Lennox gas pack with Honeywell 5000 problem

Hello everyone,

I have a question for the “best” HVAC guru!

I have a Lennox LRP14GE (less than 2 years old) gas pack with a Honeywell 5000 T-stat that a local contractor installed.
A service alert was issued (4 months after the install was done) for incompatibility from Lennox to change out the 5000 to their brand (White Rogers) or Honeywell Vision 8000 model. The 8000 has been installed now but the gas pack will not turn the inducer blower on just like the 5000 didn’t. Breaker had been shut off/on, to “reboot” the 5000 but that procedure would not work on the new 8000. I connected the Red to White wires at the unit and then later at the T-stat to determine “if” the Board was bad. Blower comes on. That tells me that the T-stat is bad and not the board. Right? 4 techs have come out separately and no one can confirm a bad board/relay. But they’ll change out the T-stat, (twice now with the 2nd 8000) the unit will run fine for a few hours and then shut down and send it to a “lock-out” mode. Which is bad? T-stat, board or both now?
Any info is appreciated!

Chris Dobbs