The Frigidaire Defrost Heater is an OEM replacement part compatible with select Frigidaire brand refrigerators. This part is designed to maintain optimal freezer temperature and prevent frost buildup.  Symptoms of a bad part: • Excessive frost buildup in the freezer • Freezer not cooling properly • Loud clicking or buzzing noises Causes of a bad part: • Age and wear and tear • Power surge or electrical issues • Dirty or clogged condenser coils • Malfunctioning thermostat This defrost heater is also compatible with Electrolux, Gibson, Kelvinator, and Kenmore refrigerators.242044021 (AP4561026) replaces 1614858, 241940103, 242044009, AH2581595, EA2581595, PS2581595.