I use PLC's, washer fluid, and air to winterize both TF and FB...Here is a thread I started a few years back. Pictures at post 75...So far its been pretty flawless and super cheap to operate. Last winter I used less than 20 gallons washer fluid. Lots cheaper than weeping water out of two LP hoses!
http://www.autocareforum.com/showthread.php?8291-Programmable-Relay-or-PLC&highlight=programmable
http://www.autocareforum.com/showthread.php?8291-Programmable-Relay-or-PLC&highlight=programmable