As we discuss here, new appliances unfortunately aren’t designed to last for decades. Knowing this, what do you do if, say, your seven-year-old dryer stops working and you get an estimate of $300 to repair it? Do you fix it or buy a new one?

Several websites provide repair-or-replace decision tools, but because these calculators rely on average product lifespans, they sometimes spit out misleading advice.

For example, let’s say the average lifespan for your dryer is around 10 years. Why spend $300 to repair it to get only three more years of work out of it when a new comparable dryer costs $800?

First, lifespan numbers are averages. If your appliance is already seven years old, and hasn’t had a previous breakdown, it means it probably doesn’t have major design flaws and after a repair is likely to last longer than 10 years total. Small households that use appliances lightly can expect longer-than-average lifespans. And because lifespans of appliance models are all over the map, a well-built appliance with few fancy controls might last much longer than its less durable, more high-tech counterparts.

Second, many owners replace old appliances with new units because they want different features, a new color, or another size; don’t want to move it to a new house; or want to get rid of the machine for reasons unrelated to durability. Some might even be jettisoned because owners misuse published lifespans to prematurely condemn their appliances to the junk heap. If you are happy with your dryer, and there are no signs of rust or other visible flaws, these factors are irrelevant.

Also, just because one element of your appliance breaks doesn’t necessarily mean others will fail. Things fall apart, even on brand-new appliances. A model with no visible damage besides the issue you are fixing might last many years without other problems—and the next problem also might require only a reasonably priced repair. Many major appliances, including relatively inexpensive models—which may cost less because they have few extra (and failure-prone) controls—keep drying, washing, or chilling for years.

If you are considering replacing an appliance as a bulwark against future breakdowns, remember that appliance problems are generally inconvenient, not disastrous. The worst possible catastrophe is flooding caused by the failure of a clothes washer’s supply hoses or a dishwasher’s shut-off valve (see page 64), and those are very unlikely.

There are, of course, good reasons for replacing broken appliances. You might like the features and looks of new appliances—a washer or dishwasher that operates more quietly, a fancy range with induction heat, or a refrigerator with more storage capacity.

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