The short answer
Most refrigerator noise comes from one of three fans and pans rather than from the compressor, and the timing of the noise tells you which. A noise that starts when the door closes is different from one that runs all the time. Open the freezer door and hold the light switch in. If the noise changes or stops, it is the evaporator fan behind the rear panel; if it continues unchanged, it is at the back of the cabinet. On a Smeg SpA refrigerator the cause that ranks first is evaporator fan blade catching frost.
What you observe
- A tick or scrape that changes when the freezer door is opened — The evaporator fan behind the rear panel.
- A loud flutter from the bottom or back of the cabinet — The condenser fan with something caught in it.
- NEAR MISS — a gurgle or a hiss after the cabinet stops — That is refrigerant settling, and it is entirely normal.
Causes, most likely first on a Smeg SpA refrigerator
- Evaporator fan blade catching frost — Frost builds on the shroud behind the freezer panel and the blade ticks or scrapes against it, loudest just after the door has been open. It ranks first on a Smeg SpA refrigerator because a built-in installation breathes through a narrow cabinet cut-out, so anything airflow-related surfaces here long before it would on a free-standing machine.
- Condenser fan hitting debris in the plinth — The fan beside the compressor draws in dust, paper and pet hair, and a scrap caught in the blade gives a loud intermittent flutter. Second on this platform: anything that falls under a cabinet ends up at that fan, and a shallow plinth collects more of it.
- Drain pan or a cover panel rattling — The evaporation pan sits loose under the cabinet by design, and a pan that has shifted buzzes against the compressor mount. Ranked here because it is a rattle rather than a hum, and it is usually cured by hand in a minute.
- Cabinet not level, drumming on the floor — A cabinet standing on three feet transmits every compressor vibration into the floor, and the floor is louder than the appliance. Last, and the reason to work down the list rather than guess: the stance is free to correct and it is behind more noise complaints than any component.
Check in this order, and why
- Open the freezer and hold the door switch in, listening for the noise to change — A noise that stops with the door open is the evaporator fan.
- Unplug the cabinet and look into the plinth or the back with a torch — Debris in the blade path is visible and free to remove.
- Press gently on the lower rear panel while the noise is happening — A noise that changes under hand pressure is a loose panel or pan.
What an owner can safely check
- Unplug the cabinet, clear the plinth or rear grille by hand and vacuum the area — Never reach into a blade path with the cabinet plugged in.
Tools: vacuum, torch, gloveAbout 20 min
- Unplug the cabinet and re-seat the drain pan squarely in its brackets — Empty and rinse it while it is out.
Tools: torch, clothAbout 15 min
- STOP HERE if the next step needs a meter on live terminals or a panel off — That is where an owner check ends and a service call begins, whatever the ranking above says.
Before you open anything
Safety
Unplug the cabinet or switch off its breaker before reaching into the plinth, behind the cabinet or near any fan blade — a capacitor can hold a charge after the power is off.
When to call a technician
Call when the noise is a repeated relay click with no compressor run, or a grinding that continues with the cabinet unplugged at every fan you can reach. On a European-controlled machine, ask what the control was reporting when it stopped — it usually records why it aborted, and that shortens the visit.
Nearest pages of this class
What this page does not cover
This page is written for the Smeg SpA refrigerator as a class, not for one family or model line. Where a family- or model-specific page exists for your unit it is linked above, it is the more specific answer, and it is the one to read first. Deliberately not here: part numbers, wiring colours, panel removal order and torque figures, all of which differ between families under the same nameplate.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
