A bathroom exhaust fan that has stopped working — or that runs but never clears the steam — is more than an inconvenience in Melbourne. Through the damp winter, a non-functioning fan quickly leads to condensation, peeling paint and mould. This guide walks through the common fault patterns in order, explains what each symptom usually means, and shows what you can safely check yourself before calling a licensed technician.
Fan Won’t Turn On
If the fan is completely silent and does nothing when switched on, the fault is most likely electrical or a dead motor.
Is it the switch or the fan?
If the fan is wired to the light switch and the light still works, power is reaching the switch — the fault is in the fan’s own wiring, the fan motor, or a separate fan switch or timer. If the fan has its own switch, check whether that switch operates anything else. A completely dead fan with a working light points to the fan unit or its dedicated wiring.
Humming versus silent
Listen closely. A faint hum with no blade movement means the motor has power but cannot turn — a failed motor or capacitor, or a seized impeller. Complete silence means no power is reaching the motor — a switch, wiring or circuit fault. This distinction tells the electrician where to start. Either way, replacing a failed fan is a complete job from $250.
Runs But Extracts Poorly
A fan that runs normally but leaves the bathroom full of steam is moving far less air than it should. This is one of the most common complaints in Melbourne homes and usually has a fixable cause.
- Not ducted outside: if the fan vents into the roof cavity rather than through a roof cowl or eave, the moisture has nowhere to go and the room stays humid. The fix is to add a proper duct and discharge.
- Restricted duct: a long, kinked, crushed or sagging duct chokes the airflow. Sagging flexible duct also collects condensed water, making it worse. Re-running the duct cleanly restores airflow.
- Clogged fan: dust and lint on the impeller and grille can halve a fan’s real airflow. Cleaning often restores performance — see our cleaning guide.
- Undersized fan: a fan below the 25 L/s minimum, or one whose ducted airflow falls short, simply cannot keep up. Upgrading to a correctly sized unit is the answer.
- No make-up air: if the door seals too tightly, replacement air cannot enter and the fan cannot extract. A small door undercut or vent fixes it.
Spins Slowly or Struggles to Start
A fan that spins slowly, takes a few seconds to get going, or sounds laboured is showing early signs of motor wear or a heavy dust load. The starting capacitor that gives the motor its initial torque can weaken with age, leaving the motor sluggish to start. A thick coating of dust on the impeller adds load and slows it further, while also unbalancing the blades and causing noise.
Start by cleaning the fan thoroughly — this resolves a surprising number of “slow fan” cases. If the fan is clean but still slow to start, laboured, or noisy, the motor is wearing out and the fan is best replaced before it fails completely. A slow, struggling motor also draws more current and runs hot, so it should not be left indefinitely.
Stops and Starts or Cuts Out
A fan that runs then cuts out, or cycles on and off, points to one of a few causes. A failing motor can overheat and shut down on its thermal protection, then restart once it cools — a clear sign the motor is near the end of its life. A loose wiring connection or a faulty switch or timer can interrupt the supply intermittently. In fans controlled by a humidity sensor, the sensor may be switching the fan as humidity crosses its threshold — which is normal behaviour, not a fault.
If the cut-outs coincide with the fan getting hot, treat it as a failing motor and replace the fan. If they seem random and the fan stays cool, the cause is more likely in the switch, timer or wiring, which a licensed electrician can test and repair.
Safe Checks You Can Do Yourself
- Turn the fan off at the switch before touching anything.
- Remove the cover — most pull down against spring clips or unclip by hand — and inspect the impeller and grille for dust and lint buildup.
- Clean the cover and visible impeller with a vacuum and a damp cloth (cover only). Do not wet the motor.
- Note the symptom: does the fan hum, spin slowly, or stay silent? This helps the technician.
- Check the light: if the fan shares the light circuit, confirm whether the light still works.
- Refit the cover and test. If cleaning has not restored normal operation, book a licensed technician.
When to Call a Professional
Call a licensed technician when cleaning has not restored the fan, when the fan hums but will not spin, when it is slow, laboured or cutting out, or when it is completely dead. In most cases where the motor has failed, replacing the fan is the sensible fix — exhaust fan motors are integral to the unit and rarely economical to replace alone — and a replacement is a good chance to upgrade to a quieter, properly ducted fan that actually keeps the room dry. A like-for-like replacement starts from $250 as a complete job. Call FreshDuct on 0431 918 137.