From reading through it seems like you've got multiple mats for one area and they're totalling more then 16amps?
We normally say if the total watts in between 3000-3600w then a 20A DP Switch can be used but for anything over 3600 then a contactor would be needed to switch the load.
Running multiple zones on one thermostat can be done however you've got to think about the temperature difference in the zones and where the thermostat is placed.
A kitchen & dining room for example, control them both off one thermostat and place the thermostat in the kitchen. When appliences are on creating heat the thermostat will read that and then kick off leaving the dining room with no heat at all.
We normally say if the total watts in between 3000-3600w then a 20A DP Switch can be used but for anything over 3600 then a contactor would be needed to switch the load.
Running multiple zones on one thermostat can be done however you've got to think about the temperature difference in the zones and where the thermostat is placed.
A kitchen & dining room for example, control them both off one thermostat and place the thermostat in the kitchen. When appliences are on creating heat the thermostat will read that and then kick off leaving the dining room with no heat at all.
