Whirlpool washing machine l1961 | Forum for Electronics · Help Needed for Whirlpool Washing Machine SMPS board. Machine dead found two resistors burnt R20 and R21. R20 is 1/4W resistance completely burnt out. R21 appears to be 1W burnt. Not sure about the IC LNK304 and other parts. What is the value for R20 ? Need the schematic diagram or any help with the resistance values.