Blown Foam Insulation

[Bones]

I'm rehabbing a WH-12T chest cooler and am thinking about replacing the fiberglass insulation with a more efficient closed cell spray foam insulation. I'm wondering if anyone has done this before and if they could recommend a product. Having worked with "Great Stuff" and other products like it, I know the stuff can be difficult to work with, particularly if I'm trying to fill a cavity between the liner and the body of the cooler. I'd prefer to line the area to be filled with thin plastic sheets so as not to lock the entire unit solid with the foam. I've seen some products for use in construction applications, but fear it would be difficult and messy to try to shoot the product into the thin space I'm trying to fill.

Any thoughts, comments, or recommendations appreciated.

[coke_and_stuff]

I personally would not do this, If you ever had to break that liner out again you wouldnt be able to, also you could actually stress the outside metal on the cabinet and cause it to bend out.

Joey

[Bones]

Yeah, I agree on wanting to preserve the ability to get the liner out at a later date. That is why I would want to line the foamed area with plastic, so as not to glue the whole thing solid. I thought about filling a large garbage can bag, a very thin one, with the foam while positioned between the liner and cabinet. Then the foam would expand to fill the space, but would be contained within the bag. This way, there would be no adhesion to the cabinet or the liner. I could still slide the liner out as it would have the bag between it and the foam. That's the theory anyway. It may be difficult to do.

[collecture]

How would you get insulation under the liner? I'd stick with traditional fiberglass. If you want to spend the bucks, you could put rock wool in there.  

[Bones]

For under the liner I was thinking about the extruded polystyrene board (the pink board or something similar that you can get at Home Depot). There were styrofoam pieces under the liner to support it and prevent the fiberglass from being crushed. It is about 2 1/4 inches thick. So if I had that for a base, I was thinking of shooting each of the four sides separately within the bags I described above. If the bags are thin enough, like most of the cheaper garbage can liners, the foam should have no problem expanding to fill the cavity. I don't think the expansion would be anywhere near enough to bend the cabinet metal walls. Any over fill would likely come out the top along the edge of where the liner and cabinet come together. This area should easily be trimmed after the foam cures. I do worry about voids in the area I'm trying to insulate if I don't get the material deep enough and the foam doesn't expand to the degree necessary to completely fill the area. If my method works, I could remove the liner after the foam cures and check for voids. But if I screw it up, I'll have one hell of a mess.

Sounds like no one is aware of anyone doing this. I'll continue to monitor for other thoughts.

Thanks for your questions and suggestions.

[Bones]

Check out the video under "Slow Rise Closed Cavity Video" on this site. This is one of a few different products I've found. Don't know if its the best option, but it gives you an idea of what I'm thinking of.


Slow Rise Closed Cavity Video

It doesn't look that difficult.

[Creighton]

First off welcome to the board! Unless that machine is going to be in some extreme weather conditions I see no value in injected foam.  Normal insulation should be fine with no headaches down the road.
Just my thoughts...
Creighton

[loman4ec]

I agree with creighton. I replace the insulation in all of the machines I build and I always use regular insulation. I have never had a problem. It is also cheep and easy to install.

[sodaworks]

I concur!!

[Bones]

Thanks for all the great feedback, its appreciated.

It seems that all agree that fiberglass works fine. But I can't help but think that you don't see fiberglass in new refrigerators or freezers these days, its all foam injected. I suppose it comes down to a cost/benefit analysis. The foam is more expensive than fiberglass for sure, but it also has an R-value twice as high as fiberglass. Blown in place foam is R-6.25 per inch, while fiberglass is only 3.14 per inch, so in theory, my compressor will run half as much if I use foam as compared to fiberglass. Ease of installation would also be a factor. Foam would be much more difficult to install. I also like the idea of the closed cell characteristics of the foam, which would not lose its insulating characteristics if it becomes wet. I keep my cooler in the garage, and on hot & humid summer days I worry about condensation. When I disassembled the unit, I did detect areas where condensation occured. I suppose if I make sure the cabinet and liner are well sealed, I can avoid that.

Thanks again for all the thoughtful comments.