Home Depot, VentingDirect.com and ATG Stores all sell replacement bathroom fans. Fans are available with and without ceiling lights and with a wide range of fan speeds and other variables, depending on what the other fixtures in the bathroom already offer.
The retailers offer detailed information about the various types of bathroom fans on their websites. The maximum square footage recommended for the bathroom is particularly helpful so the consumer gets proper ventilation from the equipment. Other information includes the speed of the fan in terms of air volume cleared per minute, available colors, sound level of the fan in sones, and whether or not the light and fan sense humidity and motion. The dimensions, mounting style, existence of a nightlight, number and type of bulbs required, presence of a remote control or timer, and the terms under which the fan can be returned all appear.
Other project specifications include the size and shape of the duct, ENERGY STAR certification, compliance with Title 24, UL listing for installation over a shower or tub with a GFCI circuit, and whether or not the fan has a plastic damper. The VentingDirect.com pages include a general product overview that includes the particulars of installation as well as the reputation of the manufacturer.