Sunday, December 06, 2009

Dishwasher Woes

A while back, we replaced our dishwasher, which came with the house when we bought it some fourteen years ago. The new one, selected on the basis of a positive online discussion of the previous model in the (Bosch) line, turned out to be in almost all ways worse than the old. It held fewer dishes, cleaned less well, dried much less well. It's only significant advantage, so far as we could see, was that it was quieter. It is bad enough so that we are considering simply throwing out our new dishwasher and replacing it with another, after doing a more thorough job of research.

It occurred to me to wonder whether part of the problem had to do with pressure, either from the market or from regulation, for energy efficiency. The external dimensions of a built-in dishwasher are fixed. One way of making it more energy efficient is by putting on more insulation to make it easier to keep things hot while they are being washed—which also makes it quieter. More insulation is likely to mean thicker insulation, which means less space for dishes. Along similar lines, the new dishwasher, unlike the old, doesn't have the option of hot air drying—dishes are dried (or not dried) only by the residual heat from the washing. That saves energy, but makes the dishwasher a good deal less useful.

Does anyone reading this know enough about dishwasher engineering to say whether new dishwashers are, typically, worse than old for these reasons? Whether, if so, the problem is energy efficiency standards set by regulation, or merely the advantage of being able to advertise energy efficiency and low noise?


Unknown said...

It's not just dishwashers. You find this with all appliances, especially washing machines and dryers.

We're currently using a 40-year-old Maytag washing machine in our house. Don't laugh... we got it for free and it works far better than the energy-efficient frontloader it replaced. Same with the dryer... replaced the energy-efficient one that came with the house with a fossil that we were given for free.

Both work better than the (decades newer) machines that they replaced. Both of the replaced machines died from complexity (extra features that we didn't need but added failure modes to the unit). Both of the replacement machines are noisier and probably use more power, but that's a tradeoff we're willing to make for effectiveness and longevity.

Our kitchen stove is probably almost as old. It has no electrical parts, just a gas line coming in and three pilot lights. It always works immediately and there's nothing to break. We expect it to continue working for a long time.

For the forseeable future, we'll be getting appliances from Craigslist, not Lowes/Sears/HomeDepot/Whatever.

RKN said...

I don't know enough to say if new machines are typically worse or not, or, if they are, for the reasons you mentioned. I would expect that like most consumer appliances one more often typically gets what they pay for.

We recently purchased a new home that came with an upgraded Asko dishwasher that performs much better in every respect compared to the older dishwasher (Maytag?) in our previous home, while using less energy and less water. Of course it cost significantly more than many other dishwashers.

Unknown said...

Ah, irony.

Our old washer/dryer set was an Asko. I bet yours is dead in 5 years.

We had it fixed a couple times, then finally listened to the repairman when they said we were wasting our money every time we fixed it. It just kept breaking.

dWj said...

My dishes dry pretty thoroughly from the residual heat, provided I open the dishwasher right away. This doesn't seem to me like something that would be hard to replicate through engineering -- to have a vent that would open and make sure dry air can get in after the cycle. Maybe it would be hard to make properly waterproof.

Mike Gogulski said...

What Micah said. And whatever you do, do not replace your toilets with anything made before 1995. Please, I beg you.

BobW said...

I think Mike Gogulski meant after 1995.

If you must get a new toilet, buy top-of-the-line recommended by Consumer Reports for flushing ability. (Though it's funny that they don't compare the latest toilets to the old standby.)

With all these efficiency regulations penny wise/pound foolish takes on new emphasis. said...

My Dishwasher (Miele) actually does vent air after it's finished. The dishes are always perfectly clean and dry. I'd by the same brand anytime.

I think one of the reasons why dishwasher capacity might have been reduced by the manufacturers is simply that average household sizes are smaller. I rarely even fill mine completely.

When I recently needed a clothes dryer I bought the most energy efficient one available. But one concern I had was not overloading the circuit it was on (which it shares with the washer). That it dries well, without overheating the room it's in is a nice bonus.

Stephen Dawson said...

A couple of years ago my kitchen taps self-destructed, so I purchased a new set. 'Water efficient' the proclaimed on the box, which stuck me as odd. I'm pretty sure that even with the old ones, everything that entered the tap on the in-pipe came out the nozel for 100% efficiency. What 'efficient' actually means was 'this tap will raise the cost of obtaining water, the cost being measured in user time.' They take about twice as long to fill the kettle as the old ones did.

My new toilet bowl is a true marvel of design. It is so efficiently designed that the entire contents of the bowl seem to be able to be replaced by the addition of very little more than the replaced volume in clean water.

Only problem is that the design results in a misalignment between the human anatomy and the drainage hole. To properly clear the waste, at least three flushes are required, or two with some manual scrubbing.

Douglas Knight said...

I think most people are willing to sacrifice capacity to quiet (cf, but not having a hot air option sounds like regulation, not advertising.

Robert S. Porter said...

I actually have found that the hot air drying function utterly useless and a waste of electricity, and thus, a waste of my money. I simply open the door and let it dry out naturally. I don't have a ton of experience with older dishwashers, but my cleaned just as well, if not better, than the old unit my parents used to have when I was a child.

David Friedman said...

"but not having a hot air option sounds like regulation, not advertising."

I don't think that can be correct, since many dishwashers do still have that option. As a general rule, with the old dishwasher, we used hot air drying in the winter, when additional heat is a benefit not a cost, but usually not in the summer.

Jan said...

As a German company, Bosch has to care about this:

So it might be a case of "regulated advertisement".

Anonymous said...

Unfortunately, many of the product review sites are more interested in rating the feel good greenness of products and not their ability to do the job they were designed for.

Take this Review:

Not so long ago you could count on most washers to get your clothes very clean. Not anymore. Our latest tests found huge performance differences among machines. Some left our stain-soaked swatches nearly as dirty as they were before washing. For best results, you’ll have to spend $900 or more.

What happened? As of January, the U.S. Department of Energy has required washers to use 21 percent less energy, a goal we wholeheartedly support. But our tests have found that traditional top-loaders, those with the familiar center-post agitators, are having a tough time wringing out those savings without sacrificing cleaning ability, the main reason you buy a washer.

Consumer Reports "wholeheartedly supports" a 4 fold increase in price for some feel good energy savings in washing machines.

As for dishwashers, buy a brand sold only in the US. I've worked on a few euro and assusie models and found them to be poorly engineered. Well, cleaning dishes wasn't the priority in the engineering.

Eric H said...

In the course of a bathroom refurb, I replaced the old toilet with a very new model after talking to some pros and looking at an older version of this. The new low-flo toilet has performed wonderfully, and a friend reports similar results with another brand. It turns out that there was a period in which toilet mfgs simply put a smaller tank on top of the old works, but since then they have revamped the tubes with the aid of comoputer aided modelling.

We just got a new front loader and so far it appears to work better. One of the ways it seems to help with energy efficiency is that it seems to spin dry much better, so that drying with the old dryer takes half as long. But I am very concerned about the complexity. Fixing older machines was usually a matter of inspection, but this new microprocessor has me worried about life cycle costs (and I'm a EE).This is about the only sense of planned obsolescence I accept.

So while some of your fears may be justified, it does seem that manufacturers can innovate their way out of a new set of constraints, but I believe that in the longer run the price we pay may not be performance, it may be lifecycle costs. But surely the planners didn't think there was a free lunch to be had, did they?

Unknown said...

How much energy is used building, selling, shipping, recycling new complex energy efficient appliances that last less than 5 years, compare to sticking with a less efficient but simple and reliable unit that's still working 10, maybe 20 years later?

Anonymous said...

$1400 on a new Dishwasher and it doesnt work nearly as well as the 20 year old $200 piece of crap that it replaced. Sure its quieter. Sure its more energy efficient. BUT how energy efficient is having to wash the dishes the dishes twice? How energy efficient is having to use 5 gallons of hot water to pre wash the dishes? This government regulation and interference is criminal.

They have spend MILLIONS of your dollars to try to figure this out. But then again, I guess there is more tax revenue on a $1400 dishwasher and extra detergents needed than a $300 one that actually works.

I guess there is more State revenue on the extra water used.

I GUARANTEE my "high efficiency" dishwasher and other appliances are causing me to use at least TWICE as much water, electricity and gas.

Their study shows how much energy is saved per cycle of the equipment NOT how much energy it takes to get the job done.

ABSOLUTELY rediculous