Tearing apart a mini fridge and use it for the built in coolbox?

[rotorman]

I was thinking if it would be possible to buy a mini fridge, like the waeco cfx50, take it apart and use it's part to cool my built in coolbox.

Not sure if it would be more cost effective, but here (in Singapore) more readily available then separate components.

[john61ct]

Funny lots of that gear is flowing through there or Hong Kong from its factories to get over here.

You'd likely need a good experienced tech to help with that project.

More likely to find an inexpensive helper in Malaysian yards than Singapore proper.

[kentobin]

There was a diy article were someone recently tried this. The condenser coils dissipate the heat collected by the refrigerant. In the mini-refrigerator he used the condenser coils were not a separate removable unit but were attached directly to the case of the refrigerator which is used to help get rid of the heat. The coils couldn't be removed from the case and even if they could you'd have to figure out how to get rid of the heat that the case was absorbing.

No idea if all mini-refrigerators are built this way.

You'll have to find a parts breakdown of the refrigerator you want to buy to verify if it can be used.

[RaymondR]

I discovered years ago that buying a small portable fridge was sometimes the cheapest way of acquiring a compressor. Working from memory I recall that I was quoted about A$850 for a new Danfoss compressor and controller and could buy a portable fridge from a camping store with the same compressor in it for about A$500.

The condenser on my first boat fridge was made by winding 1/4" tube around a pipe and enclosing it in a piece of 4" poly down pipe with a computer fan in the bottom. Cheap to build and worked really well.

[Cheechako]

Out of curiousity I looked at mini fridges once wondering the same thing. It appeared to me that too much is built in and not very useable. The evaporator especially.

[kenbo]

Or you could buy a complete set of matched components from NovaKool for about $800

[Simi 60]

Originally Posted by kenbo

Or you could buy a complete set of matched components from NovaKool for about $800

In Singapore?

[john61ct]

Dometic/Waeco is worldwide, has dozens of brands, most stuff is made there shipped hete, and there is plenty of yachting going on that part of the world.

And even stuff from vendors that refuse to sell onto the U.S. market is readily available anyway, just pay a little extra for shipping, amazingly cheap these days.

[kenbo]

I admit I'm not familiar with Singapore customs but the shipping shouldn't be too harsh.

If the OP was planning on cannibalizing a mini fridge himself he's going to need to have or have access to a vacuum pump, torch to either braze or solder with, nitrogen to purge if brazing and a manifold gauge set to add Freon.

It certainly can be accomplished but there are barriers to overcome. I was giving him a plug and play option to base his value proposition upon.

[Stu Jackson]

Originally Posted by kenbo

>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>>>>>
If the OP was planning on cannibalizing a mini fridge himself he's going to need to have or have access to a vacuum pump, torch to either braze or solder with, nitrogen to purge if brazing and a manifold gauge set to add Freon.

It certainly can be accomplished but there are barriers to overcome. >>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>

Good points. In addition, air cooled "marine" systems have fans for the condenser coil, which may not be present on packaged units. This was noted earlier when mention was made of using the box as a heat sink of sorts.

Also, when I replaced my electronic module on our A/B system last year, it was important to obtain the module with the proper amount of "plugs" going to the compressor. IIRC, there are both three and four pin plugs.

Sometimes mixing and matching is harder than it first appears.

[Infatuation]

I took one of those smallest fridge's I bought at a pawn shop for 40 bucks and took it all apart very very carefully with the coil wrapped in foam insulation serpentine around the box. I then installed the cooling box inside my ice box and carefully wrapped the coil around a 4 inch pvc pipe. Plugged it in and to my surprise it worked beautifully for about 4 years. To be honest all the while I was doing it I said to my self "this will never work" because for sure it was going to develop a leak, but it didn't. I don't think I would try it again. I feel I was just lucky.

[Rorzech]

I think thats a great idea. It's not that hard to do. You make up you cylindrical condenser like the previous guy said but 2" poly is big enough. 1/4" tube goes straight up the middle and coils all the way down to the little Dryer. If you use copper to copper you can use silfos . You might be able to get it to melt with Mapp gas .Don't cut into the fridge pipes until you have every thing ready intalled waiting for transplant. Don't let pipes sit around open keep everything plugged as long as possible. Use a corner of a file to score the capillary tube both sides and bend to break so you end up with a nice clean hole in it. Sand cloth every joint you sweat together and sweat on a charging stub on the little dead end stub on the side of the compressor that has a schrader valve (out) so all joints are made with that stub open so your joints won't leak. When done charge it with vapour and let it blow out . repeat two more times. Yes its wasteful but you won't need a vacuum pump. Those new tiny fridge compressors use very little power. Try it. Don't for get goggles. You can use those little cans about 3 of 134A meant for auto A/C. Your evaporator can hold half of one when done. If frost comes back to compressor then bleed the schrader stub a bit and wait two minutes and repeat until you see frost disappear off suction line. Boost efficency by wrapping Capillary a suction line together tightly with aluminum tape then electrical tape tightly then foam tape. Some times those two tubes are soldered together the full length.

[Cheechako]

One wonders how they can make and sell a mini fridge at $120 complete. That probably includes 50% profit (?) for the final seller, profit for the maker, and absorbs shipping the unit once or twice. Compare that with a "marine fridge" cost.

[Rorzech]

You can easily make an evaporator out of 5/16" soft copper tubing and bend it to any shape you want. You can sandwich it between to aluminum plates to make any size cold plate you like.

[shane.h012]

When I look in to it, I found the amps used was 3 to 4 amps on a 240v mini fridge, them running an inverter to power in when sailing.... so say 3amps now becomes 60amps on a 12v supply from a battery, so gave up on the idea, as Waeco fridges run on 12v 5amps, I know it only runs when cooling, but 5 amps 12v or 5amps 240v with inverter when sailing makes a lot of difference on 200amp battery’s that you want to last a day at least between charges...