PLEASE HELP

keyote

I am renovating one floor at a time switching from old cast iron to new radiant and new boiler, this entails some temporary work arounds on the new system.

I have a taco zone control panel zvc406exp.and a KHN085 with indirect dhw
i want to combine two thermostat zones to both control the same zone valve that feeds a manifold both thermostats are heated from. can i simply put both tstats wires into the same tstat terminals on the panel, and they will then both operate the zone valve ?

1] if the two tstats are ganged will they interfere with each other, if say one is on, then the second comes on, or if both are on and one get satisfied before the other? once the valve is open both areas will get flow, i expect they will have close requirements so dont expect overlap to be a problem as overheating.as long as they cant shut off the other call too soon or short circuit.they are two almost identical apts on same floor.originally hoped to use actuators on each loop but loads are too small.

small loads brings up second problem both apts combined may still be too small a load, so i want to set it up so whenever they call for heat the zone valve for the cellar finn tube opens up as well as a sort of buffer load it wont have a thermostat on it.whats best way to make that happen ? jumper wires between two zones in zone panel?

thanks