Hi Mike, thanks for including the serial number. That lets us answer the age question first and then get to the cooling problem.
How old is your C450?
Fisher & Paykel hides the build date in the first two letters of the serial number. The first letter is the last digit of the year (from the word C-U-M-B-E-R-L-A-N-D, so C=1, U=2 … B=4 … D=0). The second letter is the month (from F-I-S-H-E-R-P-A-Y-K-U-L, so F=January).
Your serial BFQ700938 reads as January of a year ending in 4. The C450 is an older top-mount model that is no longer sold, so 2014 and 2024 are very unlikely. Most likely the fridge was built in January 2004, and possibly in 1994. Either way it is at least 20 years old. That matters for whether a repair is worth the money, which is covered at the end.
“The motor runs but it isn’t cooling”: what that usually means
The “motor” you hear is the compressor. A running compressor with a warm cabinet points to one of the problems below. They are listed roughly from easiest and cheapest to most serious.
- Dirty or blocked condenser. On a C450 the condenser is the grille or coil at the back or underneath. If it is caked in dust, or the fridge is pushed hard against the wall or into a tight cabinet, the heat can’t escape and cooling drops off. This is common in an Australian summer. Vacuum the coil, leave at least 50 mm of air gap at the back and top, and give it 24 hours.
- Frost blocking the airflow (fridge section only). If the freezer is still cold but the fridge is warm, cold air isn’t reaching the fridge. Check the back wall of the freezer for a thick sheet of frost or ice over the vents. On these models that usually means the automatic defrost isn’t working: the defrost heater, the defrost thermostat or the timer/control. As a test, unplug the fridge with both doors open for 24 to 48 hours. If it cools properly afterwards and then slowly fails again over 1 to 3 weeks, the defrost system is confirmed.
- Evaporator fan not turning. Open the freezer and press the door switch. You should hear or feel a fan. If the compressor runs but there is no fan, the freezer may stay partly cold while the fridge warms up. A fan motor is a moderate repair.
- Door seal leaking. Close the door on a sheet of paper all the way around. If it slides out easily anywhere, warm, humid air is getting in. You’ll usually see frost or condensation near the gap.
- Refrigerant leak or a worn-out compressor (sealed system). If both the freezer and the fridge are warm, the compressor runs nonstop, and the coils inside the freezer are not frosty at all, the gas has most likely leaked out or the compressor is no longer pumping. On a fridge this age that is the most common end-of-life failure.
Is it worth repairing?
A condenser clean, a door seal, a fan or a defrost part is a sensible repair even on an older fridge. A sealed-system repair (leak search, re-gas, possibly a compressor) usually costs more than a 20-year-old top-mount is worth. At that point we’d honestly recommend replacing it. A new fridge will also use noticeably less power.
In Australia any work on the refrigerant has to be done by an ARCtick-licensed technician. Ask for that when you call someone local in Perth. We’re based in Houston, so we can’t come out, but we’re happy to help you read the symptoms.