Exhaust Thermistor Kit (W/ O-Ring And Screw)

RTG20319P Exhaust Thermistor Kit – Accurate Flue Gas Monitoring for System Protection

The Rheem RTG20319P is a factory-supplied exhaust thermistor assembly used in select Rheem tankless gas water heaters. This sensor monitors flue gas temperatures and provides critical input to the system’s control board to ensure safe operation. It enables over-temperature shutdowns and maintains compliance with thermal protection parameters.

This OEM kit includes the thermistor, mounting hardware (retaining screw), and sealing O-ring to ensure a secure, leak-free installation. It is designed for direct replacement of original equipment in compatible Rheem models.

Function and Use

• Continuously measures exhaust gas temperature to protect heat exchanger and flue components
• Communicates with the system's control module to trigger high-limit safety responses
• Required for proper burner modulation based on temperature feedback

Kit Components

• ✔ Exhaust thermistor (sensor lead with connector)
• ✔ OEM O-ring for seal integrity
• ✔ Mounting screw for thermistor housing

Technical Specifications

• Part Number: RTG20319P
• Sensor Type: Thermistor (NTC – Negative Temperature Coefficient)
• Installation Point: Flue gas outlet or heat exchanger exhaust path (location varies by model)
• Compatibility: Select Rheem RTG series tankless gas models (confirm via model number)

Installation Notes

This component should be installed by qualified personnel due to its role in system safety. It connects via the internal wiring harness and must be installed with attention to orientation and thermal contact. Improper installation may cause inaccurate temperature readings or system lockout.

Inspect the O-ring for proper seating to prevent exhaust gas leakage. Always test system response post-installation and verify that error codes are cleared.

Professional Considerations

• Match thermistor part number to model-specific documentation
• Ensure undamaged harness connector and proper wire routing
• Test thermistor resistance at ambient temperature to verify calibration before service completion

Key Advantages

• ✔ Critical Safety Component – Supports overheat protection and system regulation
• ✔ OEM Fit and Calibration – Engineered for precise signal compatibility with Rheem control logic
• ✔ Service-Friendly Kit – Includes mounting and sealing hardware for direct replacement