The answer to 'zone control system making loud noise' is that a noisy zone control system is often caused by a problem with the dampers or actuators. Symptoms may include loud banging, rattling, or screeching noises coming from the vents or air handlers when the system is running. Common causes include worn or stuck dampers, loose components, or issues with the zone control motors and wiring.
In most cases, a noisy zone control system will require professional diagnosis and repair by an HVAC technician. Attempting DIY repairs can be dangerous and may cause further damage. A qualified technician can inspect the system, identify the root cause, and make the necessary adjustments or replacements to stop the noise and restore proper zone control operation.