Insulation on top of propane fridge

[Random01]

Hello. I had been troubleshooting my Dometic fridge in propane mode and found that there is no insulation in the large space above the fridge.
The space is at least foot tall.
The manual says that space must be filled with insulation.
There is a thin plywood plank creating some barrier for air but clearly not enough, I think there are air circulation issues, the fridge is in the slide.

What kind of insulation should I use for space this large?
I'm thinking foil backed fiberglass rolls but wonder if fiberglass fibers can get into the burner or other parts behind the fridge
Can't find any pictures or videos of how it should be properly done.

[Old-Biscuit]

Roll of fiberglass is fine...........burner is completely away down at bottom

What Model is the Dometic?
Installation Manuals are available showing how fridge should be installed/vented etc in slideouts

Service manuals also available


This one covers majority of Dometic Fridges
https://myrvworks.com/wp-content/upl...All-Models.pdf

[Random01]

Originally Posted by Old-Biscuit

Roll of fiberglass is fine...........burner is completely away down at bottom

What Model is the Dometic?
Installation Manuals are available showing how fridge should be installed/vented etc in slideouts

Service manuals also available


This one covers majority of Dometic Fridges
https://myrvworks.com/wp-content/upl...All-Models.pdf

I have the installation manual.
It only mentions insulation but doesn't discuss type of insulation, says insulation, baffles or seal must be used to block this space off.

The fridge is properly installed and vented, except this space was not filled as required, and this is the original factory install.
Fridges in slides often have circulation issues even when properly installed.
Im about to install extra fans but I can not sleep when fans are operating and need to address passive air flow issues first, fans are for emergency use only. I live in RV boondocking full time and it all is a big deal

I thought of just taping something like rigid foam piece to block this space off from air flow instead of filling it, with high temperature tape, as an alternative to fiberglass batts. Not sure what's better.

Also not sure how to prevent fiberglass one shifting and desintegrating, manual has a warning about pieces of insulation falling down to the back of the fridge and causing problems. It seems like fiberglass insulation must be completely blocked off by some seal? Manual says to firmly attach all insulation, but doubt its possible with fiberglass, so not clear on this either

[bigb56]

Originally Posted by Random01

I have the installation manual.
It only mentions insulation but doesn't discuss type of insulation, says insulation, baffles or seal must be used to block this space off.

The fridge is properly installed and vented, except this space was not filled as required, and this is the original factory install.
Fridges in slides often have circulation issues even when properly installed.

I thought of just taping something like rigid foam piece to block this space off from air flow instead of filling it, with high temperature tape, as an alternative to fiberglass batts. Not sure what's better.

I used some aluminum (4" dryer ducting from HD) to make a smooth, curved transition so the hot air is channelled directly to the upper vent instead of filling the dead space and creating turbulence. The aluminum is very easy to work with and can be cut with scissors. See pics. Then you can fill the space behind it with your insulation. I'm also attaching a good source for proper fridge venting, if your rear clearance is too wide you can fasten some 1" foil backed foam insulation to the wall.

I did a number of improvements and brought my Dometic fridge's performance from terrible to remarkable.

https://www.fridge-and-solar.net/fridge_vent.htm

[wolfe10]

Have you compared clearances (particularly on the back of the refrigerator) with the specs in your installation manual?


Particularly in a slide, consider adding 2 12 VDC muffin fans at the top of the evaporator blowing UP.

[Random01]

Originally Posted by wolfe10

Have you compared clearances (particularly on the back of the refrigerator) with the specs in your installation manual?


Particularly in a slide, consider adding 2 12 VDC muffin fans at the top of the evaporator blowing UP.

As I said in my above post, Im about to add extra fans but I do not want them to ever have to run at night. I only run my fridge at nights and cant sleep when any fan is running neither I want any extra battery drain. So first I must address passive air flow by addig missing insulation, I need clarifications specifically on insulation (as to clearances they are ok)

[Paul_D]

After addressing the void issue, another option is installing the Fridge Defend with the external fan kit. The fans are quiet and only run when required.

[Random01]

I just want to install insulation. Then I will install top louver fans, but wont be installing anything else.

Can someone clarify my insulation questions please?

[Old-Biscuit]

Originally Posted by Random01

I just want to install insulation. Then I will install top louver fans, but wont be installing anything else.

Can someone clarify my insulation questions please?

From the manual
INSULATION NOTE!- Any insulation used must be securely attached to the enclosure walls and ceiling in order to prevent it from shifting when the refrigerator is installed in enclosure. -

If there is a void space above the refrigerator, insulation
should be secured with spray adhesive to the top of the
refrigerator to fill the space. -

Trim insulation. Cut it 2-3” shorter than the depth of the
refrigerator box, see FIG 3 below.-

Insulation must not come in contact with the cooling unit!
Loose insulation can obstruct air flow creating cooling
issues and possible damage to the refrigerator

[Toby Dog]

If computer fans are used to vent heat in a slide install you'll never hear them.
After all there was one in there already.

[Random01]

I decided to just tape a piece of decorative aluminum sheet using heat resistant tape to close up that gap. Once I get somehere where I can buy Polyiso, eventually, I will add it as a backing for aluminum


Many roll/sheet insulation types are either flammable or can't take much heat, the only acceptable one seems to be polyiso that can take 120 Celsius but good luck finding it anywhere where I'm traveling. (do not want fiberglass, too much risk of pieces falling down to the fridge, and it seems to be very expensive too now, the top of the fridge has some flat insulation on it already, dont really need to fill entire space)


Therefore, the question had been solved, thank you.

[Random01]

Originally Posted by bigb56

I used some aluminum (4" dryer ducting from HD) to make a smooth, curved transition so the hot air is channelled directly to the upper vent instead of filling the dead space and creating turbulence. The aluminum is very easy to work with and can be cut with scissors. See pics. Then you can fill the space behind it with your insulation. I'm also attaching a good source for proper fridge venting, if your rear clearance is too wide you can fasten some 1" foil backed foam insulation to the wall.

I did a number of improvements and brought my Dometic fridge's performance from terrible to remarkable.

https://www.fridge-and-solar.net/fridge_vent.htm

Yes, that's what I decided to do.
I got metal cutting tools in my RV and can cut decorative aluminum they, seem to sell it in small sizes but will look into ducting aluminum too. Its very hard to buy materials in these small remote towns.

I don't see a reason to fill entire space behind the aluminum, for which fiberglass would be the only realistic option here. The fridge top got some kind of reflective insulation board covering it already so it got some protection from the heat. I just don't want heat to travel through alumnimum back into that sealed off top space, so I think Polyiso board piece or even double layering it behind aluminum should be enough.

I don't really want to drill into anything around there so hopefully reflective tape which I think is heat rated 230-250F will do

[bigb56]

Originally Posted by Random01

Yes, that's what I decided to do.
I got metal cutting tools in my RV and can cut decorative aluminum they, seem to sell it in small sizes but will look into ducting aluminum too. Its very hard to buy materials in these small remote towns.

I don't see a reason to fill entire space behind the aluminum, for which fiberglass would be the only realistic option here. The fridge top got some kind of reflective insulation board covering it already so it got some protection from the heat. I just don't want heat to travel through alumnimum back into that sealed off top space, so I think Polyiso board piece or even double layering it behind aluminum should be enough.

I don't really want to drill into anything around there so hopefully reflective tape which I think is heat rated 230-250F will do

Kaowool would work too, comes in board or blanket form and is good to 2000 degrees F. I had some left over from a forge build and I used it to wrap the flue vent where it passes through the side of the coach.

The best foil tape I've found is Nashua 324A, it's thick, sticks like nobody's business and works between -25F to 325F. Been using it exclusively for many years.

Both available on Amazon of course.

[Random01]

I'm not in a position to receive Amazon orders for a few weeks. I have a roll of aluminum tape which I recall 230-250F rated which I earlier used to secure hood engine heat shield replacement. It might be not the best one but I think should do. Also got to work with stuff available from rural hardware stores, aluminum sheet I should be able to get it.