TUH2B060A9V3VA 95% gas furnance, 2-stage.
4TTX4036A1000A Condensor, 15 SEER, single stage, 3/8 x 7/8 x 40' lineset
Honeywell TCONT802 2 stage Thermostat
This Trane system was installed a couple days ago. I don't believe they wired the thermostat correctly. I peeked at its service settings, and the thermostat was configured for 2-stage heat (code 0170=7). But they wired it for 1-stage heat instead (thermostat's W2 wire is not installed).
The Furnace's controller board is strapped for 10-minute timer 2-stage operation. So, instead of using the intelligence of the thermostat, they are relying on the furnaces fixed timer instead.
I also noticed that they had the thermostat stage-1 and stage-2 heat setup as a <90% furnace (code 0240=5 & 0250=5). I believe that these should be changed to code 3 (>90% efficiency furnace). Is that the right thing to do?
So, in case there is a Trane installer on the forum, can you advise me on why they would have set up the furnace as summarized here? Would I be better off to rewire the thermostat so that it controlled the second stage rather than the fixed timer method?