: USA
Vessel Model: 1976 Californian Tricabin LRC
Join Date: May 2011
Posts: 1,834
Hmmm, kind of looks like mine!! My not-so-cold started making a buzzing, vibration sound too. I finally couldn't stand it anymore and took the screws out and pulled it forward out of it's cabinett. The compressor is mounted to the sheetmetal back of the fridg, on a bracket, with some sheet metal screws. It sets up a vibration between the compressor, the lines and fridg. I finally used a couple of strips or rubber inner tube squeezed between the compressor and the fridge to stop the vibration.

There is probably a better way to do this, but it stopped the immediate problem and my head feels better now too.

Larry B
__________________

Edelweiss is offline   Reply With Quote
Old 07-12-2012, 08:18 AM   #3
Senior Member
 
Great Laker's Avatar
 
City: Spring Lake, MI
Country: USA
Vessel Name: Great Laker
Vessel Model: American Tug 34
Join Date: Jan 2011
Posts: 321
Noise is transmitted through the air and conducted throughout the boat through the refers attachment to the boats structure. For the best result, you will need to address both sources of noise.

As you indicated, absorbing material in the cabinet surrounding the refer will help attenuate the directly radiated sound which is being focused by the cabinet out into the interior of the boat. Common house insulation will work. Be sure not to block the necessary air flow needed for cooling the compressor.

The vibrations can be attenuated by physically isolating the refer from the cabinet/floor. One simple and inexpensive way is to place it on 2 in sq cork/rubber pads such are commonly used under furnaces and air conditioners. If possible avoid or minimize directly fastening or bolting the refer to the structure around it.
Attached Images
 
__________________
Larry
American Tug 34 - Great Laker, and Gold Looper
Home port on the vast unsalted Lake Michigan
adventuresofgreatlaker.blogspot.com
Great Laker is offline   Reply With Quote
Old 07-12-2012, 08:32 AM   #4
Guru
 
City: North Charleston, SC
Country: USA
Join Date: Sep 2010
Posts: 4,390
As Great Laker posted, you have two sources of sound radiation and need to deal with each in a different way. Ther refrigerator's compressor should be isolated from its mounting surface if possible. The pads he shows seem like a good way to do this. If possible, do not have mechanical fasteners connecting the compressor to the mounting surface. For a horizontal mounting, adhesive might serve to mount the compressor to the pad and the pad to the boat or refrigerator case. You can see what you have so you will be able to determine what will work and what will not.

As for the sound radiated by the wooden panels, it may not be an issue once the compressor is isolated. If the panels still radiate sound, I think something like auto undercoating would work better than fiberglass or foam rubber. This will serve to deaden any resonation or vibration. If you search on the Internet, you should find a coating specifically made for deadening sound. This would be the best plan.
rwidman is offline   Reply With Quote
Old 07-12-2012, 09:11 AM   #5
Guru
 
Tom.B's Avatar
 
City: Cary, NC
Country: USA
Vessel Name: Skinny Dippin'
Vessel Model: Navigator 4200 Classic
Join Date: Jul 2009
Posts: 5,154
Good ideas. I'll take a look at the compressor mounting when I pull it out.

The only downside I see to those blocks, Larry, is that it might lift the fridge up to the point that it won't fit in the hole anymore. Where can I shop for them? Maybe they have thinner options.

Ron, here is the kind of stuff I am looking at:

https://www.google.com/search?q=auto...w=1680&bih=948
__________________
2000 Navigator 4200 Classic
(NOT a trawler)
Tom.B is offline   Reply With Quote
Old 07-12-2012, 09:13 AM   #6
Senior Member
 
Great Laker's Avatar
 
City: Spring Lake, MI
Country: USA
Vessel Name: Great Laker
Vessel Model: American Tug 34
Join Date: Jan 2011
Posts: 321
There are also two things going on with the side walls.

One is that the side panels can reflect sound out into the cabin like a speaker cabinet. Because of the various wavelengths involved, the best approach to attenuate these reflections is a porous absorbing material with some appreciable thickness. If there is room and air flow permits, a few inches of insulation is best.

The other is that the side panels can also start vibrating and transmit that energy throughout the structure of the boat where it vibrates other panels which act as speakers to recreate the sound elsewhere. If this is happening, the best approach is to strengthen and add mass to the side wall. There are products specially designed for this and as has been pointed out, auto undercoat might be an inexpensive substitute.

These products combine both absorption and mass to reduce noise. A common application is noise from an engine compartment in a car or boat. They can be glued or stapled on the side panel. Dynamat is an example but there are many and you should look around for something simple and inexpensive. Try Google and your local auto stores.
__________________
Larry
American Tug 34 - Great Laker, and Gold Looper
Home port on the vast unsalted Lake Michigan
adventuresofgreatlaker.blogspot.com
Great Laker is offline   Reply With Quote
Old 07-12-2012, 09:25 AM   #7
Senior Member
 
Great Laker's Avatar
 
City: Spring Lake, MI
Country: USA
Vessel Name: Great Laker
Vessel Model: American Tug 34
Join Date: Jan 2011
Posts: 321
Tom,

Here is an example rubber/cork pad and one source. Very inexpensive. You might find them at a local home improvement store as well. High end stereo dealers also sometimes stock them for audiophiles.

MP-2C - DiversiTech MP-2C - Rubber/Cork Anti-Vibration Pad, 2" x 2" x 7/8"
__________________
Larry
American Tug 34 - Great Laker, and Gold Looper
Home port on the vast unsalted Lake Michigan
adventuresofgreatlaker.blogspot.com
Great Laker is offline   Reply With Quote
Old 07-12-2012, 02:05 PM   #8
TF Site Team
 
Pineapple Girl's Avatar
 
City: San Mateo, CA
Country: USA
Vessel Name: Pineapple Girl II
Vessel Model: PT 35
Join Date: Jun 2010
Posts: 2,165
This is some great advice, thanks for asking this question Tom.

I had guests in my V berth complain about the reefer noise keeping them up all night so I had the refrigeration guy check the fridge while he was out doing a warranty repair on my ice maker. He said that is just how these units are and I should go ahead and pick out my replacement fridge now so I would be ready to go with it when the not cold dies, as it inevitably (according to him) will. Great, one more thing to budget for. gotta love this yachting stuff. Meanwhile I will take a look at the space I have for some of these sound dampening ideas!
__________________
-Jennifer
Pineapple Girl II 1984 PT 35
San Francisco Bay Area
www.pineapple-girl.blogspot.com
Pineapple Girl is offline   Reply With Quote
Old 07-12-2012, 02:45 PM   #9
Senior Member
 
Great Laker's Avatar
 
City: Spring Lake, MI
Country: USA
Vessel Name: Great Laker
Vessel Model: American Tug 34
Join Date: Jan 2011
Posts: 321
Since we are tossing around refer sound reduction ideas, here are a couple more.

While the cooling fans come on and off based on temperature, they run at full speed when on and can be quite loud. If you boat in cooler climates or have not had any trouble keeping the refer cold, look at the location of the fan. If it is close to an external ventilation grid the noise will be easily heard. You might be able to relocate it to the other side of the refer where it would be quieter. In either case, it should be positioned to direct the air across the coils.

Also, again assuming you have not had any difficulties keeping the refer cold, you can put a small potentiometer in series with the fan negative wire and use it to reduce the speed of the fan. The fan will run a bit longer each time but be quieter since the blade and vibration noises are reduced. The resistance of the pot should be about the same as the effective resistance of the fan itself so it can reduce the current up to 50% of the rated value. Many fans will not self start below this amount anyway. Mount the pot in an accessible location and you can play with the speed depending on how much cooling is needed.

Thinking in reverse, if you boat in hot climates and have cooling problems, you can mount an additional fan with a pot in the refer compartment to assist in cooling and adjust it as required. One good location is to have it near the top exhausting warm air out of the case. In this case it is better to have some additional noise than have warm beer! Use a small fan of the type found in desktop computer cases. These are very inexpensive and very quiet. Electronics surplus stores have them in piles for a couple of $ each.

If you are not comfortable with electrical work or calculating the resistance needed, find someone who is. It is fairly simple.
__________________
Larry
American Tug 34 - Great Laker, and Gold Looper
Home port on the vast unsalted Lake Michigan
adventuresofgreatlaker.blogspot.com
Great Laker is offline   Reply With Quote
Old 07-12-2012, 03:21 PM   #10
Guru
 
City: North Charleston, SC
Country: USA
Join Date: Sep 2010
Posts: 4,390
Quote:
Originally Posted by Pineapple Girl View Post
I had guests in my V berth complain about the reefer noise keeping them up all night so I had the refrigeration guy check the fridge while he was out doing a warranty repair on my ice maker. He said that is just how these units are and I should go ahead and pick out my replacement fridge now so I would be ready to go with it when the not cold dies, as it inevitably (according to him) will.
If I was paying a service person and he blew me off with that sort of answer to a serious question, I would not be using that service person in the future.

First, any piece of mechanical equipment will eventually fail. If they didn't this guy would not have a career. Picking out a replacement for your refrigerator now would be pretty stupid because it may be ten years from now when you eventually need a replacement and manufacturers and models come and go. Prices change, dealers change, and technology changes.

Second, as you can see here, anyone who is willing to stop his mindless chatter and actually look into the problem will find (as we see here) that there are several ways to eliminate or at least reduce noise and vibration from mechanical systems.
rwidman is offline   Reply With Quote
Old 07-13-2012, 04:31 PM   #11
TF Site Team
 
Pineapple Girl's Avatar
 
City: San Mateo, CA
Country: USA
Vessel Name: Pineapple Girl II
Vessel Model: PT 35
Join Date: Jun 2010
Posts: 2,165
Quote:
Originally Posted by rwidman View Post
If I was paying a service person and he blew me off with that sort of answer to a serious question, I would not be using that service person in the future.

First, any piece of mechanical equipment will eventually fail. If they didn't this guy would not have a career. Picking out a replacement for your refrigerator now would be pretty stupid because it may be ten years from now when you eventually need a replacement and manufacturers and models come and go. Prices change, dealers change, and technology changes.

Second, as you can see here, anyone who is willing to stop his mindless chatter and actually look into the problem will find (as we see here) that there are several ways to eliminate or at least reduce noise and vibration from mechanical systems.
LOL well he was visiting on a warranty call so no money was involved. The refrigerator is going to fail at ANY MOMENT, thus I need the replacement picked out NOW. I want a new fridge anyway for energy efficiency reasons (since we like to anchor out a fair bit) so I will prob replace before next summer. Maybe. Probably. Maybe.

We shall see! Meanwhile I think I shall try out some of these great ideas to at least make the current unit a little quieter.
__________________
-Jennifer
Pineapple Girl II 1984 PT 35
San Francisco Bay Area
www.pineapple-girl.blogspot.com
Pineapple Girl is offline   Reply With Quote
Old 07-13-2012, 04:57 PM   #12
Guru
 
Dougcole's Avatar
 
City: Carrabelle, FL
Country: USA
Vessel Name: Morgan
Vessel Model: '05 Mainship 40T
Join Date: Jan 2008
Posts: 800
It's funny, and I am likely jinxing myself here, but everyone rips on Norcold. I've had that same fridge now for 8 years (I bought it new) of hard use without a hitch. Early in a long Bahamas trip we absolutley CRAM it full....you couldn't slide a hot dog into the freezer. In the meantime my brother's higher end fridge, ice maker and freezer in his Ocean have all failed at least once.

No sound issues with mine either, you can hear, but heck, you can hear my home fridge too if you are standing in the kitchen.

I guess it is just one of those things, some good units, some not so good.
Dougcole is offline   Reply With Quote
Old 07-13-2012, 05:42 PM   #13
Guru
 
City: North Charleston, SC
Country: USA
Join Date: Sep 2010
Posts: 4,390
Quote:
Originally Posted by Pineapple Girl View Post
LOL well he was visiting on a warranty call so no money was involved. The refrigerator is going to fail at ANY MOMENT, thus I need the replacement picked out NOW. .............
Often, these things can be repaired at reasonable cost. I'm thinking the repair person was making a comment about the brand of refrigerator. And I wouldn't call him for anything I was paying for, especially if your refrigerator needs service.

Anytime someone "badmouths" a product, he or she is a person to be wary of.
rwidman is offline   Reply With Quote
Old 07-13-2012, 06:38 PM   #14
Guru
 
psneeld's Avatar
 
City: Avalon, NJ
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 15,924
Quote:
Originally Posted by Dougcole View Post
It's funny, and I am likely jinxing myself here, but everyone rips on Norcold. I've had that same fridge now for 8 years (I bought it new) of hard use without a hitch. Early in a long Bahamas trip we absolutley CRAM it full....you couldn't slide a hot dog into the freezer. In the meantime my brother's higher end fridge, ice maker and freezer in his Ocean have all failed at least once.

No sound issues with mine either, you can hear, but heck, you can hear my home fridge too if you are standing in the kitchen.

I guess it is just one of those things, some good units, some not so good.
Bingo...have had nothing but good performancefrom Norcold on several boats and an RV.

There are techs that don't like certain brand anything/everything and that's their experience and perogative...doesn't make them bad techs...just opinionated like the rest of us!
psneeld is offline   Reply With Quote
Old 07-13-2012, 09:54 PM   #15
Guru
 
City: Hotel, CA
Country: Fried
Join Date: Sep 2011
Posts: 8,328
Quote:
Originally Posted by Dougcole
It's funny, and I am likely jinxing myself here, but everyone rips on Norcold. I've had that same fridge now for 8 years (I bought it new) of hard use without a hitch. Early in a long Bahamas trip we absolutley CRAM it full....you couldn't slide a hot dog into the freezer. In the meantime my brother's higher end fridge, ice maker and freezer in his Ocean have all failed at least once.

No sound issues with mine either, you can hear, but heck, you can hear my home fridge too if you are standing in the kitchen.

I guess it is just one of those things, some good units, some not so good.
What's funny to me is this forum has been the only place I've ever heard a negative remark about Norcold. I share your an Mr psneelds experience.

6 RV's and most of my friends and families RV's never a single failure in over 20 years. Dometic is the other brand we've had equally good luck with.

We are all the product of personal experience. I'd buy either one of those brands without giving them a second thought.
__________________
Craig

It's easier to fool people than to convince them that they've been fooled - Mark Twain
CPseudonym is offline   Reply With Quote
Old 07-14-2012, 01:29 AM   #16
Guru
 
Edelweiss's Avatar
 
City: PNW
Country: USA
Vessel Model: 1976 Californian Tricabin LRC
Join Date: May 2011
Posts: 1,834
Quote:
Originally Posted by Dougcole View Post
It's funny, and I am likely jinxing myself here, but everyone rips on Norcold. I've had that same fridge now for 8 years (I bought it new) of hard use without a hitch. Early in a long Bahamas trip we absolutley CRAM it full....you couldn't slide a hot dog into the freezer. In the meantime my brother's higher end fridge, ice maker and freezer in his Ocean have all failed at least once.

No sound issues with mine either, you can hear, but heck, you can hear my home fridge too if you are standing in the kitchen.

I guess it is just one of those things, some good units, some not so good.
-------------------------------------
Actually the Norcold fridges have been very reliable and dependable. I have owned three of them now, and they usually last 20+ years. The reason I call mine Not-So-Cold has more to do with their inability to keep ice cream below it's freezing point. While all three of mine would freeze water and most other liquids, none of them could keep ice cream solid for more than a day.

AND I REALLY. . . .REALLY. . . LIKE. . . Ice. . Cream!!

(And that is my story and I'm sticking too it.)

LB
Edelweiss is offline   Reply With Quote
Old 07-14-2012, 07:48 AM   #17
Guru
 
Tom.B's Avatar
 
City: Cary, NC
Country: USA
Vessel Name: Skinny Dippin'
Vessel Model: Navigator 4200 Classic
Join Date: Jul 2009
Posts: 5,154
Same here... I am ok with it, BUT it really just doesn't keep stuff THAT cold. The biggest issue is that the cooling system seems too small and takes FOREVER to recover from just a door opening. It also builds up ice on the coils quickly. As a cold box, it's fine. As a cold box that has a door that needs opening alot... It's not that good.

Tom-
__________________
2000 Navigator 4200 Classic
(NOT a trawler)
Tom.B is offline   Reply With Quote
Old 07-14-2012, 09:51 AM   #18
Senior Member
 
honeybadger's Avatar
 
City: Hampstead,NC
Country: USA
Vessel Name: HoneyBadger
Vessel Model: 1990 Harkers Island Trawler Typical wooden hull with a Carolina flare and no deadrise at the stern
Join Date: May 2012
Posts: 194
Yoga mat ! it is about 1.5 inches thick and i used a hole saw to cut some round washer backers, Then the face mounting is also backed with a layer of Yoga mat. Made a big difference.
honeybadger is offline   Reply With Quote
Old 07-14-2012, 10:11 AM   #19
Guru
 
City: North Charleston, SC
Country: USA
Join Date: Sep 2010
Posts: 4,390
Quote:
Originally Posted by CPseudonym View Post
What's funny to me is this forum has been the only place I've ever heard a negative remark about Norcold. I share your an Mr psneelds experience.

6 RV's and most of my friends and families RV's never a single failure in over 20 years. Dometic is the other brand we've had equally good luck with.

We are all the product of personal experience. I'd buy either one of those brands without giving them a second thought.
I see negative comments about Norcold refrigerators all the time on boating forums, but I think it's a lot like the Bayliner comments. There are so many out there that there are bound to be some problems. Most people complain if they don't like a product, but say noting if they are satisfied with it.

A wise and competent repair person will never "bash" a product, at least publicly. He (or she) will just try to repair it and satisfy the customer.
rwidman is offline   Reply With Quote
Old 07-15-2012, 08:49 AM   #20
Senior Member
 
Lobstah's Avatar
 
City: Dunedin, Fl
Country: USA
Vessel Name: T/T Whistful
Vessel Model: Boat US 12' Inflatable
Join Date: Jul 2011
Posts: 220
Quote:
Originally Posted by rwidman View Post
I see negative comments about Norcold refrigerators all the time on boating forums, but I think it's a lot like the Bayliner comments. There are so many out there that there are bound to be some problems. Most people complain if they don't like a product, but say noting if they are satisfied with it.

A wise and competent repair person will never "bash" a product, at least publicly. He (or she) will just try to repair it and satisfy the customer.
There have recently been a rash of RV fires caused by NorColds. There was a recall, I believe, to address a certain issue with them. I have a Dometic in the RV, and have had 2 issues in 4yrs. One was a circuit board failure ($129) and the other more recent one was a blown fuse.

**edit**
Upon doing a google search, it also appears that there are some instances of Dometic fires in RVs as well.

Jim
__________________

Lobstah is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 08:37 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012