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Comment by chrisseaton | Hacker News Reader

Why's mechanical better? Mechanics stick, break, become worn out. A circuit generally doesn't, does it? I know capacitors burst but they're easy enough to change. Do components like ICs ever just stop working? I would have thought solid-state would be better for endurance.

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For some functions, such as simple timers, one advantage mechanical might have is that it might be easier or cheaper to obtain repair parts.

A mechanical timer is likely to be a commodity part used by many different manufacturers in a variety of products.

An electronic timer is more likely to be a custom board designed by the manufacturer of the appliance you are trying to repair, possibly designed specifically for that model. There might be only one source for replacements, and they may be restricted to "authorized" service companies.

Yes, ICs age. Fissures in the subtrate expand with each thermal cycle. Delamination is a similar effect. That's how manufacturers prematurely age their parts -- by endless cycles in the oven.

The biggest culprit is flash memory. It's in almost everything, and has a much shorter life than the 10 years most manufacturers claim.

touch pads have high failure rates. if they don't go, the control board does. and if neither, the connection between them.

as for easy to change, replacing the mother board on my refrigerator would cost 600$ without installation fees. guess who bought a new refrigerator? :(

I know it happens, but how does a mother board just die? I mean it's a piece of plastic with durable metal channels on it. The channels don't wear or burn out. Everything's just inert. I know some components like capacitors do die, but they can be tested and replaced. How can a mother board just stop working?

1. Corrosion 2. Electrolytic caps. 3. Vibration. 4. Flexing due to thermal cycling. 5. Electronic designs operating near their limits, resulting in increased failure rates.

It used to be everything in a hostile environment (hot/wet/corrosive) was potted (dipped in epoxy) and in an enclosure. Now they have bare boards. Electronically controlled motors and very limited protection circuitry for the ICs. Just not built to last. No commonality in circuit boards so parts are very expensive (possibly by design; they only need parts for warranty repairs, after that they don't care about cost/availability).

some kind of short? kitchens are damp places, the door is opened and closed many times a day, huge power fluctuations, etc. I dont know why for certain, its not my field. I do know that it happens a lot, as I started googling what could be wrong with my fridge when it went haywire.

as for touch pads, contacts fail all the time.

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