I live in South Florida and just had a Trane 5-ton XL19i unit installed a week ago. I also installed the matching 2 stage variable speed air handler along with the Trane TCONT802 thermostat. The system is configure for Comfort-R enhanced mode.
I have noticed that, starting in the early afternoon well into the night, the system runs constantly on the first stage. I have the tstat set point at 77, the outdoor temp is around 95. Yesterday, the system ran on the first stage from 2pm to 10pm. The problem seems to be a function of the thermostat because whatever temperature I set it at, it will maintain it. What I don't understand is why it won't turn off. Is a system more efficient running for 8 hours of the first stage rather than cycling for that same time period?