18 year old refrigeration -- fix it or ditch it?

[Richard Kollmann]

Originally Posted by alaskasail

I also have a very old reefer that amazingly, still works, but I'm thinking that improvements in refrigeration systems might provide a smaller and more efficient unit. With the new technology in electric motors that might be true. Is it?

A 12 volt refrigeration in Mexico with a box size of 4 cu ft or larger probably would not realizes a significant improvement from today's mew compressor efficiency. Small icebox conversions in cooler climates do benefit from the new variable speed compressors. Other marketing gadget technologies offer little improvements to the older systems.

[s/v Jedi]

Originally Posted by davil

===========================================
Hi Jedi
If I understand what you did,was to accommodate the box into a space,not just the cooling unit from the Dometic.
My fridge space (30 ft boat) is not large enough to fit the whole box,is there a way to disassemble the cooling system and install it inside the fridge existing space?
Otherwise will have to find room for a free standing box somewhere in the cabin/vberth/pilot berth.
thank you

Disassembling the portable fridge/freezers takes out most of their advantages so I would never do that. Just find room for the box, they come in many different sizes

[mark0978]

Make sure that whoever you use to do the work has a clue about what they are doing. I'm now buying tools to fix my own fridge after this AC guy (highly recommended) has ruined my fridge here in Isla Mujeres, Mexico. His name is David Caviche, avoid this guy like the plague. Didn't vacuum the system, didn't use nitrogen when brazing.

[a64pilot]

Originally Posted by gamayun

My Adler Barber compressor is probably original so 31 years old, but it is noisy and sucks up a lot of power.. If there are more efficient ones than the one you're currently using, than that might also be a consideration.

To my knowledge there has unfortunately been no breakthrough in compressor design to increase efficiency.
Most of the efficiency increases on newer systems have come from much larger evaporator / condensers that allow the compressor to operate more efficiently due to not having to drop the refrigerant temp so low and the ability of the larger condensers to dissipate the heat.
All that could have easily been done 50 yrs ago, but the larger pieces cost more money to manufacture.

I wish someone would invent a more efficient compressor, but as far as I know it hasn’t happened.
I don’t believe the Sawafugi swing compressor is any more efficient, near design though.

[170122]

IndelB Isotherm Webasto are very good units, Quick disconect fittings sometimes present leaks, but often because they are not tight, recharge the system one more time, the turn off your unit, wait about 20 minutes, then test for leaks using a good water foam solution, be patient, if the leak is not present start the unit, wait 5 minutes and test for leaks on those fittings. Eventually if the leak is located on one of them, disconnect it, all the way..

[Richard Kollmann]

Originally Posted by a64pilot

To my knowledge there has unfortunately been no breakthrough in compressor design to increase efficiency.
Most of the efficiency increases on newer systems have come from much larger evaporator / condensers that allow the compressor to operate more efficiently due to not having to drop the refrigerant temp so low and the ability of the larger condensers to dissipate the heat.
All that could have easily been done 50 yrs ago, but the larger pieces cost more money to manufacture.

I wish someone would invent a more efficient compressor, but as far as I know it hasn’t happened.
I don’t believe the Sawafugi swing compressor is any more efficient, near design though.

Heat transmission of evaporators and condenser’s knowledge was available more than 50 years ago. The problem is applying this knowledge of thermodynamic heat flux of a boats ice box conversions installations. The capacity of evaporator is selected based on box cubic feet and the best K factor sizes possible to handle compressor matching output.

Improvements in Danfoss 12/24 volt small compressors since 1980 were limited in fixed output till 1995 were single cylinder cubic inch changes from 2cc to 2.5 cc. In 1995 the fixed speed compressor manufacturing stopped and was replaced with a variable speed models. Unfortunately today selecting a good thermodynamic design is up to the purchaser and installer.

[a64pilot]

Richard, I’ll adjust from my own observation, and there may be some placebo effect here of course, but I think the AEO module is a step forward as well.

But I guess what I was saying is unfortunately, no one has built a better mouse trap as far as a compressor is concerned.

I remember when Mazda first put the Wankel engine out to the public, I was convinced it was a better mouse trap, but was wrong of course.
GM’s version was going to be stellar

[Richard Kollmann]

Originally Posted by a64pilot

Richard, I’ll adjust from my own observation, and there may be some placebo effect here of course, but I think the AEO module is a step forward as well.

But I guess what I was saying is unfortunately, no one has built a better mouse trap as far as a compressor is concerned.

I remember when Mazda first put the Wankel engine out to the public, I was convinced it was a better mouse trap, but was wrong of course.
GM’s version was going to be stellar

As the years pass we all have to look at technical decisions that were not the best. My learning curve included:
A 48 Kaiser car that used no lock washers and leaked oil so bad when I parked it oil dripping from rear bumper left the bumper print on the roadway.
A Studebaker pick up.
A cabin cruiser with a Crossly 26 horse power car engine boosted to 44 HP.
A 19 foot sail boat with a 1/2 horse gas power belt drive propeller.
I also bought a new power boat with an out drive V8 engine that had a very short life in salt water.
Not to mention a 172 I only flew in twice twice.

[deluxe68]

Originally Posted by Q Xopa

Yes agreed. Im a big fan of some water and wash up liquid in a spray bottle. Have even used a rag soaked in a handy bucket of soapy water too in a pinch. Spray bottles are cheap and easier because you can spray from a distance hard to get your hand into spaces.
A bit off topic but the soapy water trick can also work for fuel, and other line hard to find, leaks. If you get a bit creative with regulated compressed air.

I used to use a purpose-made product, it seemed to work better than soap bubbles which dissipated fairly quickly.

[a64pilot]

Originally Posted by deluxe68

I used to use a purpose-made product, it seemed to work better than soap bubbles which dissipated fairly quickly.

I’ve seen those leak detection fluids, it reminds me of buying bottled water

[RaymondR]

Originally Posted by Richard Kollmann

As the years pass we all have to look at technical decisions that were not the best. My learning curve included:
A 48 Kaiser car that used no lock washers and leaked oil so bad when I parked it oil dripping from rear bumper left the bumper print on the roadway.
A Studebaker pick up.
A cabin cruiser with a Crossly 26 horse power car engine boosted to 44 HP.
A 19 foot sail boat with a 1/2 horse gas power belt drive propeller.
I also bought a new power boat with an out drive V8 engine that had a very short life in salt water.
Not to mention a 172 I only flew in twice twice.

I had a real good chuckle when I got to the 19 foot sail boat with the 1/2 horsepower belt drive. With the belt drive losses you probably had about a 1/4 horsepower at the prop.

[Richard Kollmann]

With no help or hindrance from wind and a small displacement sailboat hull you might be surprised at what .200 Kw at propeller can do.

[RaymondR]

Originally Posted by Richard Kollmann

With no help or hindrance from wind and a small displacement sailboat hull you might be surprised at what .200 Kw at propeller can do.

Hell, 200kW would probably get most small sail boats up onto the plane??

[Richard Kollmann]

Originally Posted by RaymondR

Hell, 200kW would probably get most small sail boats up onto the plane??

You missed the Decimal point in front that made it read two hundred of one KW.

[stieve]

It's totally upto you like if you want to spend some money then you can go for a new one and if you're low on budget then i suggest you to fix it. for fixing you will need some tools like tube cutter, swagging tool and here is the complete list https://www.searspartsdirect.com/art...ce-repair.html and I have also read this guide
about different power tools list you must have. I hope it might help you.