Modern refrigerators have gotten pretty complicated!
I took the opportunity to actually read the service manual (which I had downloaded a few years ago) for our fancy refrigerator. And what I realized, particularly after looking at the wiring diagrams, was how complicated the darn thing was. And it made me realize how complicated refrigerators - and other appliances - have become over the years.
I mentioned before my 1955 Frigidaire, which was streamlined like a diesel locomotive (oddly enough, made by the same company!). Those old fridges were pretty simple. I guess the old GE "Monitor Top" were even simpler, but the idea was the same. The refrigeration unit was hermetically sealed - every connection silver-soldered, so no leakage of refrigerant over time. The compressor sat on a big spring, immersed in oil, in a sealed bomb-like container. The unit was a big insulated box, basically, with the evaporator "coil" comprising the freezer compartment inside the box. Whatever you put inside this "coil" (which was two layers of corrugated stamped aluminum, basically) would freeze. The rest of the fridge would stay cool, but not freeze. A simple bi-metallic thermostat would control temperature.
Of course, that was why it was said never to defrost your refrigerator using a sharp knife to remove the ice. You could puncture the aluminum and all the "Freon" (a trademark of E.I. DuPont de Nemours and Company) would leak out. But speaking of defrosting, those early refrigerators had no provision for defrosting themselves, and over time, the freezer "box" would ice up to the point where you could not open the freezer compartment door. So you periodically had to unplug the thing and remove all the food and get towels to catch all the melting frost on the freezer coil. It was tedious.
Enter the swinging 60's and "frost-free refrigerators" and the start of complexity. In order to automatically defrost, they added a "defrost timer" which would periodically heat the freezer coil either with an electric element or by reversing the refrigeration cycle. This would cause the frost to melt and it would drain off into a drain tube and into a tray underneath the refrigerator, where it would evaporate over time. Some units have the compressor sitting in this tray, so that the water evaporation is aided by the heat from the compressor.
About this time, the two-door refrigerator became the norm. The freezer compartment was separate from the refrigerator compartment, instead of being a compartment within. As such, there was (and is - they still make these "box" refrigerators) a passage between the freezer compartment and the refrigerator compartment, to let cold air flow into the refrigerated section. Since the freezer is located above the refrigerator and since cold air sinks, the air flows by convection from the freezer to the refrigerator. A small adjustable flap can be used to control this flow.
Still pretty simple, although now you have a "defrost timer" to break down, and if it does, either your freezer will frost over or, if stuck in defrost mode, it will get warm and stay warm. The defrost timer is a simple electromechanical "clock" with a tiny motor that wears out over time.
You may recall Mom yelling at you to close the refrigerator door for "wasting electricity" - which was true. But she learned this from her Mom, who was concerned more about having to defrost, before the era of frost-free refrigerators. The more you open and close the door, the more humid air you let in, which condenses on the freezer box. The longer the door was left open (and more often) the more often she would have to manually defrost the refrigerator.
We are running into this problem at the Parcheesi club - the fridge (a frost-free "box" refrigerator) has a door seal leak. It lets in warm, moist air (we are in Georgia, on a barrier island) and this condenses on the freezer coil, which is a "spiny-fin" (think: tinsel) coil which is located behind a small wall. The amount of humid air overwhelms the defrost cycle, so it never fully defrosts. Over time, ice builds up and this clogs the drain tube, so the water pools in the freezer and also passes through the opening into the fridge compartment, leaving a puddle on the glass shelves. As such, I have to manually defrost this thing once a year, although a small door adjustment seems to have fixed the door seal issue (so far).
Another development around this time was the touting of capacity - often at the expense of insulation. Electricity was cheap, so why bother putting inches of insulation into the refrigerator box? Just run the compressor some more - and you can advertise more cubic footage over your competitor! Efficiency was degraded, of course.
When we moved back to New York when I was a kid in 1968, our new house had a drawer freezer on the bottom. How fancy! It even had a primitive semi-automatic ice maker (a tray that filled automatically, but had to be flipped over to "dump" the ice out. It never worked well, particularly with hard water). As you might imagine, since cold air doesn't rise by itself, this meant you had to have a small fan to move cold air from the freezer compartment to the fridge in order to keep it cool. It was either that or have a complicated system of two evaporators and two thermostats. A fan was simpler, but still an additional level of complexity.
Fully automatic icemakers appeared about this time. You can still install one - they are cheap - in a standard "box" refrigerator, most of which are pre-wired and pre-plumbed for them. I've installed a few in my day. They use a rotary mechanism to push out curve-shaped cubes that we are all familiar with.
The "side-by-side" refrigerator became a thing about that time. A neat idea, but again, with cooler, denser air wanting to sink, a fan between compartments was needed. But it did make it easier to allow for "ice through the door" as the freezer was now elevated. The newer, fully automatic ice makers are coupled to a dispenser which uses a spiral screw to feed cubes when you press the lever - or even crush the ice if you want. So, two more electric motors - one for the ice maker and one for the dispenser - and a solenoid for water-through-the door - and complexity rises yet again.
I won't even address commercial "built-in" refrigerators, which, oddly enough, are often simpler in construction but less reliable. On the KitchenAid site, they exhort me to buy a built-in fridge at the starting price of $12,000. This simply is not an option, even for the people who buy them. In the real gourmet kitchen, they often have two or more of these, and a separate freezer. A more recent trend is to have refrigerators scattered throughout the kitchen, in the form of "drawers" that look like ordinary cabinets. You can spend as much as you want to - but probably shouldn't.
The three-door or "Dutch Door" fridge that we have now, has even more complicated things. Once again, the freezer is located below the fridge, so cold air has to be forced into the upper box with a fan. But now we have a complicated door seal with a folding flap-and-cam mechanism, and a sensor to detect when it doesn't fully close (half the time) and set off a beeping alarm. Digital controls are used, along with a membrane-switch touch-panel, to set and display temperature.
I noted in an earlier posting that we threw out a lot of food when we woke up one morning and saw the door was ajar overnight and the inside temperature was reading 67 degrees. Well, we threw out the food over nothing, in retrospect. The temperature sensor (a thermistor) is located next to the incandescent bulbs that light the cabinet. When the door is open, these bulbs heated up the sensor, which in turn gave a false reading. Replacing the cabinet bulbs with LED counterparts "fixed" this problem. Adjusting the cabinet leg screws so that it tilted rearward more, reduced the tendency of the Dutch doors to remain ajar. It has been a long 18 years with this fridge, and I am just now figuring out its idiosyncrasies. And it has many.
I would buy a simple "box" fridge in a heartbeat, but in our confined "galley" or "pullman" kitchen, a standard door refrigerator, when open, would hit the butcher-block we use for food preparation. A "side-by-side" fridge is one option, but most if not all, have "ice through the door" which takes up half the freezer compartment. Another problem with the "side-by-side" fridge (which we had at the lake house) is that you cannot put a pizza in the fridge, or a frozen pizza in the freezer. They are just too damn narrow!
Speaking of ice-through-the-door, another layer of complexity we saw in our appliance shopping was the Dutch door with ice-through-the-door. Since the upper section is refrigerator, they had to put a huge freezer box in the refrigerator portion so that the ice could come through the door. The door itself has no shelves for storage as the dispenser is located there. As a result, well, you have a pretty small refrigerator as about a third of it is taken up by the ice maker and through-the-door dispenser. Complicated as all get out, too!
And don't get me started on "four door" refrigerators, either!
Granted, a lot of our technology has become far more reliable over the years. Cars today are incredibly complex transportation machines compared to the primitive cars of my youth - which were sold more based on styling than on technology. And yes, we have these esoteric failure modes where some piece of electronics fails and few seem to know how to fix it. But the basic mechanical bits are far more reliable than in the past.
A car in the 1930's would need a "valve job" after 30,000 miles and an oil change and "lube job" every 1,000 miles. A car in the 1960's might go 3,000 miles between oil changes, but it would go to the junkyard before 100,000 miles showed on the clock (which only went to five digits). By then, it would be a rusted-out dented piece of crap with a shredded interior, a motor blowing oil (if it even ran) and a transmission needing overhaul. It would already have been on its second or third set of tires, mufflers, shock absorbers and batteries
Today, the same rednecks who complain about "all this modern computer technology" in their cars, brag to me about how they just put 300,000 miles on their pickup truck with no real issues. Oil changes are 7,500 miles or more and things like transmission and radiator fluids can last 100,000 miles or more. We really have improved the technology. The problem is, the old-school repair methods are just outmoded. No one needs a mechanic who can adjust a carburetor or set the points using a worn Roosevelt dime as a gapping tool (as I learned as a youth).
Similarly, modern appliances require a different skill set than in the past - and an understanding of electronics and their failure modes is key. The refrigeration part of a refrigerator is rarely going to fail (and if it did, you'd scrap the fridge). If you tried Homer Simpson's refrigerator-air-conditioner technique as shown above, you would not "burn out the motor" as Marge suggests. Rather, it would just run all the time, your food would go bad, and Homer's tent would get warmer and warmer as the load exceeded the capacity of the system.
In shopping for appliances, we saw a lot of ill-conceived ideas and "features" which seemed questionable. One refrigerator had one-inch-deep "snack trays" underneath the vegetable crisper bins. They extended well under these bins, but you could not open them up to clean them - or indeed, even retrieve a lost snack piece. I am not sure what they could be used for, other than string cheese or beef jerky. Cleaning them would be a nightmare - I could not even get my fingers all the way into these enclosures. What were the designers thinking?
Others have complicated drawers and shelving, designed for "convenience" but rather fragile and fussy. Our current fridge has a slide-out drawer that uses a cam-and-gear mechanism to life the drawer lid as you slide it out. A friend of ours has the same fridge and they broke the lid by forcing it. With the cost of parts, they ended up buying a new fridge! (One reason we are thinking of replacing our current fridge with the same model is that all the shelves and drawers and such would fit - and we would definitely save those - replacement parts like this are obscenely expensive!).
But, for the meantime, we will limit our appliance shopping to the microwave department. It's actually broken (not working) and really all we need. Since I dried out the membrane switch panel in the fridge with the hair dryer, the damn thing seems to be working perfectly - so far. But the writing is on the wall, and eventually we will have to replace these appliances. It will not be an "unexpected repair" as so many people claim happen in their lives, when in fact, these things are quite predictable!
