I have recently installed the G71MPP with the Lennox Series 7000 thermostat with external sensor. I'm experiencing the problem you related to in your original post; that is, the recovery issue. The thermostat has a setting called "Smooth Set back" It's function is to start the furnace up to 2 hours in advance to achieve the termperature set at the event time selected. Unfortunately, the furnace never starts early enough to achieve the temperature selected. I've had numerous discussions/visits with my dealer. This thermostat is so new and so complicated, that it has the technicians guessing as to what the correct settings should be to correct the problem. At this stage I'm totally furstrated. However, I think you're stuck with using this thermostat if you want the benefits of the variable response built into the furnace. That is it will run from 40% to 100% input in 10% increments to maintain the temperature. I don't think the Honeywell would support this function fully. In terms of heat rise, The manual says 12 degrees F per hour but I don't believe it is anywhere near this. This is largely dependent on external conditions. I haven't had the system long enough to fully assess heat rise.

I have a 2-level condo unit that will be a 2-zone system (through the use of 1 furnace and a damper system). My contractor uses Rheem produts, sop I'm looking at the Rheem RGFD Modulating Upflow furnace. Does a this type of furnace work well in this 2-zone setup, or should a traditional "on/off only" furnace be used for this application? It seems to me that you're asking for 2 independent systems (Damper position AND Fan position) to make decision based on temperature. Does this work? Wouldn't there would be 2 thermostats, sending information to the Damper Brain and to the Fan Speed Brain. Do they work together??? I can't figure out how it would work. Thanks.

Not sure I understand most of your questions. It will start on 100% for 30-60 seconds then drop back. Not sure how far, some based on past cycles, some based on temp drop. I'm not sure what all logic goes into its thinking but it won't do anything that will overheat the house. Also not sure of the logic that goes into blower speeds but during start up the units to full hot and checks to see what speed is needed to maintain 65� temp rise. Then as the firing rate changes, the CFM changes as the board deems necessary. Current Rheem coils are all TXV. I wouldn't worry about a freeze stat.

Quote: My experience is that the effect of warm air rising and cold air sinking tends to mess with the effect of the multiple zones. In the summer time the upstairs thermostat calls for cooling while the downstairs thermostat does not but because the cold air sinks the basement and first floor stay cooler than the second floor. End Quote. It will to one degree or another, however a zone system is designed to 'minimize' this problem by controls that direct the cooling or heating to where you want it. Naturally the upper levels of the home will call for cooling more frequently than lower levels. Zoning isn't entirely perfect, in many cases it depends on the home layout. If you have a home that is more 'open' you will get bleed thru from one zone to another. But what difference does it make if you have better control? Assuming of course the zone system is installed properly... many times they are not. The best control of a zone is a zone in which there are 4 walls and a door and preferably there is a return as well as supply duct(s) within that zone. On a multiple level home that is zoned the equation changes some what in that each level of the home is typically a zone. Sure the bottom levels of the home will be cooler than the top level (second floor). The idea in zoning the AC to the basement is to 'limit' the amount of cooling it receives... otherwise the complaint is always the 1st level is too warm and the basement is too cool. Zoning is merely to give you better control and reduce complaints. The other thing that you may not realize is that zoning has the capability to cool one area while heating another area. Not at the same time of course with one HVAC system, but it can vary the cycles. It's all about comfort and control when it comes to zoning. (Think of a yuppie 3 level home with only 1 HVAC system.) Without zoning can you imagine the fights of the lower level of a 3 story home with 1 HVAC system in fall and spring seasons with someone who is on the 3rd level? Savings can be achieved by only cooling or heating areas of the home that need it.