everything that a plumber can do for you

everything that a plumber can do for you

How To Replace An HVAC Baseboard Diffuser

by Christopher Taylor

If you have HVAC duct openings along the wall  or floor edges, they likely use a diffuser. The diffuser ductwork only runs to the edge of the floor or ceiling, but it doesn't connect to the wall or ceiling. A diffuser can get damaged occasionally, which can prevent air from circulating properly. It is simple to replace an HVAC diffuser by following these tips.

Prepare to Work

For this project, you need:

  • work gloves
  • tape measure
  • putty knife
  • Phillips or flat-blade
  • screwdriver
  • hammer
  • chisel
  • silicone caulk and caulk gun
  • replacement diffuser

Shut off the power to the system from the breaker box, and let the unit cool. Turn the thermostat to the lowest setting. If you don't know what breaker controls the unit, turn off the main house power supply.

Remove the Old Diffuser

Don't remove the diffuser with bare hands, since there could be sharp edges. If the diffusers are attached to the ceiling, set a step-ladder , so you can easily access them. 

The diffuser commonly has several sets of screws. Remove the screws by turning them to the left with a screwdriver, and set them aside. Some ceiling diffusers may have posts in the center that come off by rotating them to the left by hand. 

To remove caulk, chip it off with a putty knife, then use a hammer and chisel to tap the edge. Grip the diffuser, and take it out of the wall. If you still can't remove the  diffuser, chip some paint off the wall.

Install the New Diffuser

Clean the opening with a vacuum cleaner and hose attachment, but don't force the hose inside. Use the tape measure to determine if the new diffuser will fit over the hole. Diffusers tend to be slightly larger than the space but you don't want them to small.

You also don't have to buy the same shape of diffuser, since they all attach in the same manner. Set the new diffuser in place until it is flush with the wall or ceiling, and fasten it with screws.

 Some diffusers on ceilings may attach to the flexible air duct. Pull the duct over the circular opening of the diffuser. Add a strip of duct tape to secure it, then attach the screws. 

If the ceiling diffuser has  a post, reattach it by turning it to the right. Add a bead of caulk around the opening, and let it dry.

Restore power to the unit, and test the instillation. If you don't trust your skill, or the unit fails to work, contact an air conditioning maintenance service.


About Me

everything that a plumber can do for you

Many people think that a plumber is there to be called to unclog toilets and drain pipes, but they don't understand that there are a number of other tasks that a plumber can do around the home. As the wife of a plumber, I know very well how much my husband does when he is out working. He comes home and tells me his fun stories about the superhero that was flushed down the toilet or the hot water heater that nearly exploded. My blog is filled with all sorts of tips, stories and information that can help you get a better idea of everything that a plumber can do for you.