I am finding this error in the simulation error referred to some of my thermal zones.

I have checked here and here: I looked at all of my thermostats (which are fine) and I do not have any cooling cabinet in my model. I used also the procedure illustrated here to assure the ACH for every zone are mantained. The errors I get are

   ** Warning ** Calculated design cooling load for zone=THERMAL ZONE: F2-OR 2 is zero.
   **   ~~~   ** Check Sizing:Zone and ZoneControl:Thermostat inputs.
   ** Warning ** Calculated design cooling load for zone=THERMAL ZONE: F2-OR 3 is zero.
   **   ~~~   ** Check Sizing:Zone and ZoneControl:Thermostat inputs.
   ** Warning ** Calculated design cooling load for zone=THERMAL ZONE: F2-OR 4 is zero.
   **   ~~~   ** Check Sizing:Zone and ZoneControl:Thermostat inputs.
   ** Warning ** Calculated design cooling load for zone=THERMAL ZONE: F2-OR1 is zero.
   **   ~~~   ** Check Sizing:Zone and ZoneControl:Thermostat inputs.
   ** Warning ** Calculated design cooling load for zone=THERMAL ZONE: F4-TRASPLANT OR is zero.
   **   ~~~   ** Check Sizing:Zone and ZoneControl:Thermostat inputs.
   ** Warning ** Calculated design cooling load for zone=THERMAL ZONE: F6-CARDIAC OR is zero.
   **   ~~~   ** Check Sizing:Zone and ZoneControl:Thermostat inputs.
   ** Warning ** Calculated design cooling load for zone=THERMAL ZONE: SF1-ANGIOGRAPHY is zero.
   **   ~~~   ** Check Sizing:Zone and ZoneControl:Thermostat inputs.
   ** Warning ** Calculated design cooling load for zone=THERMAL ZONE: SF1-TAC is zero.
   **   ~~~   ** Check Sizing:Zone and ZoneControl:Thermostat inputs.
   ** Warning ** Calculated design cooling load for zone=THERMAL ZONE: SF2-DRESSING ROOM is zero.
   **   ~~~   ** Check Sizing:Zone and ZoneControl:Thermostat inputs.
   ** Warning ** ManageSizing: For a plant sizing run, there must be at least 1 Sizing:Plant object input. SimulationControl Plant Sizing option ignored.

What can cause this kind of warining? Shall I ignore them since the simulation runs? I do not think it would be great to ingore them since they are sizing-error-related warnings.