I have had 3 dealers come out to give me estimates on 2 new systems. I have also called the local Trane distributor ... it seems that I can easily get 4 different answers to most of my question - when in fact ONLY one answer should be correct. So ... I am still in search of the 'correct' answer.
XV80 Furnace ... Thermostat ... Variable Speed .... 2-stage ... XL14i AC
I basically understand how the 2-stage furnace operates when a single stage thermostat is used ... 1st stage heating is used, if the temperature set pont is not obtained within XX minutes, stage 2 kicks in.
Now ... what if I have a 2-stage thermostat (say the Trane one - XL800) ... do I get additional function and features for 2-stage operation??
If I do use a 2-stage thermostat, will my existing 4-wire system handle it? Or is an additional wire needed for the 2nd stage heating in this case.
What about variable speed? Half the answers said that they dont know if the variable speed still works with an existing OLD thermostat ... the other half stated that I would lose the variable speed feature, but they don't know why. Some also said I can use my 4-wire system with the XL800 thermostat and have proper variable speed operation and 2-stage operation.
And another says that I can use the XL800 that has the humidity sensor and have complete humidity via the variable speed fan.
And exactly how does the variable speed work and what does it buy me? One says is is just a marketing gimmick and does nothing. One says I can get total humidity control. One says that it just ramps up the speed and that it only is variable during the ramp-up. The other didn't know.
So ... does anyone REALLY know the answers to the above?
1) 2-stage thermostat needed and what does it buy me
2) Existing 4-wire system for the new thermostat
3) Variable speed feature loss without a new Trane thermostat
4) Variable speed operation
5) Is the XX time for 2nd stage cut-in adjustable
It is amazing that 4 Trane "expert" dealers and distributors do not know how the system works. It sure doesn't give me a lot of confidence in finding a competent installer.
Oh .. and why not ask Trane? I sent them 3 "contact us" emails ... and finally found a phone number where someone will be getting back to me. So far I am still waiting and waiting.
Thanks .... George