I have a Waterfurnace 5-series, with a closed loop, Intellizone2 zoning. It went online 12/31/2012. The dealer contacted me this year and said that the service plan they include a "free first year maintenance" with the installation. I've not yet made an appointment to have them come out. My question - what should they actually check on this system? It is a 4-ton prepackaged unit. 1. Antifreeze? 2. Freon level? 3. ??? In addition, how much of the "checking" should they (or can they) do with the WF AID tool as opposed to manual checks? I want to make sure that they send a knowledgeable tech, so I want some insight as to how you folks believe this "checkup" should be done. Thanks!