ZoneFirst ZPS Zone Plenum Sensor

The ZoneFirst ZPS Zone Plenum Sensor is a critical duct-mounted sensor designed for accurate supply air temperature monitoring in both residential and commercial HVAC zoning systems. This plenum-rated temperature sensor integrates directly with MasterZone control panels to safeguard the heat exchanger and cooling coil. By providing real-time data to the panel, the ZoneFirst ZPS prevents equipment damage caused by excessive heat or freezing conditions—common issues in systems with bypass ducts or restricted airflow during zone cycling.

For high-performance HVAC equipment protection, the ZPS features a precision thermistor that detects temperature spikes or drops. The MasterZone panel then uses these readings to manage the equipment calls, typically locking out heating if temperatures exceed a set threshold (often 100°F to 170°F) or disabling the compressor if cooling drops too low (fixed at 45°F). This zoning system sensor ensures that conditioned air continues to reach active zones while the unit resets, maintaining efficiency and preventing short-cycling. Installation requires a simple 1/2-inch hole in the supply duct, downstream of the coil but upstream of any dampers, using the two provided wires for seamless connectivity.

• Enhanced Equipment Safety: Actively monitors for high and low limit conditions to protect compressors and heat exchangers from airflow-related failures.
• Universal Panel Compatibility: Designed for effortless integration with all ZoneFirst MasterZone panels, including the MMP2 and large-scale zoning hubs.
• Advanced System Control: Facilitates adjustable set points on the control board, allowing technicians to fine-tune supply air temperature thresholds based on specific equipment specs.
• Durable Construction: Built to withstand the harsh, high-velocity environments of the plenum while maintaining calibrated accuracy.
• Technical Efficiency: Simplified two-wire installation reduces labor time, and the 10°F reset delta prevents erratic equipment cycling.

Where is the best location to install the ZPS sensor?
Place the probe in the main supply air duct, downstream of the evaporator coil and heat exchanger but before the bypass duct or any zone dampers. Avoid placing it in direct line-of-sight with the heating or cooling sources to ensure the most accurate air temperature readings.

Is shielded cable required for the ZPS wiring?
Standard two-conductor wire is sufficient for runs under 15 feet. However, if the wire run exceeds 15 feet or passes near high-voltage lines, using shielded cable is recommended to prevent electromagnetic interference from affecting the temperature signal.

What happens if the ZPS detects a temperature limit?
The MasterZone control panel will temporarily lock out the heating or cooling equipment. The calls from the thermostats remain active, and the fan continues to run to move air until the plenum temperature returns to a safe range, at which point the system automatically resumes operation.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.