I am upgrading from an old honeywell T841 thermostat to a new Honeywell digital TH5220D. My Heat Pump is a Carrier 38YCB from 1996 On the old T841 thermostat the wires are attached as follows: The Yellow wire attaches to Y. The Green attaches to G. The Orange wire attaches to O. The red wire attaches to R. The brown wire attaches to X. The white wire attaches to W2. On the Heat pump unit the wire connections are the same except the brown attaches to C at the heat pump. The new TH 5220D has the following terminals and designations: Rc for 24VAC power from cooling transformer. R for 24VAC power from heating transformer. R and Rc are bridged together. O/B for changeover valve. Y for compresser contactor (stage 1) G for fan relay AUX for auxilary heat relay E for emergency heat relay L for sends output when set to emergency heat. C for 24VAC common. C is optional with batteries. How do I connect the new thermostat.

I just added a P trap to the condensate drain outlet, as per manufacturer installation and operating instructions on page 9, http://www.smarterwayinc.us/refLIB/Goodman/1255/aruf/IO-230.pdf,on the airhandler. The original installer omitted this for some reason. As the drawing reveals, there are two drain outlets. The one on the left is being utilized. However, the drain outlet on the right is capped off. Should this drain outlet remain capped or am I missing something? Goodman Heat Pump AEPF-4260 VSM Air Handler CPLT-60 Condenser Air handler & condensate drain configuration: http://i205.photobucket.com/albums/bb140/mjbxx1999/drain.jpg