Zoning & Outdoor sensor I will be installing a new geothermal heat pump later this year and have received a lot of good information on what to be aware of from this site. I have a few items that I am trying to find additional information on and would like to obtain opinions on these topics. For a little background the style of house is a Cape Cod style. The location of the installation will be in Pennsylvania. The unit to be installed will most likely be a Climatemaster Tranquility, closed loop system. 1) I interested in exploring zoning the 2nd floor separately from 1st floor. In addition, I might want to zone the back of the 1st floor separately as well due to solar heat gain. In looking at the controls that Climatemaster offers it does not appear that they have a way to incorporate zoning into the system. Therefore, it appears that a 3rd party controls package would be required. What, if any control packages can you recommend? Is it worth zoning the ductwork? Are there downfalls to zoning? 2) I have noticed that some of the thermostats offer the ability to wire in an external temperature sensor. I know that this is beneficial for boiler applications where the boiler will heat the water to a temperature based on the heating load required while factoring in the outdoor temperature. Does this external sensor provide a benefit for a 2 stage GSHP? Thank you for your help.