Repairing Bathroom Fans

This sounds like a proper riveting read doesn’t it ? – As you probably know, I think its better to repair than replace for multiple reasons, but my two main reasons are Design and Sustainability. The fans in the units are pretty nice, lower noise and decent performance combined with good looks so why mess with that combo?

Why?

The apartments have been around for over 10 years now and some of the original fixtures are showing age and wear. The fans are still functional, but they are now noisy. What started out as a quiet 1.5 Sone’s bathroom fan is now probably close to 3 or 4. Thats that resonating annoying fan nosie.

Why is this? – well, long story short, the motor blowers are not engineered amazingly well, and most of the noise is from the vibration of worn bearings and bushings. (blower is the item which sucks the air) The blowers in these units are Broan 744’s which have a horizontal blower. This by default is not bad, but the extra precautions the manufacturer should have taken when designing this configuration haven’t been taken. . Basically there is somewhat excessive load on the shaft bearings from the blower cage. That load combined with prolonged use – (12years of use), and they wear and create vibration causing noise and resonating in the cavity above the ceiling.

Can you fix the bearings? – in short no, they are part of a larger assembly, motor shaft, cage. Theoretically you could fix, if you had a lot of specialist tools to deconstruct the assembly and remove bearings, and at that point it might not be financially worth it. If I had the tools, I would certainly give it a go!

What?

What’s the fix? – to make it quiet like new is replacing the motor, shaft and blower cage.
Fortunately this is all available for replacement for about $70. Parts are somewhat hard to find as often Broan is out of stock, but other online dealers will have them. If you cannot find the blower motor you can always buy a complete new unit and strip the motor out . A full new units costs about $150

Part Number: 1101122
Part Description: Blower Assembly – Includes Motor, Blower Wheel, & Mounting Bracket

Here is old and new motors / blower. You can see the company have changed the design from a silver metal blower cage to black plastic, probably for cost but also the plastic is lighter and will make the bearings last longer. Also the improved motor has an electrical noise suppressor on the outside.

How?

Its a sort of fiddly job, but it’s not technically difficult, nor does it need special tools. It helps to have small hands and be pretty dextrous. Also a lot of work is done overhead or at face height from an ergonomic perspective.
The basics are removing the internals, removing the motor, plopping in a new motor and installing the rest of the internals back in. Make sure you have a step stool or something to stand on, it makes working overhead a lot easier.

  1. Turn off the electricity! doh.
  2. Remove the lightbulb.
    Remove the plastic beige shroud via two little springs that are be unhooked from the inside,
  1. Remove the motor and blower.
    The unit has three 3/8″ nuts holding it in place, you can remove TWO lower nuts first then you have to do the next step before removing the one last upper nut. The motor has flange which is bolted to the internal ducting via three metal studs. (you can see the studs in step #6)
    The nuts go on studs so they are easy to locate. The space is small and you will need a 3/8 driver with extension. You can use a driver on a screwdriver handle or a ratchet type. You will have to contort your hands a bit to get to the nuts and get the tool in place. This is the tricky stuff. I found it easiest to break the initial torque with a driver and then remove the nuts with my fingers.
    Unplug the motor’s black wire from the light fixture.
  1. Remove the light fixture. There are two 3/8″ nuts (left and right) that need removing from studs and the light fixture will simply slide off and dangle on the red,blue white wires.
  1. Remover the final upper motor nut. (The light fixture was blocking this nut before)
  2. Pull out the old motor and blower, you will have to reposition / wiggle the light fixture around a bit so you can get the motor out of the hole in the ceiling. When done, If you look inside, you will see the three studs.
  1. Put the new motor and blower in. You will have to do some wiggling, manipulating the light fixture above the new motor unit. Note there is a flat edge to the flange, this shows the orientation of the motor. It will only fit one way, as the flat edge goes closest to the metal internal wall, thats why its flat and chopped off in design.
    The motor flange has three holes which will line up and sit on the three studs. (see above photo)
  2. With the motor in place (it should stay there without the nuts), re install the light fixture to the two light fixture studs. it need only be loose fit, as you are going to have to remove it again in a minute to make room.
  1. Install two lower motor nuts. Tighten them down snug, but don’t force the crap out of them and strip the things.
  2. Remove the light fixture (again) to access and install the upper motor nut.
  3. Re install, the light fixture. Snug the nuts down but, you know, don’t strip em
  4. Plug the motor to the light fixture.
  5. Reinstall the shroud, place the shroud up to the ceiling opening and reach through to clip the springy things. you will see the holes in the light fixture for the open hooks of the springy things. They are a little fiddly, but doable. Pop the bulb in and you’re done.

Summary

Time ~45mins
Cost : ~$70-90
Special Tools – no
Difficulty – you decide.

Bonus Tip

If you want a bonus tip, heres one. When the motor / blower is out, you can reach your am back in the vent and check the condition of the damper. You should feel that its clean ish, and easy to move / open and closed. You wont be able to see it, but you can feel.

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