Samuel K Summit Point , WV April 06, 2016 Appliance: Whirlpool Refrigerator W4TXNWFWQ03 Whirlpool Refrigerator W4txnwfwq03 / : Freezer was icing over blocking port holes to the fridge section. How to replace Diffuser. I defrosted the freezer and replaced the defrost temperature switch on the cooling coils. I cut the wires and used two small wire nuts to complete the splices. I defrosted the freezer with a hair dryer, but you have to careful not to melt the thin plastic walls and bottom of the freezer. You only need a nut driver, wire cutter, and wire stripper and two small wire nuts, (not supplied with part). 3 People found this story helpful Do-It-Yourself Rating: Repair Time Estimate: 30-60 minutes