Ron H Tempe , AZ December 21, 2015 Appliance: Model 790.90219013 Dr code no heat Replaced the clock/timer control board. An overlay is a must, unless you want to remove the circuit boards from the plastic housing and snap them into the old plastic housing. I didn't order the overlay and had to transfer the new circuit boards to the old housing with the overlay already in place. The part should have an overlay with it. Nothing but success with the repair job. Do-It-Yourself Rating: Repair Time Estimate: 30-60 minutes