The short answer
Most new freezer noises come from something touching something else, or from a cabinet that has been moved. On this cabinet the first suspect is tubing or a wiring loom resting against the cabinet.
What you observe
- A buzz from the back or the base that comes and goes — The compressor or its mounts, and the timing tells you which.
- A rattle that stops when you press on the cabinet — Panel or tubing resonance rather than a failing part.
- A knock once or twice an hour — Expansion, or a defrost cycle starting on a frost-free cabinet.
- NEAR MISS — noisy and also not holding temperature — Then the noise is a symptom; the cooling-failure page ranks the real fault.
Causes, most likely first on a Smad freezer
- Tubing or a wiring loom resting against the cabinet — This is almost always the cause when the noise appeared straight after the cabinet was moved. Ranked first on a Smad freezer: it is the classic after-a-move noise, and it costs nothing to correct.
- Cabinet not level, or touching a wall — A freezer resting against a wall transmits ordinary compressor vibration straight into the structure.
- Drain pan or base tray vibrating — It is always mistaken for the compressor because it sits directly above it.
- Compressor mounts and ordinary running noise — Worn rubber mounts let the vibration into the cabinet instead of absorbing it.
Check in this order, and why
- Look at the rear of the cabinet for lines touching the frame or each other — With the power off, move a suspect line a few millimetres and listen again.
- Push gently on the top corners and check the clearance behind — Contact with a wall is enough on its own to cause this.
- Reach under with the power off and check the pan or tray is seated — A tray that moves under light pressure is the source.
What an owner can safely check
- With the power off, check the rear tubing for contact points and ease any touching line clear by hand — A few millimetres is enough. Move lines gently and never bend one sharply.
Tools: torchAbout 20 min
- Level the cabinet on its feet and pull it far enough forward that nothing touches the wall — A cabinet standing square with clear air behind it loses most of its noise immediately.
Tools: spirit level, adjustable spannerAbout 20 min
- STOP HERE if the next check needs a panel off or a meter on live terminals — That is where the owner checks end and a service call begins, whatever the ranking says.
Before you open anything
Safety
Disconnect power before opening anything and let any capacitor bleed down before you reach past a board. Frost comes off with warm air and time, never with a blade. Sealed-system and refrigerant work is licensed work and is never an owner job. Empty a loaded freezer before you move it.
When to call a technician
Levelling, reseating a tray, clearing frost and easing a contact point are all owner work. A fan behind the rear panel, a compressor mount or a failing bearing is not. If your unit is an absorption model running on gas, the gas side is not owner work: a licensed gas technician handles the burner, the flue and any smell of gas.
Nearest pages of this class
What this page does not cover
This page covers the Smad freezer as a class, not one family or model line. Where a family- or model-specific page exists for your unit it is linked above and it is the better answer — read it first. Deliberately not here: part numbers, wiring colours, panel removal order and torque figures, all of which differ between families under one nameplate.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
