Old fridges
I've been a commercial refrigeration repairman for over 30 years. A vintage refrigerator is likely to be more reliable than a new one, provided that the refrigeration system itself has never been opened. This can usually be determined by checking for the presence of add-on charging valves, as most units are charged and then sealed at the factory. The problem is that if someone has gone into the system and they're inexperienced or just sloppy, foreign substances like air and moisture can be introduced; these are a death sentence for hermetic compressors. The exception would be the REALLY old units with belt-drive compressors. These have service valves on the compressor itself. However, since the electric motor is outside the refrigerant flow, these systems are not going to be as seriously affected by improper charging procedures. One nice thing about them is that if the motor is bad, it can be easily repaired or replaced. The weak point of belt drive systems is the shaft seal where the drive shaft comes out of the compressor crankcase. Occasionally you'll get one that leaks, and replacements are getting hard to find. If a shaft seal is leaking, there's also a good chance that the bearings are worn as well. Hermetic systems-the ones with sealed compressors-are very sensitive to the presence of air and moisture; if these substances have been introduced into the system by sloppy or inexperienced repairmen, the electric motor in the compressor will likely fail if it hasn't already. Also, older units use R-12, which has been phased out. If you can find it, it's more expensive than cocaine! The last 30-lb. drum I purchased, about 3 years ago, cost me $1100. The "drop-in" substitute, called "Hot-Shot," works o-k, but don't use it if the internal compressor components (like the connecting rod, piston, etc.) is aluminum. Some of the extremely old units (pre 1925-30) use rather hazardous refrigerants; some early G-E "monitor tops" (the picturesque units with the compressor on top) use methyl chloride (poisonous and unobtainable). I got a nasty surprise once when working on an ancient belt-drive commercial box; it was charged with sulfur dioxide. This gas, when it encounters moisture, forms sulfuric acid. This is what happens in your lungs if you breathe it in, and it can be fatal. If working on an old refrigerator, ALWAYS check the nameplate for the type of refrigerant. If there is any doubt, consult an EXPERIENCED mechanic, or just leave it alone. Bottom line; if you have a vintage fridge with a hermetic system which hasn't been opened, it's probably good for the duration; any parts which might fail, like the start relay or thermostat, are easily replaced with universal replacements. If it's a belt drive system and isn't leaking at the shaft, it's also a good bet. Anything else-leave it alone.
