Electronic Controls, Bad Rap?

[kb0nes]

It seems that I often read here on the forums about the undesirability of electronic controls as opposed to mechanical timers etc. But is it really the electronics that deserve the blame? Surely we can all admit that computer control can add some advantageous options to an appliance.

Properly designed and constructed electronic controls _should be_ far more reliable then anything mechanical in the long term. Solid state electronics don't wear out but they can be damaged by impulses etc if they aren't engineered correctly. Note I'm not saying that current appliance controls are properly designed...

Today the case is often that costs have been slashed and quality has been cut to meet the target price. I believe cost cutting and poor design will also effect mechanical timers too. Will a mechanical timer made today still be hauling-the-mail in 50 years?? I don't think today's mechanicals will be as durable and overbuilt as those of the past. And its not a fault of the timer being mechanical, its that quality costs money and people don't buy for quality these days.

With any appliance made today the control(s), be they electronic or mechanical, will likely be unavailable in 10-15 years. Perhaps some NOS parts will be available but control failure may doom the machine.

I have a suspicion that mechanical timers built today will likely prove less easily serviceable then ones made in the past. In order to make things more inexpensively, assemblies are crimped, welded or bonded together. Using screws crews cost money and increases failures. While electronic controls do use components that are either proprietary or may have short End of Life availability, many of the components that fail an electronic control can be substituted with a different part to get the control running again. My opinion is that the electronic boards may be more repairable then a mechanical timer on down the road.

To a large extent the considered non-repair ability and fear of electronics is due to the fact that electronic technology is not as well understood by many repair people. For most of us the mechanical parts are easy to see and figure out, electronics are more of a "black art". It reminds me a lot of how automotive mechanics took to fuel injection. Fuel injection is easier to diagnose and repair then a carburetor, you can do tests and actually isolate the failed part. A carburetor has to be torn down and rebuilt with the hope (fingers crossed) that the problem was fixed. Personally I'd much rather repair a FI system then a carburetor. For full disclosure my opinion of electronics is somewhat biased by having a background in the electronics field.

I only throw this out there to offer a different viewpoint on current controls available in modern machines. I really believe that it is the cost cutting that will cause today's machines to be less long lived then their predecessors. This may spark some lively discussion, now where did I put my asbestos underwear??

 

[whirlcool]

Our 1993 Whirlpool set has electronic controls and has never had a problem with them.
But then again they have always been used in an indoor laundry room. If they were in a laundry area in a garage, I don't know how long they would last due to the heat and humidity that's out there.

 

[retropia]

The light switch on our over-the-range Whirlpool microwave stopped functioning a few years after we bought it. The light would stay on continuously, so we took out the bulb. The switch is part of an electronic touch pad, and so to fix the light switch, I'd have to replace the entire touch pad. If I remember correctly, the part alone was somewhere near $150, plus labor on top of it. It would be nice to have the light and switch functioning, as we used it a lot.

If it was just a mechanical slide switch, I'd have to believe it wouldn't cost so much to fix it. As it is, it is not cost-effective to replace the entire touch pad. So we're waiting for something else major to go wrong so we can send the entire unit off to be recycled. It is wasteful, but that is the way it seems to go with modern electronics.

Probably from the manufacturer's point of view, it costs less to include all of the switches in a touch pad instead of having individual switches that can be replaced.

(As an aside, John L/Combo 52 said that the light switch failing is not uncommon on these microwave touch pads; I believe he said it is due to a power surge.)

 

[arbilab]

Electronics 'may be more repairable' but for the average buyer calling the average repairman the skill does not exist. Trouble with electronics in appliances seems they are under-engineered for the conditions, as above, heat and moisture. Another is that the marginal electronics are connected with no protection to marginal assemblies like wax motors, so when the assembly fails it kills the board.

Electronics also tend to be grossly overpriced for what they are. The board, components and fab -- all done in China -- can't possibly cost more than $20 and can't possibly be bought for under 5 times that. Electronic appliance boards are an engineered profit center for the vendor. They're designed to fail under any but optimal conditions, and the pricing is piracy.

Other than my 1982 GE microwave I don't own any electronic appliances, and I don't want to.

 

[washer111]

Good Point:

You make a good point - if electronics were actually built properly, and manufacturers didn't just cheap out and run high current applications through cheap circuitboards, then I'll bet that anything digital would be more reliable for sure! However, this is not the case. Most washers/dishwashers/dryers run heating power, motor power etc through the control board, rather than via a relay, which puts huge stress on the circuitry - this causes premature failure. I believe the same problem caused issues on the older Chevrolet Caprices (see link below) - where high current for the blower motor (A/C system) was run through the controls, which eventually burnt them out, or started a fire. 

 

Although mechanical stuff has the similar design flaws and electrical routing issues - even KitchenAid did it on their dishwashers, as another thread highlighted. The timers on those were obviously over-engineered, otherwise they too would've bit the dust long ago. 

 

If all of this were addressed, you may actually see modern appliance that would run for longer - although poor resistance against heat and humidity would certainly get the better of them eventually. Our old washer (and our neighbours identical set) was cheap enough that when on a Hot wash, steam billowing out of the back of the lid (next to the digital controls) would condense all over the control panel, and likely enter the un-protected area behind the panel - wreaking havoc. Our washer never got this treatment: It was used on Cold water only (hahaha!) Next doors, is more unfortunate. However, in the 3+ years its been there, it hasn't broken down - whilst ours needed a recall kit (although ours was a genuine HE machine, with auto water level and a "Freeze for 5" cycle - that one had manual water level and spins rinses, but no recirculation or any other HE BS to cause trouble). 

 

[frigilux]

Things like car, jets and space shuttles are full of electronics and they are subjected to far more extreme conditions than those in a washer or dishwasher. As others have stated, the problem is the inferior quality of electronics used in home appliances. The cheap stuff has proved itself unable to handle vibration, heat, or humid/moist conditions. The board on my circa 2004 Frigidaire dishwasher had to be replaced three times in two years due to failures. The board on Smokey The Maytag (which replaced the Frigidaire) malfunctioned and caused the heating element to operate for hours at a time while the machine was off and nearly caught fire. 

 

I agree:  It's not electronics per se that suck.  The problem is the inferior quality of the electronics being used in consumer goods.

 

[DirectDriveDave]

What I love about the mechanical timers is that they tell you exactly how far along something is, whether it be a washer or dishwasher. Now, some electronics did have a "time remaining" which was good, but more often than not, I saw that they didn't have something like that.

Also, in the unlikely event that there is a power failure, and then (hopefully soon) comes back, it will resume right where it left off, you can also, if you need to, turn washer timers to the beginning of a cycle again, if you think you need more wash time, and when you either push in a knob or turn it to off it is fully OFF; no standby.

 

[DADoES]

 
A large drawback of electronics IMO is integration.  For example, a single control board runs everything on a double wall oven, resulting in BOTH ovens being inoperable when the board fails.  One oven is still usable if the other's electro-mechanical thermostat or selector switch fails.

 

[combo52]

Electronic Major Appliance Controls

Good thread topic Phil, problems with poor durability and expensive to repair electronic controls on appliances are a daily problem for us repair guys and you are very correct it should not be this way. We have the technology to build controls that would almost NEVER fail in the life of most home appliances. But manufacturers have usually taken the cheap way and have not had a strong desire to keep appliances out in the field repairable in many cases in barely 10 years.

 

Cheap membrane touch controls may make sense on $100 microwave ovens, but my objection comes in when they use the same level of construction on $1000, 2000, 3000 and up to nearly 10,000 dollar appliances that are built-in to your kitchens and laundry rooms.

 

Touch Membrane controls are very poor at best for durability, notice they are not used on cars, your computer and probably are unheard of in military equipment, LOL.

 

  Phil the guy who started this thread is my younger brother and I think we should also see if we could get one of our older brothers  [ Jerry ] to write something in this thread. Jerry is a Quality Control engineer with expertise in the electronics field. I know that I have certainly learned lots from all four of my brothers and Mother and Father as we are a very technical family, we always have plenty to talk about at dinner, LOL.

 

I do see some signs of progress in the major home appliance industry and electronics are certainly here to stay, consumers should keep up the pressure on manufacturers when they have problems and hopefully there will be more competition among manufacturers to build the best and most reliable product again. Some of you may remember the quality moves by most appliance manufacturers starting in the 60s and continuing through the 70s that were done in response to the many serious problems that major appliances had in the 50s 60s and 70s. Unfortunately by the time every thing was rolling along in the 80s and as reliability had improved so much the emphasis on building the most reliable appliance was put on the back burner. I do predict it will become a bigger issue sometime in the near future if enough consumers complain, CRs could help lead the way but I think they have lost much of their original mission of helping protect consumers from poor quality appliances. John

 

[kb0nes]

Humidity and Heat

In most cases solid state electronics should be very impervious to both humidity and heat, provided it is within reason. As long as the components aren't too hot to touch, they will be fine. I have serviced a few solid state amplifiers that have melted to solder on the transistor pads, 60/40 solder melts at ~360 Deg F... The amps I repaired lived for years after the cooling issues were cured!

Humidity can cause horrible damage due to corrosion. Connectors and contacts, especially those with dissimilar metals can be problematic. Years ago we had a TOL Whirlpool dishwasher that was one of the early units with an electronic control. The card edge connector would corrode badly due to steam and condensation. The fingers on the board were soldered when it went through the wave solder machine. Several times I had to reflow the solder on the fingers and clean the connector to get the unit to run. I believe that John used to cut off the connector and actually solder the wires to the pads!! Ultimately I used a DeOxit grease from Caig Labs to eliminate the corrosion problem. A buddy of mine took that machine and it is still running today.

Solid state electronics can be sensitive to overloads and impulses (surges) but good design will remove those risks. I find that many problems are blamed on surges and a lot of surge protectors are sold this way, the problem is likely blown out of proportion though.

One example of how amazingly durable solid state electronics can be is the Voyager I spacecraft that was launched in 1977. 36 years later, after enduring a the stresses of launch and a lifetime of cold, we are still hearing from it as it is poised to leave our solar system. Of course the design cost of the space craft electronics and one of our modern FL washers is just slightly different...

 

[alr2903]

Interesting thread the Apollo moon missions IIRC were controlled with electronics, that were slow and primitive by todays standards. The stakes were higher than a load of dishes or laundry. Are controls in modern appliances just overly complicated? Will we ever see a modern F/L with the basic 3 cycles of the past (Normal, PP, Delicate). I really do not need controls that read like an Excel Spread sheet. While we are at it lets get the print/displays large enough to not need reading glasses. It is a household chore not a missile launch. alr

 

[kb0nes]

Complexity

Alr,

You raise a good point here with issues of complexity. One advantage of electronic control of a machine is that cycles are now just software. Anything the developer can dream up can be reality for more or less no extra cost. I like to call it "feature creep" they just keep adding and adding till the typical user is overwhelmed. Adding a cycle in a mechanical timer requires an entire redesign of the timer and is expensive, especially if the number of units sold is limited. Hopefully they at least can keep the user interface semi-intuitive or they will just cause problems for themselves.

Of course our desire for complexity (or not) is highly personal. I have been considering a Huebsch commercial softmount front loader. They have an electronic control where the user can fully control the cycles for time, temp, speed, added rinses etc. Might take a while to figure it all out. But the versatility would be awesome! So would be the 9kw sump heater, Powerrrr! It reminds me a bit of Robert's PC controlled washer.

Indeed aerospace electronics are robust, even those back in the 50's & 60's when solid state was still in its infancy and suffering from early development and fragility. They simply engineered VERY conservatively and with lots of redundancy for safety. The fact that Apollo 13 made it back after all it had to endure was testament to care they took in the design. Of course all that cost a lot of money and that surely won't happen in the commercial market.

 

[tolivac]

Another factor on Apollo and other space missions and critcal electronic applications-is back up systems in case the primary one failed.This has happened on the space flights-the control system had to go to back ups.That is why they are there.Now to design a home appliance that way-premium electronics with back ups-would indeed,be just too expensive for average Joe the buyer.And also----some of those space trips used VACUUM TUBED electronics.Esp the radio transmitters.Even Apollo had tubed transmitters.Eimac made the tubes.Remember there are VAST diffrences between critcal grade electronics-solid state or tube as opposed to consumer electronics.In the critical grades-premium grade semiconductors and tubes,as well as other parts are used-even the circuit boards!Circuit boards and parts were treated with fungicides and imprgenated with epoxy to keep moisture out of the boards and parts.

 

[qualin]

One of the reasons why electronic controls have a bad rap is due to the poor quality and engineering which went into designing them. We can blame the bean counters for this, only because it can have the possibility of adding a lot of cost to something.

A lot of people don't know that there are different grades and tolerances of electronic components. To save a few bucks, the manufacturers sometimes use low grade components with large tolerances.

Case in point, a "budget" 330 ohm resistor can have a variance as much as 5 percent, which means it could have a resistance between 313.5 ohms to 346.5 ohms. Whereas, a more expensive resistor with a 1 percent tolerance will have a resistance between 326.7 and 333.3 ohms.

Now, in a batch of 100,000 resistors with a 5 percent tolerance, a lot of them could be very close to 330 ohms, but there's a chance some of them may not be.

Now, the problem is, when you have a component which is slightly out of whack like that, it can degrade the lifespan of the other components on the circuit board, requiring repair or eventual replacement. However, we're still talking about a few short years after the board has left the QA control department.

Unfortunately, manufacturers really don't have any incentive to make the electronics last past the warranty period.

This is why Military spec components have to meet very rigorous quality control. A 5 percent resistor would never be found in milspec equipment. When there are matters of life and death involved, they can't afford to have electronics fail.

Built properly, electronics can outlast anything mechanical. At least IMHO. In saying that though, this is barring things like lightening strikes, etc.

The big move into electronics is because mechanical timers are limited as to what they can do. Whereas, a Microcontroller can do anything and everything imaginable.

The benefits outweigh any drawbacks...

 

[thefixer]

It's really sad that companys are putting out such crap. The new (3 years) Whirlpool VMW top load design which is everywhere being sold under various brand names and model numbers is a total piece of crap. The control board being one of the many failure items. Prices have recently increased on repair parts for these washers with the control board now running $275-$375! With the cost of the board after markup and the tech service fee, you can buy a new washer. What a joke. And now your 2-3 year old washer is ending up in the landfill or getting recycled.

Nobody is going to be repairing these boards. The average tech has very limited knowledge in basic electrical troubleshooting skills let alone repairing electronic circuit boards. Not that Whirlpool is going to provide the schematics anyway. Iv'e been an electronic service technician for 37 years doing component level repairs. It has been increasingly difficult to do board repairs because of the small parts, density of part layout and specialized equipment required to replace parts. It's a dying art and not cost effective nowadays. It's a downhill slide as long as we keep buying chinese made junk. Not much is made to last anymore.

Eric

 

[qualin]

There is something to be said for purchasing something which can still be serviced.

Even though a lot of us probably couldn't repair a mechanical timer, it certainly looks easy to replace one.

I guess that's really the only problem I have with electronic boards going bad, the price of replacement.

 

[optima]

Electronic Controls

Quite simple Mechanical controlled. Totally hate todays eletronicaly controlled washers.

 

[philcobendixduo]

Electronic controls are fine if well engineered

My 1987 Kenmore "Limited Edition Electronic Fabric Care" washer and dryer are still going strong with never a problem with the electronic controls even with all the heat, moisture and vibration associated with the operation of washers and dryers.

My 1994 Maytag dishwasher - the same. No problems with the electronic controls.

My 1987 GE Spacemaker over the the range microwave - no issues with electronic controls.

I know from what I've read online that many of todays electronic controls are "under engineered" and use "cheap" parts that don't last. One would think that with the advances in computers and electronics, today's controls would be MORE reliable but such is not the case. Very sad.

 

[juan0069]

Membrane Keyboards

Sorry combo52, but nearly all modern computer keyboards are of the "membrane" design... True, they use a key with a plunger to press on the membrane instead of your finger, but still, same design under the keys.