Jim, I wonder if the company is aware of this problem. Did you or your friend contact the company about this problem and solution? If they don't know then this may give them a reason to issue some kind of repair or recall options for owners.
It's scary how many manufacturers don't pay enough attention to all of the design considerations that go along with optimizing a product for its environment. This was a nice find, as noted, but a real bogus oversight on the part of the manufacturer. That kind of testing, especially given what the dehumidifier is supposed to do, isn't rocket science--just common design sense. A simple, cost-effective choice of another type of material for the push buttons would have been all that was necessary to avoid any issues.
I worked for a company that made agricultural electronics. We quickly found that it's very difficult to manufacture a membrane switch that's reliable in an outdoor environment. We went through several vendors before finding one that could manufacture a robust switch. Most of the problems were from silver migration, where the silver trace in the switch panel migrates to an adjacent trace. Not surprisingly, a more robust switch also cost a little more money.
Since the problem with the humidifier was caused by a switch making marginal contact I wonder if the pull-up resistor was too stiff to work properly as the product aged?
It is interesting how many companies make mistakes like this. It reminds me of the old 1960s British sports cars I had. They were really fun, but terriably unreliable. The engines were relatively heavy and overdesigned. They would last forever. It was always some switch or small part that would break. We joked that these were designed by their new engineers.
Good question, Nadine. Even so, I would think manufacturers should test their products in consumer applications before sending then off into the consumer world. The last place they want to find out about problems is from their customers.
As an exercise in "discovery" & satisfaction for the more experienced among us, it would be interesting to find out WHO the manufacturer of this dehumidifier was, and get more info on the design team. IF the "chief engineer" of this company has an advanced degree from one of our prestigious business schools (think M.B.A. here!!), then it's no wonder that the switch design was marginal from the outset. Experienced engineers would have nixed using a pad switch w/ silver contacts, instead opting for a tad more expensive gold contact, which exhibits no oxidation properties. And, IF the engineers were recent grads, with little real world experience, the silver oxidation & migration phenomenon would have been alien to them.
When I went shopping for a dehumidifier several years ago, I of course looked at the cheaper ones first, which are aimed at consumers. Although they're a lot prettier than the industrial versions, they just didn't look serious: I live in a rainforest and I wanted to buy something that really works here. So I passed those by. The only electronics in my $900 portable, rollaround, commercial-grade industrial-strength, ugly gray metal Ebac dehumidifier are probably a few sensors and the LED "full" light on the front panel. More germane to this story, the only front-panel control is a mechanical rotary dial to indicate what percentage humidity I want it to keep. Although we've had to open it up and clean out the air filter every couple of years, it's been a workhorse and well worth the investment.
Anne, we had one of those non-electronic dehumidifiers and ours put in 10 years in one basement and another 20 in our Massachusetts house. It had one dial that went from OFF through LOW (humidity) to HIGH. The coils filled up with dust and required a thorough yearly cleaning with an outdoor hose, but otherwise the dehumidifier kept running and running and running. We left it for the buyer when we moved to Utah where we have no humidity problems.
Now that people note problems with small disc switches on front panels, I wonder how long our washing machine and dishwasher will last. I can't think of more humid operating environments. Perhaps the manufacturers used gold contacts.
Nadine, in most of the cases the best part is it may be only a minor or silly faults. But in a fast life mode, nobody has the time to just check atleast the basic things before calling a service person.
For 3D printing to make the jump from rapid prototyping to manufacturing, engineers will need to find easier ways to move products from their CAD screens to their printers.
Gigabit and PoE are two networking technologies moving ahead in tandem as industrial users power remote Ethernet devices such as IP security cameras at 1,000 Mbps over existing CAT5 cable.
New versions of BASF's Ecovio line are both compostable and designed for either injection molding or thermoforming. These combinations are becoming more common for the single-use bioplastics used in food service and food packaging applications, but are still not widely available.
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