Heating, Cooling and HVAC

Because heat plus moisture equals mold and mildew, every bathroom needs a way to combat this combination. The most efficient way is to exhaust bathroom air outside.
…………………………….

Most new homes come with a fan already installed; older homes–if they have a fan at all–usually have one that is underpowered.

Whether your home is new or old, check the rating of your fan. If it is under 80 cfm (cubic feet per minute), replace it with a stronger one.

Replacing an existing fan with a new one is about as simple as replacing a vanity light. Just make sure the new unit will fit in the existing opening and that it uses the same type and size of ducting.

Installing a new fan requires cutting a hole in the ceiling where the overhead light fixture is and routing vent pipe to an exterior wall, where you’ll cut through and connect a vent cap.

In this situation, you will want to purchase a fan that has a built-in light. If the ventwork is beyond your skill level, call in a contractor

1.Turn off the power to the existing fixture at the service panel. Remove the old fixture. Position the template or housing on the ceiling so it aligns with the ceiling joist. Trace around the template or housing to locate the opening. Alternatively, if you have access from above, position the housing or template next to the joist and trace around it.

2.Cut out the opening according to the manufacturer’s directions using a drywall saw, saber saw, reciprocating saw, or utility knife.

3.Attach the ductwork and insert the housing up into the opening. Secure the housing to the joist with the fasteners provided. Make sure to fill all the mounting holes with fasteners to reduce vibration and ensure noise-free operation.

4.Connect the fan unit to the existing wiring following the manufacturer’s wiring diagram. Be sure the electrical circuit is turned off when doing all work.

5.Attach the fixture to the housing and attach the grille to the fixture with the fastener provided.

6.Screw in a light bulb and attach the diffuser; this will generally just snap in place. Finally, run the ductwork, making as few turns as possible (see above). Mark the location for the vent cap and cut out the hole.

Apply a bead of silicone caulk around the perimeter of the cap and slide it in the opening. Fasten the cap to the wall with galvanized screws. Connect the ductwork to the vent cap and test the system.

Source:http://www.hometips.com/articles/faninstall.html