David W Poway , CA August 18, 2014 Appliance: Jenn-Air Refrigerator JCD2289ATW Jenn-Air Refrigerator Jcd2289atw: Every three to four weeks the coils in the freezer would frost over and the refrigerator wouldn't cool properly also we began hearing a buzzing sound in the top right of the refrigerator side. How to replace Defrost Control Board. I first replaced the Defrost Heater Assembly. This took about an hour (much of the time was spent defrosting the coils with a hair dryer). When I took out the existing heating element, I found that it was corroded through. After replacing the heating element, the coils frosted over again and the buzzing sound started happening intermittently. Then I replaced the Defrost Control Board. This was a fifteen minute job with the help of Youtube videos. I haven't heard the buzzing since then and the jury is still out on whether this will fix the problem with the coils freezing over. 3 People found this story helpful Do-It-Yourself Rating: Repair Time Estimate: 15-30 minutes