(MONEY Magazine) – My friend Susan believes that repair people are the most powerful folks on the planet. No one else, she argues, can tell you that they'll show up sometime between 8 a.m. and 1 p.m. and actually get away with it. And after a tussle with my dishwasher, I agree.

About three years ago, my husband and I bought a new KitchenAid. It was a middle-of-the-line model with few bells and whistles, but it was infinitely quieter than the 15-year-old Kitchen-Aid that it had replaced. We stuck with the brand because that 15-year run was impressive in and of itself.

About 18 months later it stopped draining. I figured that the warranty had expired, so I called our usual repairman. He fiddled around, got it working and charged me $100-plus for the visit. Three weeks later he was back. This time, he diagnosed, the problem was that we needed a new "computer." I didn't know that dishwashers had computers, but ours did and it was shot. We ate off paper plates for a few weeks while we waited for a new one. The bill: $200.

It lasted about two months. This time--before violating the rule of thumb that says you don't spend more to fix an appliance than half of what it would cost to replace it--I called the manufacturer's 800 number. They sent out an authorized serviceman (gratis) who confirmed that the problem was again the computer. Now I was cranky. I figured if the same part had gone twice, it could go a third time, and I had already spent enough days waiting for repairmen and eaten enough meals on Chinet. I wanted a new dishwasher. I called the 800 number again and again and again. At first my customer service rep told me there was no way the company could replace the machine, but finally the sheer volume of service calls I'd had won the day. "You went through so many repairs," she says,"that we said it would be better for us to replace it."

That was nine months ago. My new dishwasher is working just fine. But at the risk of jinxing it, I wondered what I could have done to solve my problem with less stress. Here's what I found.

CREATE A PAPER TRAIL For each new appliance, start a folder with the receipt, manual and warranty. Fill out the warranty card and return it to the manufacturer or register online. (I didn't because of the marketing that usually follows, but now I know you can opt out.) That way, you don't have to dig for make, model number and date of purchase if you have a problem--and the manufacturer can track problems specific to particular models and alert its technicians.

REREAD YOUR WARRANTY Although most comprehensive warranties last only a year or two, Tom Welke, v.p. of consumer care for KitchenAid, says pumps, motors, compressors and electronic components--like my computer--are often covered for up to five years. You can confirm at your manufacturer's 800 number or its website.

SEE IF YOU CAN FIX IT YOURSELF Unplug your appliance and then plug it in again to be sure the problem isn't, say, a fuse. If it's not, zip over to Repairclinic .com, where former technician Chris Hall has an impressive array of tools and diagrams to help you diagnose the problem and show you how to fix it. (He makes his money selling parts.) "In appliance repair, things have gotten more modular," he says. "That's made it a little easier to do yourself." If that looks too hard, go to the pros.

DEAL ONLY WITH CERTIFIED TECHNICIANS If you're under warranty (or the maker has offered to pick up the tab for the repair), the manufacturer can be directly billed only by its authorized technicians. Watch out here. After my usual (but unauthorized) repairman failed, I went to the Yellow Pages, looked up KitchenAid and booked an appointment with a guy listed there. Turns out, he wasn't authorized. So check out your manufacturer's website or call its 800 number to find a repairman near you. (The Association of Home Appliance Manufacturers lists 800 numbers at www.aham.org.)