OK, the fridge is on it’s way to the shop. But in the meantime anyone with a built in fridge might want to check the door fit. Since I built the fridge cabinet myself, I should have known better but just didn’t think of it. Thought the door would have been adjusted properly at the factory. As I mentioned on the last trip my wife really loaded up the fridge for a weeklong boondocking (eastern type) trip. I’ve read other’s post on fridge door’s coming open due to bumpy roads. We’ll CT and NY showed me what they meant. Fridge door opened twice until DW rearranged the food to make the door close better. Seems the latch had a little play that allowed the pin to vibrate up and down with friction causing it to continually catch on the way down until it popped open. That little play in the catch is what caused the gap between the magnetic rubber seal and the fridge face (reads lots of lost cold air). So now that the fridge was out I could see that the bracket that holds the catch is adjustable and of course it was adjusted from the factory to the loosest possible direction for those types that want to slam the door closed and have it latch. Once adjusted, the door closed and sealed properly. Not done yet. The hinge pin that the door rests on also needed adjustment. The rubber magnetic seal was tight all around the door except for 2 inches on both sides of the pin where there was a gap. Once that bracket was adjusted the entire door fit properly. Hopefully, this will decrease the duty cycle and save me some juice. Will still need to add a latch type feature to the bottom of the door to keep it closed for that overstuffed fridge effect!
Picked up the fridge last weekend and the verdict was that I had a quiet fridge “not noisy at all”. Well I picked it up in an empty service bay between two diesel pushers in for repair with a battery was right beside it. Anyway, I got it home and did my own testing in my empty garage, at night, doors closed, and very quiet. The first thing I did was to take off the hard plastic runners on the bottom and I replaced them with rubber feet. I also trimmed the front gill so it didn’t touch the shelf. Better but still had noise. Some of my added insulation (reflectix) around the cooling tubes actually vibrated together when the compressor came on (the adhesive separated). It was surprising how much sound it made. I cut away the insulation from under the edge of the tubes and used metal duct tape to secure the insulation edge. In addition, the cooling tubes form a little cage that surrounds the compressor that generated vibrations that could be dampened by hand. I drilled a little hole in the support bracket that houses the auxiliary fan and tie-wrapped (nylon) the brazed wires on the cage to the bracket that helped to dampen the vibration noise quite a bit. One of the free standing Freon tubes set up a kind of harmonic every once and a while when the compressor was running. Again, I tie-wrapped this to the brazed wires on the cage to add a slight amount of stress that greatly reduced the noise. These fixes helped eliminate induced noise due to vibration from the compressor but of course the sound of the compressor is still audible but is now relatively quiet. Before I reinstall the fridge, I’m going to line the back end of the cabinet with soundproofing material. I think this will help a lot too. I think the fridge is tolerable as is but would think adding sound insulation to the enclosure would make a big difference. Will update again later.
Though I have insulated my Fridge cabinet for sound, I decided to take it another step forward today.
I had taken the fridge out and ran my 12 volt extension to it so I could hear the compressor running while I could look at it.
I too found that some of the coils were vibrating against some wires, sometimes. But I also found there was a noise, vibration induced, coming from the metal skin of the insulated box. Pushing on the compressor eliminated it.
My friend had some self adhesive rubber sheeting, about 3/32 inch thick, with foil on the side opposite the adhesive. I removed the compressor's foot from the back of the fridge, being careful with the copper tubing, and put two layers of this rubber down on the metal skin covering the entire area adjacent to the cooling fins and compressor.. I also put another 2 layers on the compressor's foot itself. This will also act like more insulation to the interior of the fridge, reflecting more heat from the compressor. The screws holding the compressor to the fridge are isolated with some rubber washers and O rings.
After I reattached the compressor to the fridge's box, and turned it on, the vibrations transfered to the fridge itself were cut by about 50%.
I did a couple more modifications to my existing rubber rails and feet, and now none of the compressor vibrations make it to the cabinet itself. Compressor noise is down another 15 to 20%.
When I first installed the fridge 30 months ago, I could tell if the compressor was running by touching the body of the van, and could hear it 10 feet away from the van.
That is no longer possible.
DIT vanner wrote:
"I’m going to line the back end of the cabinet with soundproofing material"
Xcellent Idea.
The way I built my cabinet there is about 8 inches of open space behind the cooling fins. I read somewhere on this forum how there should only be around 1 inch of space between the fins and the back of the cabinet to increase the convective air currents. I think this was more applicable to absorption fridges, but I figured It could not hurt.
I took some 1/2 inch foam board insulation, and applied some sound insulation to both sides of it, and installed it 1 inch behind my cooling fins. I can access this foam panel from the other side of my cabinet, when I pull it away, the sound increases 2 fold, and resonates like a speaker box.
* This post was
edited 11/13/09 05:39pm by landyacht318 *
Great post. I’ll add some rubber sheeting to the fridge box too. Mine didn’t vibrate like yours but I’m sure it will right after I get it back together!
”When I first installed the fridge 30 months ago, I could tell if the compressor was running by touching the body of the van, and could hear it 10 feet away from the van.” Mine was about the same.
”That is no longer possible.” I’ll have to re-test this when I get it back in.
“I took some 1/2 inch foam board insulation, and applied some sound insulation to both sides of it, and installed it 1 inch behind my cooling fins. I can access this foam panel from the other side of my cabinet, when I pull it away, the sound increases 2 fold, and resonates like a speaker box.” This is a great observation on your part. Makes a lot of sense. I was just going to just insulate the boxed-in area but will do that and create the foam panel as well.
Hey, since you seem to be just about done with the fridge mod’s, let me know when you find a fix to mitigate the annoying interruption from the on-off cycle that Booster mentioned in his post Ear plugs don’t count!
A solution to the on/off cycling. leave the door open and turn it up to 5. It should never shut off.
After a night of sleeping next to the unit, it is definitly quieter, and it was cold enough that I had all my white noise fans turned off, except the one inside the fridge, which is barely audible with every other fan turned off.
I wish I could believe I'm done with the refer and cabinet modifications. But I can never leave well enough alone.
I removed the plastic feet that originally came on the fridge, and put 2 layers of 1/2 inch foam on the bottom. It then rests on a floating shelf with ventilation flowing underneath. Yesterday I added a layer of the rubber to the shelf's bottom, and to the top I added a layer of an old type of camping mattress pad. I did lower the rubber bars that the shelf sits upon to account for the extra height, but not enough, so at some point I will remove the fridge again, and perform some possibly unneeded, ineffective noise suppression
I wish I had a lot more of that self adhesive aluminum sided rubber sheeting, I'd line every cabinet surface with it.
I’ll have to look for that kind of rubber sheeting. In the mean time, I’ll contact cement some EPDM rubber that I lined my pond with and cover the other side with Reflectix metal duct tape.
Well guess what! My fridge came out again today. Another round of modifications. Glad I added that quick connector for 12 volts.
I had used some old style foam camping mat on top of the rubber cleats which hold my padded, elevated, fridge shelf. In the days since my last post, this compressed, and once again as more vibrations were transmitted to the cabinet, more noise reverberated.
It was almost as loud as before the previous modification session.
To access the screws on the of the compressor's foot one has to stick a minimum 6 inch phillips screwdriver though the cooling fins. The copper tubing is also in the way.
So I removed the compressor from the fridge again today, and attached 16"x 1/2"x 3/8" inch strips of red oak into compressors foot.
The ends of this red oak are then easily accessible from the top or bottom of the compressor
I placed another layer of the foil backed rubber on the back of the fridge for a total of 3.
This red oak extended foot was then screwed through the rubber into the original sheet metal skin of the fridge, utilizing some more vibration suppression devices.
If I had not previously added 1/2 inch of insulation to the sides of the fridge and extended the verticle rails 1/2 inch as well, I could not have done the redwood foot modification. The cooling fins would be too close to the walls of the cabinet.
Utilizing my staple gun, and plastic zip ties, I got my previously installed noise insulation tighter to the substrate in areas where it had pulled away.
I also have a removable drawer underneath my floating fridge shelf. When the camping mattress on the rubber cleats compressed, the fridge was then resting on this, transmitting vibration right to the floor. Today I removed 3/32 inches from the height of this drawer to eliminate that possibility.
So the result:
The vibrations transmitted to the fridge from the compressor are much less than the last modification and once again vibration is the surrounding cabinet is barely detectable, for now.
A warning. These modifications have been on my mind since the fridge was new. Now that it is out of warranty, I performed the mods. When the compressor foot's screws are removed, the weight of the compressor must be held up in a way to not over stress the copper tubing running to the coldplate. Do not think the copper tubing is strong enough to let the compressor hang from it. I hung mine on a rope from the ceiling.
The copper piping is also in the way of 2 of the screws.
I would not advise removing the compressor with the fridge under warranty. You will void the warranty by doing so.
Not to mention the possibility of cracking a copper tube and rendering inoperable something that didn't need fixing.
Landyacht, chasing vibrations and noise can really be a pain, especially on fragile things like a frig. We are on our (at least) 5th rendition of noise reduction on our bathroom door (07 190P).
Higher frequency vibrations, like the compressor makes, travel though very small paths very readily, so any solid path will do it. Even a very small screw will allow lots of vibration through if it is not totally isolated. Unfortunately, it is very difficult to totally isolate things at home, as it usually requires bonded rubber or special fasteners. I wish I had taken a picture of the compressor on our Isotherm before I put it in, it is mounted on isolation type mounts. It is also on the upper right, rear, of the frig, so it is quite a ways away from the mountings for the frig amd close to the outside openings to let the noise out. Since I did not use isolation mounts on the bottom of our mounting (screws through rubber) and the front is solid mounted, I am hoping the factory isolation is enough for us.
Like you said, the support of the compressor is critical, as copper tubing cracks very easily from repetive flexes, even very small ones. They setup ours so it has all the compressor, condenser, cooling fan, etc all on the flex mounting, so all you have are the two lines to the evaporator, which is in the freezer and fairly far away so the flex is less.
My favorite source for seeing what kind of things are available, for all kinds of projects, is McMaster-Carr. They have pretty much anything and everything. I use them for a lot of the things for my projects at work, as well as at home. They are a wholesale only industrial supplier, so you can't buy direct from them unless you have a home business, or seudo one, or you know someone with a business, but you can see what is available, what it is called, etc, so you can source it elsewhere. Their paper catalog is about 3" thick. Once I retire, I will probably set up an account with them for a minimal business, just so I can still buy from them.
It sounds like the Isotherm is a better built unit.
I love scanning through mcmaster carr, and have bought plenty of speciality screws from them before without a wholesaler's license. I have a couple more ideas using speciality hardware to isolate the redwood from the fridge, but,
I am very happy with the current noise level, but considerable effort was needed.
I'm also thinking of some type of gel padding for the cleat instead of the camping mattress pad which becomes useless in about a week.
I'd like to think that the 3 layers of foil faced rubber reflects the heat of the compressor better, with a corresponding increase in efficiency.
Ear plugs don’t count!
