Re-insulating My Refrig. Box the Hard Way.

[patprice]

Hmmm. My fridge is also sub standard and used in Greece, read HOT. I,Lleyton start planning an upgrade.

[john61ct]

Foil-bubble, AKA Reflectix has near zero insulating value.

It is a radiant barrier only, to be installed behind an air gap outside all insulation, pointing out. Helps prevent the hot sun from penetrating, basically like an awning.

Otherwise useless, waste of space.

Polyiso is the best Rvalue per inch for foam, although a 1/2" of something else facing the interior is helpful.

[skipgundlach]

Originally Posted by john61ct

Foil-bubble, AKA Reflectix has near zero insulating value.

It is a radiant barrier only, to be installed behind an air gap outside all insulation, pointing out. Helps prevent the hot sun from penetrating, basically like an awning.

Otherwise useless, waste of space.

Polyiso is the best Rvalue per inch for foam, although a 1/2" of something else facing the interior is helpful.

True, but has to be totally encased, as it's hydroscopic -which is a very bad thing for insulation...

[AKA-None]

My P.O. drilled holes in the box and shot foam in. Guess he forgot about gravity as I’ve been digging foam out of everything including under the oil pan. Sheesh

[SVTatia]

Originally Posted by jhulmer

...
Stay tuned for more tomorrow:

This is great - lots of learning - keep on posting jhulmer, thanks...
I am sure John Coldeh, Richard K and Rich are lurking... they are great and the best in the business

Originally Posted by AKA-None

My P.O. drilled holes in the box and shot foam in. Guess he forgot about gravity as I’ve been digging foam out of everything including under the oil pan. Sheesh

[john61ct]

Originally Posted by skipgundlach

True, but has to be totally encased, as it's hydroscopic -which is a very bad thing for insulation...

Well it is what the pro's use, obviously just need to do it right, not talking about just sticking slabs in with your food.

[OzePete]

Not sure, but looking at your pictures it may be possible to remove the upper stainless steel entry surround. This may make it easier to re-insulate with blue board as John (and we) recommended, vapour seal then reline the interior with say 6mm thickness ABS plastic or a similar non conductive material.

If you can remove the stainless steel entry surrounds I would suggest replacing with a non conductive material. Metal from the outside world to the interior of a cabinet will increase heat penetration greatly and contributes to moisture saturation of insulation in the long term.

Cheers, OzePete Ozefridge | 12 Volt Refrigeration Systems

[Billnpr]

Spray foam will absorb water from any source.

[jhulmer]

Originally Posted by OzePete

Not sure, but looking at your pictures it may be possible to remove the upper stainless steel entry surround. This may make it easier to re-insulate with blue board as John (and we) recommended, vapour seal then reline the interior with say 6mm thickness ABS plastic or a similar non conductive material.

If you can remove the stainless steel entry surrounds I would suggest replacing with a non conductive material. Metal from the outside world to the interior of a cabinet will increase heat penetration greatly and contributes to moisture saturation of insulation in the long term.

Cheers, OzePete Ozefridge | 12 Volt Refrigeration Systems

OzePete it would have been much easier to do this project if I could remove the countertop. But, it was glued down and I didn't want to risk damaging it. It has proved to be a very nice addition to the galley.

I am aware of the thermal bridge formed by the metal and have made some adjustments to my doors to minimize its effect. I will reveal as I progress.

Thanks for your suggestions,
Jim

[jhulmer]

PROJECT POST: #3

I started to formulate a plan to control the pour-in-place foam. If you haven't worked with this stuff it can teach you new curse words! It will make you invent new curse words.

My first exposure to this magical invention was in college when I work in the flight research lab. They bought it in 55gal drums and left unattended was a catalyst for trouble. But, that's another story. We used it mainly to make molds and fill voids in test models. The "experts" with lots of experience still struggled with it from time to time. So the key is to make it go where you want and if not give it a planned escape route of your choice.

I dug out all of the old foam in the first quadrant that I cutout. I also, dug out as much as I could behind the walls of the liner still in place. My goal here was to create the first chamber to pour foam into that would setup side forms for the next chambers.

I dug out some of the old foam in the second quadrant but I left a wall of old foam dividing the two open quadrants. Digging out the top of that wall gave me room to pour foam in the first section.

This foam sticks to almost EVERYTHING! However, it doesn't stick, very well, to clear poly sheet plastic. So I lined everything that foam could come in contact with plastic sheet. This is plan B, in case the foam doesn't listen to where you tell it to go.

Additionally, I lined the inside and outside of the first section of the liner with plastic. This would allow me to remove this section after the foam cured. Which would give me access to the other areas to pour foam. Note that the first section has the 1-1/2" hole for the refrigeration line set, this is in the plan to finish the pour later.

I then lined the void to be foam filled with 6 mil clear poly sheet to form a moisture barrier outside the foam and to keep the foam from going to the bilge as a liquid. Understand, when the foam expands it can move things, big things! SO you have to give it an easy escape. It really wants to play nice it just doesn't know how. Make sure that the liquid can't run were it doesn't belong. I taped the plastic seems up with vinyl barrier tape used for vapor barriers and air duct applications. I used good masking tape to hold the plastic in place. Allow the plastic sheet to cover the existing old foam boarders that I left to create a form. The plan is to dig out the old foam and use this plastic to tape to the rest of the outside plastic barrier in the other sections.

The next step was to put the liner section back in place in the 1st quadrant and secure it in place with wood blocks screwed to the adjacent sections. More is better here to prevent bulging of the seem. You will notice, as we go on, I added more to the other sections and I probably should have add a few more still. But, this worked out ok.

I will continue tomorrow with how I poured the 1st section.
thanks for following,
Jim

[jhulmer]

PROJECT POST: #4

POURING THE FOAM.

I used a two-part pour in place 3 pounds per cubic foot polyurethane foam.

http://www.morrismaterials.com/

I think most builders use a 2 lbs/cuft density but I prefer the denser foam. From what I can find both provide between R-5 & R-6 of insulation per 1 inch of thickness.

It will take more of the 3 lbs/cuft then the 2 lbs/cuft to fill the same space. In other words the 2 lbs/cuft expands more for the same amount of liquid mix.

As I mentioned I have the first quadrant ready to pour. My goal here is not to fill the void to the top, but to fill it at least halfway. My reason is that after it cures I can remove all the other old foam and setup to pour the other areas by passing the cups of liquid over the top of this first pour. This will provide a blocking dam to keep the foam expanding in the voids not out of this hole.

Now I have my barrier plastic taped in place and the liner section I cutout lined in plastic to prevent the foam sticking. I have inserted the section back in place and screwed wooden blocks up and down these seams to prevent the foam from pushing it out. In this pour the foam has room to expand so not to worried about bulging. However, It still did a little because I didn't worry about. I should have add a few more blocks, which I do later.

Here are my tricks to mixing and pouring this foam:

• Wear protective clothing and good nitrile gloves, eye protect, carbon respirator. Keep acetone ready for cleanup before it cures. After it cures it is very difficult to cleanup.
• Keep the liquid foam at or a little below 70 deg F - slows its reaction time and gives a more uniform cure. You can put it in the refrigerator for a little while (if your significant other isn't home) but don't let it get below 69 deg f.
• Mix in small batches, one quart at a time. This will give you time to mix properly before it reacts.
• Mix it for a full 20 to 30 seconds before you pour. Scraping the sides and bottom well. This also gives you a much better reaction and cure. You don't want gooey unmixed liquid on the surface of the foam.
• If working alone Wait about 10 to 15 minutes between pours to avoid heat buildup.
• If you have help you can use a team effort of mix and pour up to about 5 quarts in this application. But be very quick about it, its better to pour in to different adjoining areas then to pour on top of the same spot each time.

This first pour I worked alone and mixed and poured about 3 qrts in roughly 30 mins. I waited until the next day to remove the liner section. The foam will cure hard to the touch in about 10 mins and fully cure in about 12 hours. Its best to let it cool and cure before messing with it too much. However, for molds and such we worked it after about 15 mins because it is softer.

After this initial pour it was time to remove all the other liner sections and clean out all the old foam.

I will continue tomorrow with replacing the bottom board and lining with moisture barrier plastic and making the next pour.

Thanks for following and I hope this helps someone with their own project,
Jim

[RickG]

Originally Posted by john61ct

Foil-bubble, AKA Reflectix has near zero insulating value.

It is a radiant barrier only, to be installed behind an air gap outside all insulation, pointing out. Helps prevent the hot sun from penetrating, basically like an awning.

Otherwise useless, waste of space.

Polyiso is the best Rvalue per inch for foam, although a 1/2" of something else facing the interior is helpful.

Understood, but I have three relatively air-tight layers taped with aluminum tape with some air gap between layers. Real world results over four months show that it works. Adding an internal layer of Polyiso or similar would be a good next step. Amvic sells an R10 high density EPS concrete backer product that only has 1.5% water absorption; putting a layer of Reflectix around a 2" sheet of the Amvic product. Time for more experiments when my other 11 projects are complete.

jhulmer, thanks for the details. I am intrigued with approach and look forward to the final report!

Cheers, RickG

[Pete7]

Originally Posted by john61ct

Foil-bubble, AKA Reflectix has near zero insulating value.

It is a radiant barrier only, to be installed behind an air gap outside all insulation, pointing out. Helps prevent the hot sun from penetrating, basically like an awning.

Otherwise useless, waste of space.

Whilst no applicable in this instance, surely using it on the outside of the box were access is available then it would be worth while to keep radiated heat out of the fridge box?

[john61ct]

Yes, just draping it over the cooler, mylar side facing the sun to create shade is helpful.

[jhulmer]

PROJECT POST: #5

After the first pour to create a dam that will give me control over the next big pour, I cut out all the remaining liner panels and removed all the old foam.

The bottom of the outer box that was built by the factory was also thin plywood that was delaminating and had to be replaced. What I decided to use was fiberglass wall panels from the local building supply store. I cut out all the old thin plywood, leaving the fiberglass corners that were tabbed in place by the factory. I cut the frp wall board to fit and located and drilled a hole for the drain pipe to pass through. I then used thickened epoxy to glue the bottom in place to create the outer form for the foam.

Next I lined the whole cavity with 6mil poly plastic and taped it together with mylar duct tape. As well, I secured the poly liner from the first pour to the new liner. This will contain the liquid foam when making the pour and it will form a moisture barrier on the outside of the foam after it cures.

I installed the drain pipe through the liner and bottom plate and added the hose fitting to help support the bottom from bulging.

You can see that I have covered all the liner sections with poly plastic to make cleanup much easier after pouring all the foam. I also, left the inner poly lining on the first quadrant I poured, because I will be putting this section on and off as I finish pouring foam.

I then replaced all the liner panels, except the first one, back in place and secured them with plywood blocks and screws. I measured and placed the screw holes within a two inch wide strip along the seam of each cutout. This area will be covered by two inch fiberglass cloth tape that will seal the seam. I added more blocks then before, but probably could have added more. The strips of plywood worked well, but prevented the monitoring of the rise of the foam through the seams.

Here is where you need a helping hand. This the biggest pour I made and I hoped it would be enough to fill most of the cavity.


The formula provided for figuring the expansion of the foam you choose is:

Your formula for finished product is measured in cubic feet and is figured by the lbs of the material divided by density of the foam.

2 lb foam is 9.5/2 = 4.75 cubic feet

3 lb foam is 9.5/3 = 3.16 cubic feet.

You can also do a test by mix a small amount of the foam in a quart measuring cup and see what the expansion is after the foam cures. This method works for me and it's different for every foam.

I calculated that I was going to need a total of 4 gals of foam, two 2gal kits. This was a Wild guess at the volume of the box and as it turned out fairly accurate. I get lucky every once in a while.

This pour was going to be just enough, hopefully, to fill the whole bottom of the void. With the help of a friend, I poured five quart mixing cups with 16 oz of Part B (it is the thickest). We started by mixing the first and then the race was on. Mix vigorously for 20 seconds then pour into the bottom of the void by passing the cup through the gap formed by the original pour and the installed liners. At the same time your helper is pouring and mixing the next quart and so on. I poured one quart to the left and then the next quart to the right. I reinstalled the open liner section and waited. you can follow the foams expansion by watching the seams and by feel. The heat transfers through the liner and your can tell where the foam is touching it.

This five quarts did a nice job of filling the bottom of the box and up the walls a little bit. I let this cure and cool. It did produce fair amount of heat but was not excessive.

The next day I continued by mixing three more quarts and pouring as far back into the void as I could reach the cup. But this didn't fill some of the void on the opposite side of the opening I was using. You can see where I marked the top of the foam with a black sharpie.

Tomorrow I will explain how I filled the remaining voids and start glassing the seams.

thanks for following. I apologize for picture orientation I can't figure out how to correct this.