No, it is not necessary. Each zone's mSense and zone valve (or thermal actuator) can be mapped to different devices.
While we typically wire each zone’s comfort sensors and zone valves to the same mZone module for consistency, there are situations where it’s beneficial to wire the devices to separate mZone modules.
For instance, consider a two-story home using two separate mZones for each floor. All mSense comfort sensors would be connected (“daisy-chained”) to the mZone of their respective floor. However, a zone on the second floor might have a hydronic terminal (e.g., one fan coil) piped to the manifold serving the first floor. In such a case, the mSense would be wired to the second floor’s mZone, while the thermal actuator would be mounted on the first floor’s manifold and wired to the first floor’s mZone. This approach avoids the need to run an extra set of wires from the mZone dedicated to the second floor.
Therefore, even if the mSense and thermal actuator connect to different mZones modules, Messana Controls can still monitor mSense measurements with one mZone and control the respective thermal actuator using the other mZone. This approach minimizes wiring/piping distances, facilitating easier system installation.