I have a Trane heat pump, model # TWV025B140A1. And a Hunter 44760 thermostat I want to install as I my other one is going bad. Here is the wiring diagram coming off my old thermostat. G green Y yellow E black O orange X1 blue W2 white R red And there is a brown wire not connected to anything. Wiring diagram off the new thermostat R 24V ac supply Y1 Compressor stage 1 W2 Aux heat E Emergency heat O Reversing valve cooling mode B Reversing valve heating mode G Fan L System monitor C 24v ac common The first thing that jumps out at me on the cross reference chart that came with the thermostat says that on a trane heat pump that B is the 24 v common, there isn't a wire hooked up to B on the old thermostat. What can be done about that? And last if the 24v common wire problem can be fixed, would it be hooked up like this on the new thermostat R-Red Y-Y1 W2-White E-Blue O-Orange G-Green And where does the black wire go that was connected to E? The cross reference chart can be found at this website on page 7. http://www.hunterfanhq.com/tools/sales/hunter/preseason/images/owners/44760.pdf Thanks in advance for any advice, Chris

Plenum sits above the Air handler & it sits on a Return Air Box. Return Air Box is 40" total height (that is 18" above subfloor and 22" below subfloor) I have three 10" return ducts connected to the return air box below the subfloor. Can I install a return duct line into the return air box above the subfloor for more return air in an adjoining room? In addition, would this new return line adversely affect the original three return ducts below the subfloor? The reason I am considering this is because there is no return air vent in the living and dining rooms of the house.