GE Globe-Top Monitor Fridge

[phil]

I do know that a lot of times newer fridges ( like 50's to 70's) loose some of the charge. maybe not a broken line but maybe through things like internal shaft seals in the compressor. Surely there must be at least a T somewhere otherwise how did the original manufacturer charge it?

I know there are different fittings that might signify the type of gas or something. I bought one of those refill kits for car AC units and it came with a pressure gauge and the cans to fill it as well as some seal swell stuff and new fittings since I guess it is a newer refrigerant. There may be some different opinions on whether the seal swell stuff works. but it is a can of compressed gas similar to the cans of gas to fill it.

I'm not fridge expert but Ive seen a lot of old wiring. Ive got some that has a fiber cloth cover that's good for things like that. heat resistant insulation. remember if the unit gets hot that may have helped degrade any wiring. replacing wiring is usually straight forward if you can just go one by one , if not take pics , use labels you can get tape with numbers and number the wires if it gets involved. sometimes in radios I want to keep the cloth wire if it is visible but if it isn't and you just want it safer and if the wire itself is OK. You can sometimes just slip a piece of heat proof wire cover over what you have. That's handy if one end is hard to get to. as previously pointed the dust can cause airflow issues. also keep your eyes open for asbestos if you see stuff that looks like fiberglass don't muck with it. there is a replacement that is more like fiberglass that can be used to replace heat shields. a lot of modern wire is plastic coated and you can get wire with insulation designed for the high temperatures. if you just need a bit you can probably rob it from an old stove.

sometimes I have old wire that shows. older stuff didn't use heat shrink it used stuff called spaghetti. it looks similar to heat shrink but it is more like an oil cloth with fabric and won't shrink, you can pull that over wires to keep them looking period correct. I often see it used in windings for motors where they need a bit more protection from the heat and vibration.

If you have specific questions I do work right near where they train refrigeration techs so I could wander over with a specific question for an instructor and I'm not very savvy myself about the old refrigerants or conversion so don't go by me on that.

I wonder if you look into it you might find some of these gasses run at different pressures and so need a different pump seal design than others.
the compressor compresses the gas and makes heat. then when the compressed gas reaches the small orifice it creates cold. the pump and pressure and the size of the orifice will probably be tailored to the refrigerant. I just sat through a demo of an instructor in training explaining how it works. He said that the orifice in a common fridge is fixed but when they go into commercial coolers and things they may be able to adjust that. I think there are ways to fine tune the commercial orifices as needs vary. There will be relationships between the CFM of the pump, the pressure, the gas and the size of the orifice and I think if you change one part of that equation you are starting to re-engineer and maybe that's possible.



Phil