I like our modern front-load washer for many reasons. For one thing, the gentle action and large capacity means our camping gear, from tents to sleeping bags, will not get a lot of extra wear and tear in the laundry. I also like the warp-speed spin action, as it means things we dry in the dryer take less energy, and the things we dry on the clothes line dry quickly. All this comes with a cost in that an electronics module is required for motor speed control in lieu of the old-school mechanical timer.
I had a nagging problem with bad connections that I thought was due to fretting on the connectors (fretting is an oxide buildup due to vibration of a connection). The Internet was more than helpful in identifying the fretting issue specific to this washer, and I spent a good deal of time plugging and unplugging card edge connectors every few days to resolve the problem.
It was not until I took the top off and I had the door relay kick on that I noticed a curious flash near the circuit board. I then discovered a telltale spray of oxide and soot on the inside of the plastic housing underneath the circuit board where the relay resides. It was clear once I removed the circuit board that poor solder joints for the relay had finally gone from intermittent to hard failure. The connector tabs were outlined with a dark fracture in the solder joint.
I suspect the poor solder joints stem from early attempts at RoHS compliance. With a little work with a soldering iron, I repaired the connections for good, or at least the last two years. I can accept that, in lieu of the twice-a-week disassembly and jiggling connectors, with mixed success. While I was there, I retinned the card edge connectors to address fretting issues, just in case.
The lesson learned in this case is that there is still an amazing amount of electronics problems that can be identified by careful visual examination, with no test equipment required.
I still love front-load washers for their economy and performance, and now I have one that performs as it should.
This entry was submitted by Ken Lillemo and edited by Rob Spiegel.
Ken Lillemo has worked for the last 26 years as a process engineer in a low-pressure lab.
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