When you state, "The 16I should be able to maintain a comfort level on its own without going to W2", is W2 my 2nd stage of gas heat?
This is my first winter with the new system so I don't know how much I'll need that "4th stage of heat (2nd stage gas)". Are you saying that I will generally only need my heat pump and then when it's below my balance pt setting / compressor lockout (30 degrees now) that I will only need/use the first stage of gas furnace? Is that saying that the longest I will ever run my gas furnace in the winter is 10 minutes (since after 10 minutes the control automatically switches to 2nd stage and then off)?
What is controlling the 1st and 2nd stage of the gas furnace with the 803? Is it just run on 1st stage for 10 minutes and then switch to 2nd stage until the set point is reached? Even if I never need 2nd stage, do you think I will ever need to run the furnace longer than a 10 minute cycle?
Would the IAQ allow me to run the 1st stage heat longer than 10 minutes if necessary? Is this a desirable advantage for comfort and longevity of the system (longer cycles)?
I was not aware that the dehumidfication control on the 803 was the same basic process as the IAQ. If the IAQ really just overcools versus some slowing of the blower that will remove humidity and not overcool then that wouldn't be a factor arguing for replacement.
Thanks again for everyone's comments. I'm really learning alot from this forum.
If your system is properly sized you will want to control 2nd stage from the t-stat.
If your design temp is 5*. When the outdoor temp gets closes to 5* do you want to wait 10 min for the furnace to produce the correct amount of heat? If the furnace is grossly over sized (like most are) then it will not matter much.
"We'll have to outwit the fiend with our superior intelligence." Yukon Cornelius
Some people are like Slinkies---not good for anything, but still bring a smile to your face when you push them down the stairs!
How long your system will run on first stage has several factors to consider. We know that you have chosen 30 degrees as your balance point, you may be able to go lower depending on the condition of your house.
I would hate for you to spend money on something and not get any different results than what you already have. Your gas furnace on first stage is 52k your heat pump is 36k under ideal conditions. First stage of your gas furnace will probably satisfy most of the time without going to second stage. Depending on how well your house is insulated and sealed will yieled the run time, along with how well your dealer set up your system. I could not read the label on your picture that was posted to be able to tell you about your installer.
Your furnace control board when it gets a simultaneous call for W1 and W2 will run for 10 minutes in first stage, and then switch to 2nd stage. That could be changed with a simple relay if need be.