The 78W & 78V are switches that will work with this fan, but they are not timer switches. They are variable speed control switches. Other switches that will work with this fan are:
Of the switches listed above, the ones that are timers are:
All of them can be viewed on our website, www.broan.com. They are all listed under the Bath Fans, Accessories. There are several pages of accessories so you may have to look or you can type in the model number into the search field and go right to the one you are interested in.