Resistored Design: Integrated resistor extends tank life by mitigating electrolytic corrosion

Direct submersion is not recommended

Whether used for permanent monitoring or temporary diagnostics

This SPST normally closed switch serves as the primary protection against heat exchanger overheating

While often used for diagnostics

Zonefirst OAS Air Sensor Resistored Design: Integrated resistor extendsFor veteran technicians managing dual fuel HVAC systems, the ZoneFirst OAS Air Sensor is a critical component for achieving precise balance point control. This outdoor air sensor is engineered specifically to integrate with ZoneFirst H32, H32P, and MDP3 control panels, providing real time ambient temperature data to the fossil fuel heat pump logic. By utilizing a high accuracy thermistor housed in a UV stabilized polycarbonate enclosure, the OAS