I have a customer trying to get 2 thermostats one for up and then down for one hp system... the problem is house is finished and she has a heat pump system.. We have talked with just turn one off when heat season or cooling is in... vice versa... but not real professional. Curious if anyone had any ideas and schematics for ways to do this without putting zone dampers in system. Her problem is gets too hot in summer upstairs and too cool downstairs in winter... Any help would be nice! Thanks... Brian

Sounds like an airflow problem, run the blower continuously and adjust the dampers to put the air where you need it open and close return ducts on lower levels to make the 2nd floor pull harder,

This constant motion of the air will continue to remix and eventually balance the conditions.

My home is a 4 level split, so its 82 in the top floor while its 62 in the basement

Simply by flipping a fan switch on the t-stat, I have only 1 degree per floor difference now