How to clean your heating ducts

How to clean your heating ducts

When was the last time you cleaned your ducts? You can reduce allergies and breathe cleaner air by eliminating the dust and dirt that accumulates in your heating. The good news is that your heater will last for longer because there is less dirt wearing out its components. 

This method will remove roughly 85% of the dust in your system without spending any more than the cost of your new furnace filter. 

It doesn’t matter which ducted system you own, the method for all is much the same. 

You will need:

  1. New Furnace Filter.  Make sure you choose the right filter and install it at the end of the clean. 
  2. Vacuum. A household-type vacuum with a decent hose attached will work, but a heavier-duty vacuum is ideal.
  3. Brush. Something closely resembling a toilet brush will work best, but a stiff-bristle paintbrush or something similar will do.
  4. Screwdriver or Hex Driver. Your registers are likely held in place by fasteners. You will need to use whatever tool fits the fasteners, usually a Phillips screwdriver or 1/4″ hex driver.
  5. Paper Towels. Unless you want to do a lot of dusting and sweeping right after you clean your ducts, you will find these useful to cover some registers while you clean others.  

Step-By-Step Duct Cleaning 

  1.  Cover supply registers with paper towels. (These are the openings that supply heated air to the rooms.) You do this to keep dislodged dust from drifting into the rooms as you work. Simply lift the register, wrap the paper towel over the top of it, and replace it. 
  2.  Turn on fan while you are cleaning. This will move the dust along that you are going to loosen with your banging and brushing. Set the thermostat to “fan on,” and shut off the “heat/cool” mode so that only the fan is running. If you don’t have a fan-only option, you can run the heat. 
  3. Check that the old furnace filter is in place so that the dust you knock loose doesn’t end up getting pulled into the fan motor.
  4. Knock loose dust in ducts. Tap handle of your brush on any accessible duct. This will help break up any deposits of dampened dust that may have stuck to the insides of the duct.  
  5. Vacuum/sweep the dust in your supply registers. Use the hose to catch any dust that is being pushed out by the fan, and sweep as far into the register’s piping as your hose can reach. Use your brush to scuff loose any built-up dust in the register. As you go through the office/home sweeping out the supply registers, you can remove and dispose of the paper towels. 
  6. Clean return air registers. Sweep out your return air registers. These will probably be fastened with a screw and require your tool to remove them. Again, vacuum and sweep as far back into the register piping or cavity as you can. 
  7. Turn off fan and furnace and the power off to the furnace via the service switch or breaker panel. Do not just shut off the thermostat, because that doesn’t turn off the power to the unit. 
  8. Clean out blower compartment and return air boot. With the power off, you can remove the panels on the front of the furnace and access the blower compartment and the return air boot. Use your vacuum to sweep up the dust built up in the blower compartment and return air boot. This is where the great bulk of your dust will be. Since you’re in here, you should clean the furnace fan as well. 
  9. Replace furnace filter. Buying a better filter will cut down the dust. But the better the filter, the more often you should change it; a dirty filter restricts the airflow to the fan, which results in the blower motor running hotter and reducing its lifespan.