Ok. Ok. My clothes dryer isn’t, strictly speaking, a cycling component, BUT I think you can read the following and just substitute <mechanical derailleur of your choosing> where I reference my dryer. The experience and effect are the same, as are the streams of profanity they elicit from my normally chaste mouth (That last part’s a goddamned lie).
First, let me say that the Bosch WTVC3500UC/10 has done a fine job for about a decade. It is reasonably well made, and given the amount of miles (see what I did there) my family has put on it, nothing I’m about to say should be construed as a negative comment on the worth of the appliance for its intended purpose.
Like a rear derailleur which refuses to stop slipping a gear no matter how tension is adjusted or limited, the WTVC3500UC/10 is a simple machine, not that hard to understand, even for a dullard like myself. An electric motor turns the drum. Gas is ignited at the mouth of a basic duct, which then blows hot air into the drum case and through its fine perforations, the product of which is then vented out the back, down another duct and out into the open air, so that my neighbors receive olfactory clues that I do, in fact, occasionally wash my underpants.
When the WTVC3500UC/10 stopped heating the air coursing through its innards, I was immediately drawn to two parts affixed to its hot air duct, because there just aren’t that many reasons it would stop heating the air. Similarly, my rear derailleur lives in balance between its taut cable, a spring or two, and a pair of limiter screws. Like the dryer, it is a dynamic device, but not that complicated.
The most likely culprit, the butler of this inchoate mystery if you will, was the “high temperature limiter” (Part #00422273 if you’re playing along at home). It appeared as I squinted down the barrel of the gas igniter that something was detecting the heat generated thereby and then shutting it down after a brief and cursory period. A defective temperature sensor I figured, would be just the sort of character to abort the process in this fashion. The sensor, in our shambling metaphor, is akin to the derailleur cable, off tension by a few threads of a barrel adjuster perhaps.
For $30 + shipping, it seemed, I could find out if my hunch was correct, and so I ordered the part. This is where my dryer and derailleur diverge, for while it can be difficult for a slobbering ape like me to properly adjust a derailleur, replacing the temperature sensor in my dryer was another kind of ordeal. Despite fully removing the top and back of the dryer housing, the location of the aforementioned sensor and the fact that it was riveted to the side of the heat duct, made its replacement something like performing a molar extraction in my own mouth. My hands didn’t fit, I couldn’t see what I was doing, and in the end it’s was all I could do to pry the thing out, peripheral damage be damned.
It bears saying that even getting the limited access I achieved meant removing roughly 30 T18 Torx screws, and you know what happens when you put that many small screws in my immediate vicinity.
Installing the new sensor on the old rivets wasn’t going to happen, so I heat taped it in place and reconnected its wires, then spun the dryer back around, reconnected the gas and fired it up to confirm the fix. This is like that moment your gears spin freely in your work stand and you drag the bike outside for a quick spin down the street to verify your mechanical aptitude. (Wait…is this foreshadowing….because it feels an awful lot like…).
No dice. The drum spun, the igniter ignited, but again, within seconds an audible click shut the heat off again. Spiritually, I am out in the road, my chain spluttering over the cassette, hiccupping like a four-year-old who gulped his first soda too quickly.
I had been so sure that would fix it (That’s a blatant lie, I’m not an appliance repairperson).
For those holding a small Phillips head and trying to remember which screw is which limiter, you might guess the issue is not cable tension, but maybe instead you need to adjust the set screw at the back of the derailleur. In your mind, you know this not the actual solution, but you mess with it anyway, because you lack the patience to go methodically through the correct steps again. You’re me. I’m you. Life as we know it is just a simulation.
The WTVC3500UC/10 also has a flame detection sensor, affixed to the other side of the duct in an even less reachable location than the high temp limiter. Quite why this dryer needs a high temp sensor AND a flame sensor, I don’t know, but the internet thinks, if the problem ain’t one, it’s the other. This is only logical, if only logic were a thing in this simulation.
A good mechanic will tell you there is no bicycle adjustment that requires a hammer. That’s just information. Do with it what you will. If you use the hammer, as I have occasionally, there is no shame in it, but there ARE dents.
Look, here is, for me, the bottom line. I would never take a bicycle and throw it in a dumpster, because I couldn’t get the rear derailleur dialed-in properly. That would be a tremendous waste of a valuable and expensive thing, not to mention an uncool contribution to an already bloated landfill. I have thought about it though. I have also thought about giving up cycling altogether.
Unlike me, the WTVC3500UC/10 still does not blow hot air, but despite the parlous state of my sanity and the impatience of my wife, I have a real hard time thinking I’m going to replace it with a new one to the tune of $700, not when there’s another $30 sensor to replace (screw to turn) and the machine remains so simple and straightforward to repair.