The answer to 'my zone control system won't turn on' is that there could be several common causes, including a tripped circuit breaker, faulty thermostat, or issue with the zone control panel. The symptoms you may notice include no power to the system, thermostats not responding, or the zone control panel not displaying any lights or indicators.
Some potential solutions you can try include checking the circuit breaker, replacing the batteries in your thermostat, and inspecting the wiring connections to the zone control panel. However, if you're not comfortable troubleshooting the electrical components, it's best to call in a professional HVAC technician to diagnose and repair the issue.