Best Fridge

PlethoraOfGuns

Adventurer
Yep, insulation is a huge chunk of the efficiency that allows us to run a fridge on wheels. Put a fridge in a vehicle? Add more insulation to it! But I think the whole cold air thing falling out is negligible. Fridge full of just air? Yes, a problem if the cold air falls out. If your fridge is full of cold items , those act as a thermal battery. No worries of you open the door for such small amounts of times.

I also looked at those Dometic 12v units a few months ago when they came out. Great! A fridge that can be cabinet mounted and made to go into a vehicle! But looking at their specs made me back-peddle several blocks. 156w draw on 12v? That's 13amps!!! 3-4x more amp draw than the other 12v fridges on the market. Yes, I know how duty cycles work, but c'mon. That would take a huge battery bank and solar setup to power.
 

part time nomad

Adventurer
Funny you should say that! I only came across them the other day and I thought the power consumption seemed high, but that was without looking into it,
 

TheRealPapaK

Active member
Yep, insulation is a huge chunk of the efficiency that allows us to run a fridge on wheels. Put a fridge in a vehicle? Add more insulation to it! But I think the whole cold air thing falling out is negligible. Fridge full of just air? Yes, a problem if the cold air falls out. If your fridge is full of cold items , those act as a thermal battery. No worries of you open the door for such small amounts of times.

Th extra insulation works both ways. The fridge actually creates heat and needs to get rid of it. The Unique manual states that it is optimum to have 3" of air space all around the fridge for air flow. I have a cabinet door I won't be using behind where the fridge is going to go. I was going to put extra insulation over the door because the it is all aluminum and even though it is insulated, it has a ton of thermal bridging. I was actually thinking of not insulating that so in the winter it is cool and in the summer it could help move the heat from the fridge away...I need to put a little more thought into this....

I agree the top loaders are probably slightly more efficient but with all the thermal mass and how little air there actual is in a filled up fridge, I think the difference would almost be negligible.
 

PlethoraOfGuns

Adventurer
3-5amps is manageable in a vehicle fridge. Anything higher than that is not going to work in our applications. Not sure what Dometic is doing. The other companies have figured it out decades ago.

The fridge only produces heat in the back, where the condenser coil is. The company probably just says 3" all around to cover themselves when people jam these things up against walls. Yes, you can seal the fridge on the top, bottom, and sides, but the rear needs adequate ventilation.

I'm sort of in the same pickle as you. I have about 4-5" of air space and bare exterior aluminum behind the fridge. I was going to leave it bare with just a vent to the outside back there. But someone pointed out that when the sun hits the aluminum exterior, that heat will transfer into the space behind the fridge. So I'm going to insulate the inside of the aluminum exterior wall with some XPS foam and put a vent on top of the wall and the bottom of the wall in order to get a convection effect in the ventilation. Most people just have the whole fridge inside living area and deal with the heat the fridge puts off. I'm probably overthinking it, trying to get the heat to the outside of the vehicle.

I'm also looking for a vent that can easily be removed like a door so I can get access to the rear bottom of the fridge. There is a troubleshooting fault light and the electrical connections back there. Any suggestions would be great.
 

JaSAn

Grumpy Old Man
For those of you that have had success running a 120V mini or dorm fridge:
- what refrigerator make & model are you running?
- is a pure sine wave inverter required?
- is it built in and does it have free space around the sides?
- how do you keep the door closed?

Thanks, jim
 
Last edited:

part time nomad

Adventurer
Regarding insulation! I have a fridge / freezer in the big truck, I put extra insulation top and sides, as it is cabinet on the the fridge there anyway. I left an air gap underneath, as the fridge motor is lowdown at the back, so it can draw air there ok.
I left a 3 inch gap at the back, but I cut a 5 inch round hole through the body (2 inch GRP insulation) right behind the fridge motor fan, I put a grill on it, and then I machined the bit I cut out, to be able to be refitted for cold climate.
I also fitted a small 12 volt fan at the top of the rear cavity, that I can turn on in hot climate, it blows through the wall into the bathroom/ shower, all works well.

To make the fridge more efficient inside, a small fan near the cold plates, circulating the cold air makes for an even distribution.
 

TheRealPapaK

Active member
My Unique fridge was delivered and has a couple small dents at the bottom of the door. Interestingly enough it only has feet on the front of the unit. This makes it site at an odd angle. When I tipped the fridge over to see if they were missing, I noticed there is no real place for feet or brackets to attach. I would be interested to see what you come up with Plethora, I was thinking of drilling some holes in the bottom of the cabinet where the feet attache to the fridge and bolt it down there. Wedge it tight every where else with foam maybe....
 

part time nomad

Adventurer
You should not really need feet at the back! I think mine has rollers, that makes it easier to slide in to the cabinet space. You can the level it on the front feet. I bolted mine in and then packed the insulation. Be very careful where you drill near the cabinet.
 

Raul

Adventurer
For those of you that have had success running a 120V mini or dorm fridge:
- what refrigerator make & model are you running?
- is a pure sine wave inverter required?
- is it built in and does it have free space around the sides?
- how do you keep the door closed?

Thanks, jim

- Mine is a Magic Cheff but I think all of these generic minifridges are made at the same place.
- I've been running it with a mod wave 1100W Krieger (https://www.amazon.com/gp/product/B00T564EIY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1) with no problem. I "upgraded" to a 1500w pure sine wave (https://www.amazon.com/gp/product/B088LZ1L3W/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1) and was not able to run it. Now I got a new 1200W pure wave ( https://www.amazon.com/1200Watts-In...ords=giandel+1200w+pure&qid=1608236350&sr=8-2 ) and seems to work fine. A good mod wave seems to be fine.
- YES, YES, YES. A fridge gets heat from the inside and evacuates it to the outside. They used to have coils in the back but, now the coils are build in the middle of the side walls. Let the fridge run and see where it gets hot. Once you find it, do not cover that area. I've added CPU cooling fins on those spots.
- I've put as much insulation as possible on the non-hot areas, including door. Hot areas are open.
- I got this latch : https://www.amazon.com/gp/product/B00X8MFCEG/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1


The drawers on the left are spaced out from the hot wall. The right side is open. Page 10 on my build has more details.

1608236076530.png
 

PlethoraOfGuns

Adventurer
My Unique fridge was delivered and has a couple small dents at the bottom of the door. Interestingly enough it only has feet on the front of the unit. This makes it site at an odd angle. When I tipped the fridge over to see if they were missing, I noticed there is no real place for feet or brackets to attach. I would be interested to see what you come up with Plethora, I was thinking of drilling some holes in the bottom of the cabinet where the feet attache to the fridge and bolt it down there. Wedge it tight every where else with foam maybe....

Yep, only adjustable feet on the front. But why do you need to adjust? It sits flat when the feet are screwed all the way up. There is no such thing as level when you're on 4 wheels! I just got my fridge in. Here is what I did:

PXL_20201218_154822073 copy.jpg
Got a thin piece of galvanized angle iron, happens that 2"x2" worked perfect for my cabinet, and bolted it to the bottom of fridge using the stock threaded holes for the hinges.

PXL_20201218_154801002 copy.jpg
There are mounting holes on both sides, I just needed to source another M5 bolt to secure the side opposite the hinge. Used a few washers to take up space where the hinge bracket would be on the other side.

PXL_20201205_005611287 copy.jpg
And that holds it in great. The top cannot come forward out of cabinet because it sits up tight against some foam. There are more photos of the rest of fridge fitting on page 9 of our P30 Grumman build. Whatever you do, maybe try not to make any new holes in fridge. I'm sure it's all just sheet metal and foam inside, but may void warranties and all that. I thought about mounting brackets to sides of fridge, but this mounting system is super solid. Kind of a pain to get fridge out actually. It's a snug fit.
 

TheRealPapaK

Active member
Awesome thanks. Yeah something is up with my fridge because it is tilted back still with the feet screwed al the way in. Thanks for the pics. This helps.
 

TheRealPapaK

Active member
This is what I ended up doing behind my fridge. It looks a little ghetto but basically the fan draws air out from the top and hopefully it will pull cool air into the bottom. Let thermodynamics give it a bit of a flow bottom to top to pull the heat out. The fan is on a switch. I might put it on a thermostat at some point
45BF3845-5D23-4938-A2BF-77C16C65221E.jpeg
 

part time nomad

Adventurer
I did a simular thing, but just had the fan at the top of the rear cavity, on a switch. it vents into the shower (at the top) I also cut a vant in the side of the van to draw cool air (would have liked to had it underneath but the tanks are there) I can close the vent for cold weather.
 

Forum statistics

Threads
185,533
Messages
2,875,610
Members
224,922
Latest member
Randy Towles
Top