Perhaps you've moved house and there's no instruction manual for your unit? (This is also an ideal time for a clean and check!)
A Manual Controller is fairly straightforward, but are you getting the best out of it? Is your Networker, controlling different zones in your house, working efficiently? Or has the mode setting on your controller accidentally been tripped into Auto?
During a service call, I can show you how to use the controller and set it up for optimum operation.