How to clean and repair the fan in your calorifer

Introduction

If the fan in your calorifer squeals, sticks, or smells of dust, a thorough cleaning and bushing service will restore silent and safe airflow. This guide shows you how to open the housing, remove years of dust, repair worn motor bushings, lubricate the assembly, and rebuild the heater while respecting safety rules and possible warranty limits.

What you need

Step 1 Disconnect power and review safety

Pull the power plug from the wall before touching any part of the calorifer.
Work only on a cooled-down unit in a dry, well-ventilated area with good lighting.

Step 2 Remove the outer housing

Lay the heater on its back and undo all visible flathead screws that hold the shell together.
Newer units usually hide the fan behind two screws and spring clips, yet the disassembly sequence remains identical.
Put the screws aside in a dedicated tray so none are lost during the repair.

Step 3 Separate the shell and expose components

Lift the front and rear covers away, watching for tight design trims and hidden tabs.
Avoid tugging on internal wires while removing the casing.

Step 4 Clear dust from the interior

Vacuum or blow away all packed dust from heaters, fan blades, and grilles using a brush, toothbrush, or compressed air.
Dust on hot elements is a potential fire source, so remove every deposit.

Step 5 Document wiring before disconnection

Photograph the exact order and colours of all motor leads so reassembly is foolproof.
Label any identical connectors if photos are unclear.

Step 6 Extract the fan motor

Unhook the wires, undo the fastening screws, and lift the motor-fan assembly from the frame.
Rotate the fan by hand; rough grinding indicates bearing damage.

Step 7 Inspect bushings for failure

Check each bronze bushing: if it has fallen out, crumbled, or allows excessive shaft play, it must be replaced or reset.
Confirm the rotor shaft is not blue or darkened, which would signal overheating.

Step 8 Understand and position the new bushing

A bushing set contains the sleeve, felt oil wick, and tolerance ring that locks it in place.
Install the sleeve with its sharp edge facing outward so the ring cannot jump during operation.

Step 9 Stake the bushing securely

Pad a small vise with wood, align the new bushing in its housing, and apply even pressure to seat it.
If the vise alone cannot flare the metal, use a socket as a drift, then tap the edge with a punch and hammer to peen the housing lip over the sleeve.
Work around the perimeter gradually to avoid cracking the casting.
Repeat the staking on the opposite side of the motor.

Step 10 Soak and lubricate the bushings

Add a few drops of machine oil onto the felt until it is fully saturated.
Slide the rotor shaft through each sleeve and spin it gently so oil wicks into the contact surfaces.

Step 11 Rebuild the motor housing

Position the endbells, plastic spacers, and rotor exactly as photographed, ensuring the long shaft faces the fan wheel.
Insert the spring washer and retaining screw, then tighten opposite sides alternately so the rotor runs true.
Verify the shaft turns freely without scraping before proceeding.

Step 12 Degrease the coupling area

Clean any oil from the motor shaft section that will mate with the rubber fan coupling using solvent or degreaser.
Prevent solvent from seeping into the motor windings.

Step 13 Lubricate rubber parts for easier assembly

Apply a light coat of oil to the fan coupling and mounting grommets so they slide into place without tearing.
Keep the rear rubber surface oil-free, as it must grip the shaft firmly.

Step 14 Mount the motor back into the frame

Fit any distance washers first, lower the motor into position, and align the shaft with the rubber seat.
Start all motor screws by hand, then alternate tightening to draw the assembly down evenly.

Step 15 Close the housing and perform a test run

Reinstall the heater covers, insert every screw, and check that the grille does not touch the fan blades.
Reconnect the plug, switch the calorifer on, and confirm smooth rotation and normal heating.
If abnormal sounds persist, shut off power immediately and recheck bushing seating.

Conclusion

Your calorifer’s fan now spins freely, runs quietly, and no longer risks dust-induced overheating. Keep the grille clean and repeat interior cleaning each season to extend the motor’s life and avoid future bushing wear.