Refrigerator Freezing Up or Not Defrosting? Defrost Limit Thermostat 5303918638 – Fix Frost Buildup & Restore Proper Defrost Fast

If your Frigidaire refrigerator has heavy frost buildup on the evaporator coils, the freezer is icing over completely, or the fridge is warm because airflow is blocked by ice, the defrost limit thermostat is one of the most common causes. In most Frigidaire top-freezer refrigerators, the defrost limit thermostat acts as a safety cutoff for the defrost heater — it monitors coil temperature and shuts off the heater once the coils reach the correct defrost temperature. When it fails open, the heater never activates and frost accumulates unchecked. When it fails closed, the heater runs too long and can damage the coils. ⚡ Common failure point in Frigidaire FFHT, FFTR, FGHT, and FFHI series refrigerators across multiple production years. Part 5303918638 is the genuine OEM replacement that restores proper defrost cycle control and prevents runaway frost accumulation.

❓ Is This the Right Part?

This is the correct fix if ALL of the following are true:

• ✔ Refrigerator powers on and compressor runs normally
• ✔ Defrost heater is intact (test with a multimeter — should show continuity)
• ✔ Defrost timer or control board is functioning (initiating defrost cycles)
• ✔ ONLY problem is frost accumulating on evaporator coils between defrost cycles, or heater not activating during defrost

Not sure? Send us your model number — we'll confirm before you order.

🔧 Common Symptoms

• Heavy frost or solid ice buildup on the back wall of the freezer compartment
• Refrigerator warm — evaporator coils completely blocked by ice, stopping airflow
• Defrost heater does not activate during the defrost cycle
• Refrigerator cools normally after manually defrosting, but frosts up again within days
• E or F error codes related to defrost system on the control panel

✔ If these symptoms match, this is the most likely failed component in the defrost system.

✔ In most cases, replacing this thermostat restores normal defrost cycling and prevents frost from returning.

📦 Part Details

• Part Number: 5303918638
• Type: Refrigerator Defrost Limit Thermostat — OEM Frigidaire replacement
• Replaces: 242303205, 242303201
• Brands: Frigidaire, Electrolux, Kenmore (Frigidaire-built)
• Compatible Series: FFHT1514, FFHT1614, FFHT1621, FFHT1814, FFHT1821, FFHT1831, FFHI1831, FFTR1514, FFTR1614, FFTR1621, FFTR1814, FFTR1821, FGHT1835, FGHT1846, FGHI1865, FPHT1897, CRT151, CRT181, CRT182, CRT186

⚙️ Installation

Skill Level: MODERATE — 30–45 minutes. Disconnect power before servicing. Remove freezer contents, shelving, and the rear evaporator panel (4–6 screws). Locate the defrost limit thermostat clipped to the evaporator coil — disconnect the two wire leads, unclip the old thermostat, and clip the new one onto the same coil location. Reconnect the leads (polarity does not matter), reassemble the panel, and restore power. Run a manual defrost cycle to confirm the heater activates and shuts off correctly.

✓ Compatible Models

Confirmed compatible with 25360002412, 25360002413, 25360002414, 25360002415, 25360022413, 25360022414, 25360022415, 25360302413, 25360302414, 25360303413, 25360303414, 25360303415, 25360304413, 25360304414, 25360304415, 25360309413, 25360309414, 25360309415, 25360312412, 25360312413, 25360312414, 25360312415, 25360312416, 25360313412, 25360313413, 25360313414, 25360313415, 25360313416, 25360319412, 25360319413, 25360319414, 25360319415, 25360319416, 25360382411, 25360382412, 25360382413, 25360382414, 25360382415, 25360383411, 25360383412, 25360383413, 25360383414, 25360383415, 25360383416, 25360389411, 25360389412, 25360389413, 25360389414, 25360389415, 25360389416, 25360402413, 25360402414, 25360402415, 25360404413, 25360404414, 25360404415, 25360409413, 25360409414, 25360409415, 25360412412, 25360412413, 25360412415, 25360419412, 25360419413, 25360419414, 25360502413, 25360502414, 25360503413, 25360504413, 25360504414, 25360509413, 25360509414, 25360602414, 25360602415, 25360602416, 25360603414, 25360603415, 25360603416, 25360604414, 25360604415, 25360604416, 25360609414, 25360609415, 25360609416, 25370302413, 25370302414, 25370302415, 25370303413, 25370303414, 25370303415, 25370304413, 25370304414, 25370304415, 25370309413, 25370309414, 25370309415, 25370402413, 25370402414, 25370402415, 25370404413, 25370404414, 25370404415, 25370409413, 25370409414, 25370409415, 25370502413, 25370502414, 25370503413, 25370504413, 25370504414, 25370509413, 25370509414, 25370602414, 25370602415, 25370602416, 25370603414, 25370603415, 25370603416, 25370604414, 25370604415, 25370604416, 25370609414, 25370609415, 25370609416, CRT151QW3, CRT151QW4, CRT181QW2, CRT181QW3, CRT182HQB3, CRT182HQB4, CRT182HQW3, CRT182HQW4, CRT182IQB2, CRT182IQB3, CRT182IQW2, CRT182IQW3, CRT182SS0, CRT186QB3, CRT186QB4, CRT186QS1, CRT186QS2, CRT186QS3, CRT186QW3, CRT186QW4, CRTEH182TW0, FFHI1831QE4, FFHI1831QE5, FFHI1831QE6, FFHI1831QP4, FFHI1831QP5, FFHI1831QP6, FFHI1831QS4, FFHI1831QS5, FFHI1831QS6, FFHT1514QB2, FFHT1514QB3, FFHT1514QB4, FFHT1514QB5, FFHT1514QS2, FFHT1514QS3, FFHT1514QS4, FFHT1514QS5, FFHT1514QW2, FFHT1514QW3, FFHT1514QW4, FFHT1514QW5, FFHT1514QZ2, FFHT1514QZ3, FFHT1514TB0, FFHT1514TB1, FFHT1514TB2, FFHT1514TB3, FFHT1514TB4, FFHT1514TS0, FFHT1514TS1, FFHT1514TS2, FFHT1514TS3, FFHT1514TS4, FFHT1514TW0, FFHT1514TW1, FFHT1514TW2, FFHT1514TW3, FFHT1514TW4, FFHT1521QW4, FFHT1614QB1, FFHT1614QB2, FFHT1614QB3, FFHT1614QB4, FFHT1614QB6, FFHT1614QQ1, FFHT1614QQ2, FFHT1614QQ3, FFHT1614QQ4, FFHT1614QQ5, FFHT1614QQ6, FFHT1614QW1, FFHT1614QW2, FFHT1614QW4, FFHT1614QW5, FFHT1614QW7, FFHT1614QZ1, FFHT1614QZ2, FFHT1614QZ3, FFHT1614TB0, FFHT1614TQ0, FFHT1614TW0, FFHT1621QB2, FFHT1621QB3, FFHT1621QB4, FFHT1621QB5, FFHT1621QB6, FFHT1621QS2, FFHT1621QS3, FFHT1621QS4, FFHT1621QS5, FFHT1621QS6, FFHT1621QW2, FFHT1621QW3, FFHT1621QW4, FFHT1621QW5, FFHT1621QW6, FFHT1621TB0, FFHT1621TB1, FFHT1621TB2, FFHT1621TS0, FFHT1621TS1, FFHT1621TS2, FFHT1621TW0, FFHT1621TW1, FFHT1621TW2, FFHT1800PS0, FFHT1814QB2, FFHT1814QB3, FFHT1814QB4, FFHT1814QW2, FFHT1814QW3, FFHT1814QW4, FFHT1814TB0, FFHT1814TB1, FFHT1814TW0, FFHT1814TW1, FFHT1821QB4, FFHT1821QS4, FFHT1821QW4, FFHT1821TB0, FFHT1821TB1, FFHT1821TS0, FFHT1821TS1, FFHT1821TW0, FFHT1821TW1, FFHT1831QE4, FFHT1831QE5, FFHT1831QE6, FFHT1831QM4, FFHT1831QM5, FFHT1831QM6, FFHT1831QP4, FFHT1831QP5, FFHT1831QP6, FFHT1831QQ4, FFHT1831QQ5, FFHT1831QQ6, FFHT1831QS4, FFHT1831QS5, FFHT1831QS6, FFTR1514QB3, FFTR1514QB4, FFTR1514QB5, FFTR1514QW2, FFTR1521QW3, FFTR1614QW5, FFTR1614QW6, FFTR1614QW7, FFTR1614RW0, FFTR1614RW1, FFTR1621QB3, FFTR1621QB4, FFTR1621QW3, FFTR1621QW4, FFTR1814QB2, FFTR1814QB3, FFTR1814QS2, FFTR1814QS3, FFTR1814QW2, FFTR1814QW3, FFTR1821QB3, FFTR1821QM3, FFTR1821QS3, FFTR1821QW3, FFTR18D2QB3, FFTR18D2QS3, FFTR18D2QW3, FGHI1865SE4, FGHI1865SF4, FGHI1865SP4, FGHT1835SF1, FGHT1846QE2, FGHT1846QE3, FGHT1846QE4, FGHT1846QF2, FGHT1846QF3, FGHT1846QF4, FGHT1846QP2, FGHT1846QP3, FGHT1846QP4, FGTR1845QE3, FGTR1845QF3, FGTR1845QP3, FPHT1897TF0, FPHT1897TF1, FPHT18D3RS3, FPTR18D3RS3, FTMD18P4RW2, FTMD18P4RW3, LFHT1831QE4, LFHT1831QE5, LFHT1831QE6, LFHT1831QF4, LFHT1831QF5, LFHT1831QF6, LFHT1831QP4, LFHT1831QP5, LFHT1831QP6, LGHT1846QE4, LGHT1846QF4, LGHT1846QP4, NFTR18X4QB3, NFTR18X4QS3, NFTR18X4QW3, WWTR1811QW2, WWTR1821QW2, WWTR1821QW3, plus additional Frigidaire and Electrolux models. Contact us to verify your model number before ordering.

💡 Pro Tip

✓ Model-Specific Repair Pages