Hi shifrbv, Thanks for the response. So the only thing that will hook the gas furnace (as secondary/emergency heat) to the tstat is running W from the furnace to W2 on the tstat? What do I hook the W wire from the HP to on the tsat? Its doesnt hook into the O/B terminal with the O from the HP does it? It appears as though the W & O/B share a terminal on the tstat! Also (your last sentence) what did you mean by setting the defrost cycle to DP on the Heat Pump? What is DP? Also would the setup mode I am trying to run be considered multi-stage Heat Pump or Conventional multi-stage system? I assume it would be the latter? Correct? Since I am going to have a W and W2 for heat stages and Y for cooling stage. Thanks for your patience and time, I am new to alot of this so I know its difficult dealing with those like me who know so little in this field... I could let you see pictures of the terminal contact points on all of my components if that would help you understand what I am working with here ... I have schematic of hp as well.

I think the wall plate should not be a problem but it should just be a 5 minute job to swap the wall plate anyway. Take your old stat off and GENTLY plug it in to the new wall plate and see how things line up and that should answer your question. If you just purchased the stat alone I would say you will be good to go. If you have a new module for the furnace/air handler I would attempt to check to see if there was any revisions between the two units. I would think you would be good to go but there might be some revision that would be beneficial. Either way should work just fine.

The wiring diagram on page 8 of the installation instructions (which appears different than the one at bit of which is included on the photo you posted) shows a door switch so, as suggested above, you might want to check whether that switch is closed. Also, with that switch closed, you might check for 24 volts between the XFMR-R and XFMR-C terminals on the circuit board. And, I think, between the R and C terminals on the circuit board.

mike_home 21 hours ago A new reason not to do a load calculation. A new reason to "manipulate" the outcome. For every ying there is a yang, Mike. Many on this board like to only look at a single thing--- when the whole picture is blurred lines. A heat load for heating or cooling is an estimation based on how hot or cold someone estimates a certain climate to be. It's not always that hot or cold, that number is a moving target... none of you that profess the nature of this calc can yet see the forest from the trees on this subject. The proper estimate is over sized 90% of the time. That is the *cost* of being correct. Let's not think about that. Some of you are faintly starting to get it because of the "size you need" won't be available or the sizes in that realm are hard to come by. So under those conditions, throw out the calc and go with your gut? So if you throw out the calc numbers (or manipulate said numbers) what is the point in doing the actual calculation? To give to the so and so's who require it in a given area? If you lack the experience --- what your gut tells you? Make it up. Anyone can be a HVAC genius, no schooling, just go on line pick a calc, pick a forum board, get a few basic ideas and demand that heat calc is a proper method to give you an exact number in a world of various numbers due to "what ever other reason" you know whether it be the mythical we're gonna die due to climate change, global warming, a new global ice age etc. Live in a mild climate vs a cold climate vs a hot climate. The real world isn't a static number that never changes. But the myth is to deny all these disparities and say the calculation will make or break you. Certainly it can... both ways --- doing the calc or not doing the calc - That decision is where "EXPERIENCE" plays it's role. Some one who actually does this for a living tells you (based from experience of actually doing this for me that is 28 years as of now) a heat load is not what it's cracked up to be when just relying on the calculaiton alone, it's an estimation - that is all. An educated guess, but only when base on that experience the tool is needed to come out of the tool bag. Then realizing the function in which it plays. (It's not an exact science... to get exact it now comes down to equipment selection -- modulation when it comes to gas furnaces and inverters when it comes to AC's & Heat Pumps.) This type of HVAC equipment for some climates comes at a cost -- just to say the heating and or cooling system is properly sized every time the system turns on. The heat load calc will never get you there on it's own. GIGO: Garbage in Garbage out - exactamundo. It's an excuse not to do one / It's an excuse to manipulate it. (in case you missed it)