My bathroom exhaust fan makes a clicking noise, even when it is not turned on - of course it is not constant but it is regular and strange. It is a fan/light combo for the bathroom ceiling. Light and fan both work.

I recommend using MR (Moisture Resistant) drywall for the bathroom, and possibly for the basement if there are moisture issues. It is not much more expensive, and it can save you a big headache later

The roaring noise is probably the fan blades (looks like a hamster wheel) are worn out as it rotates on the spindle/shaft.

It may be a problem with the 4" exhaust ducting, that connects to the exit part of the fan, has come loose. Theres a damper (kinda like a flapper) at the fan/ducting joint may have broken off and may be sitting sideways in the ducting flapping around inside the duct.

At any rate I highly doubt its wiring. Sounds like its time to pull the fan cover off (turn the power off first via the wall switch or the service panel breaker would be even better) and look at the fan blades. Clean off any dust bunnies, lint, etc. and turn the fan back on. Did the noise stop?

If nothing looks out of place and it still makes noise you'll have to get in the attic and remove the ducting from the fan and see if theres a problem at the connection there. Maybe a squirrel put its bedding in the ducting? It happens.

Could be lots of reasons for the noise but wiring it wrong wouldn't cause roaring. The fan wouldn't work, or worst burn up, if wiring was the issue. The problem is the more than likely the fan blade assy is worn out or something is restricting the air flow in the ducting going to the outside of the house.

remove the cover and clean anything in the vent , check the fan for anything that could be touching it, as the back draft comes through the vent, something could just be touching the fan blade as this draft makes the blade turn slowly, which would create a ticking noise

Range hood motors, bathroom exhaust fan motors all share the same thing. They become coated with grime inside the shaft of the rmotor due to their exhaust feature of sucking dust and grime over the motor, which is open. The only solution is to get access to the motor and clean the fan blades and squirt a little WD-40 down the shaft as that is where the noise comes from. The dirt and grime build up on the motor shaft, and eventually starts rubbing the bushing where the shaft rest and makes a noise. Yo must remove this from the shaft and allow a little play, and lubrication which the WD-40 will supply.

Okay jmurphy177...

You are now on record...
Any injuries or property damages after this are
COMPLETELY YOUR RESPONSIBILITY.

There is a SERIOUS reason the instructions say
to have a qualified electrician do the install...

Precisely...
There is NO WAY this switch may be turned around
and
IT MUST have a NEUTRAL wire to OPERATE CORRECTLY.

Quite often a switch box will only have the
hot wires extended from the light fixture...

The COLOR of the wires in that configuration
MEAN NOTHING... and you are creating an EXTREME
HAZARD.

Please heed this warning... Everything else = negligence.

Most likely an ELECTRICIAN can run the additional wire you
need to function...

BATHROOMS are "WET" location and require SPECIAL SKILLS not to be deadly.

Carnac the Magnificent

It could be that the fan button is sticking or a contact has welded itself closed therefore its getting power all the time.

no its not exactly a HD failure u need to remove the keyboard and look if something is stucking in ur fan...there might be the possibility of dust in it and even a minute thing can damage a lot..
cheerrss...pls rate..

First turn the power to the fan OFF. Take it down from the ceiling by removing the screws holding the cover on. Then remove the screws holding it to the ceiling. Then unscrew the screw caps that twist (connect) the wires from fan motor to the house wiring. Do a general clean up on the fan. Use an old paint brush to get in the hard to get at places. Rotate the fan by hand. If it does not rotate freely, put some oil on the shaft where it goes into the motor, and put some on where the shaft comes out the back. If it still does not rotate freely, buy a replacement and install it.

I'm guessing that water isn't splashing up on this fan's motor, so the moisture that is causing the rust must be water vapor. The exact same water vapor that the fan is supposed to be removing. I have two suggestions before replacing the entire fan. One is to make sure that the ducting that carries the moist air out of the bathroom (and preferably out of the house altogether) is free of obstructions and that the fan can actually do it's job. Second is to actually run the fan, and run it a lot longer than you probably are right now. If it is running while you are in the shower and then you turn it off after you leave the bathroom, it can't possibly be removing that moisture. I'd invest in a countdown type timer and replace the existing switch with that. Set that thing for 30 or 60 minutes when you get in the shower and let it turn it off automatically.

There is no solution. I have the same problem. The issue is that the system clicks as the thermostat regularly checks the temperature. It is a major design problem and I hate it too/