The short answer for this line
On PFQZ units the useful question is not how loud the noise is but what it follows. Separate continuous noises from rhythmic ones, because they come from different places, which is why the order below differs from the brand-generic one. The order below puts a worn fan bearing first and compressor mounts that have perished last, and that order is the point of the page.
What this looks like on these models
- A hard knock at the start of each run — One thump as the compressor picks up, then a steady hum; often another at the stop.
- A rattle that comes and goes within a run — It appears for a few seconds at a particular point and then clears on its own.
- A continuous whine while air is moving — It tracks the fan rather than the compressor and stops when the fan does.
- A buzz that you can feel through the case — Felt as much as heard, and it changes if you rest a hand on a panel.
- NEAR MISS - no noise at all and nothing is cold — A silent unit is a supply or a start fault, not a noise fault, and it belongs on the cooling page rather than here.
Causes in likelihood order on this platform
- A worn fan bearing — Ranked first on this line: it develops rather than appearing, gets worse in the cold, and is often quieter for a while after a run, which is how it is distinguished from a foul.
- The fan blade catching on something — It ranks high because it is easy to confirm and because ice against a blade means a second fault worth knowing about.
- Loose fasteners, a cover or a grille — Then: the noise is usually intermittent, because the panel only buzzes at one point in the cycle when the frequency matches, and that intermittency is the clue.
- Compressor mounts that have perished — Last, and the reason the order matters: the compressor sits on rubber mounts, and when those harden the unit transmits everything it does into the case. The noise is a hard knock at start and stop rather than a hum.
Check in this order, and why
- Judge whether the noise is continuous or rhythmic — Note whether the noise is present at every start or only after a long run; a bearing that quietens as it warms is a bearing on its way out.
- Match the rhythm of the noise to the fan — Listen for whether the noise follows the fan or the compressor. A sound that starts and stops with airflow, and changes pitch as the fan speeds up, is a fouled blade.
- Rest a hand on each panel while it runs — Check the fasteners around the machinery bay cover for one that has backed out.
- Only after the free checks, consider the mounts — With stance, contents, panels and surface all excluded, a knock that remains at every start points into the machinery bay. That is the point to stop.
Safety first
Safety
Isolate the unit at the plug or the breaker before any cover comes off - a capacitor can hold a charge after the power is off. Do not hold a panel against the case with a hand while the compressor runs; use packing and let go of it.
The line between a fix and a call
Call when the noise is continuous rather than rhythmic and does not change with load, position or clearance: that combination points at a bearing or a mount, and both are behind a panel.
The rest of this line
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
