Replacement For Pentair 42002-0024S Stack Flue Sensor (2-Pack)

Replacement for Pentair 42002-0024S Stack Flue Sensor, Convenient 2-Pack

Restore dependable exhaust temperature monitoring in your compatible pool or spa heater with the Wholesale Sensors Replacement for Pentair 42002-0024S Stack Flue Sensor, 2-Pack. Designed for select Pentair MasterTemp and Sta-Rite Max-E-Therm pool and spa heaters, this replacement temperature sensor monitors conditions in the heater’s exhaust or flue system and provides important temperature feedback to the heater control system.

This package includes two replacement stack flue sensors, making it a convenient option for professional pool service companies, maintenance departments, property managers, or pool owners who want an additional replacement available for future maintenance.

The Wholesale Sensors replacement is engineered as a perfect OEM replacement that meets or exceeds OEM specifications for fit, function, temperature response, and electrical performance in compatible applications.

Direct Replacement for Pentair 42002-0024S

This sensor is designed as a direct replacement for Pentair part number 42002-0024S in compatible pool and spa heater applications.

Common part number formatting may also appear as:

42002-0024S
420020024S

Always confirm the original sensor part number before purchasing. Pentair has used different temperature sensing components across heater families, generations, and configurations, so matching the existing part number and heater parts diagram is the most reliable way to determine compatibility.

The 42002-0024S should not be confused with the water thermistor or high limit switch. The stack flue sensor performs a different function by monitoring temperature associated with the heater exhaust system.

Designed for Pentair MasterTemp Pool and Spa Heaters

The 42002-0024S stack flue sensor is used in select Pentair MasterTemp High Performance Pool and Spa Heaters.

Compatible applications include popular MasterTemp heater configurations such as select:

MasterTemp 200
MasterTemp 250
MasterTemp 300
MasterTemp 333
MasterTemp 400

Compatibility can vary according to heater generation, production date, fuel type, and equipment configuration. Always verify the complete heater model and existing stack flue sensor part number before ordering.

Pentair MasterTemp heaters combine electronic controls with multiple sensing and safety components to monitor operating conditions. The stack flue sensor provides the control system with exhaust temperature information that helps the heater identify abnormal temperature conditions.

Designed for Sta-Rite Max-E-Therm Heaters

The replacement 42002-0024S stack flue sensor is also designed for select Sta-Rite Max-E-Therm pool and spa heaters using the corresponding sensor configuration.

Compatible applications include select Max-E-Therm:

SR200
SR333
SR400

Additional heater configurations may use the same sensor. Because parts can vary by heater production date and configuration, customers should verify the existing 42002-0024S number before purchasing rather than relying solely on the heater family name.

Monitors Stack and Flue Temperature

The stack flue sensor has an important role in heater operation. Unlike the water thermistor, which monitors water temperature, the stack flue sensor monitors temperature associated with the combustion exhaust system.

During normal operation, hot combustion gases move through the heater and exit through the exhaust system. The stack flue sensor provides temperature information to the heater’s electronic control system.

If the control system receives a temperature reading outside the expected operating range, it may shut down the heater and display a diagnostic indication. This helps prevent continued operation when the system detects potentially abnormal exhaust temperature conditions.

A properly functioning sensor therefore provides important information used by the heater’s monitoring and diagnostic systems.

Helps Diagnose SFS-Related Heater Problems

On compatible Pentair heater systems, a problem involving the stack flue temperature circuit may produce an SFS or Stack Flue Sensor-related fault.

A defective sensor may contribute to symptoms such as an SFS diagnostic indication, intermittent heater shutdown, failure to remain operating, or inaccurate stack temperature feedback.

If electrical testing confirms that the original stack flue sensor has failed, replacing it with a compatible 42002-0024S sensor can help restore accurate temperature feedback.

However, an SFS fault does not automatically mean the sensor itself is defective.

Actual excessive exhaust temperature can result from other heater conditions. Problems involving combustion, airflow, water flow, the heat exchanger, fuel supply, burner operation, wiring, or other components may cause the heater to detect an abnormal stack temperature.

For this reason, proper troubleshooting should be completed before replacing the sensor.

Never Bypass a Stack Flue Sensor

The stack flue sensor is part of the heater’s temperature monitoring system and should never be bypassed simply to keep the heater running.

If the heater is experiencing a genuine excessive-temperature condition, bypassing the sensor could allow continued operation without proper temperature monitoring.

When an SFS fault occurs, inspect and diagnose the heater according to the manufacturer’s service procedures. Replace the sensor only when testing confirms that the sensor or its associated connection is defective.

This replacement is designed to restore the intended sensing function, not override the heater’s built-in monitoring system.

Built for High-Temperature Heater Environments

A stack flue sensor operates in a significantly hotter environment than a standard pool water temperature sensor. For that reason, dependable materials and consistent temperature response are important.

The Wholesale Sensors replacement incorporates a precision temperature-sensing element, durable high-temperature probe construction, insulated wiring, and secure electrical connections designed for compatible pool heater exhaust applications.

The sensor is engineered to withstand repeated heating and cooling cycles associated with normal heater operation while maintaining dependable temperature response.

Every Wholesale Sensors stack flue sensor is rigorously tested for temperature response, electrical performance, consistency, and reliability before shipment.

Straightforward Replacement Design

The direct replacement configuration helps simplify servicing a confirmed defective Pentair 42002-0024S sensor.

Before servicing the heater, disconnect electrical power and fuel according to the manufacturer’s procedures and allow the heater to cool completely. Locate the existing stack flue sensor, inspect its wiring and connections, and compare the original part number with the replacement.

Install the replacement in the corresponding sensor location and ensure the electrical connection is properly secured.

Pool and spa heaters combine electricity, combustible fuel, pressurized water, and extremely hot surfaces. If you are unfamiliar with pool heater diagnosis and service, installation should be performed by a qualified pool heater technician.

Convenient 2-Pack for Maintenance and Service

This listing includes two Pentair 42002-0024S compatible stack flue sensors.

The 2-pack configuration is particularly useful for professional pool service technicians who maintain multiple Pentair or Sta-Rite heaters. It can also provide a convenient spare for facilities, property managers, hotels, apartment communities, and homeowners maintaining compatible equipment.

Each sensor is individually designed to provide the required temperature-monitoring function in compatible heater applications.

Wholesale Sensors Quality and USA-Based Support

Wholesale Sensors specializes in temperature sensors, thermistors, pressure sensors, switches, and replacement sensing components for pool and spa equipment, HVAC systems, appliances, automotive applications, commercial equipment, and other demanding systems.

Our focus on sensor technology allows us to provide carefully tested replacement components engineered for accurate, consistent, and dependable performance.

The Wholesale Sensors Replacement for Pentair 42002-0024S Stack Flue Sensor, 2-Pack provides a practical repair and maintenance solution for compatible Pentair MasterTemp and Sta-Rite Max-E-Therm pool and spa heaters.

Every sensor is carefully inspected and tested before shipment. Your purchase includes two replacement stack flue sensors, backed by a 12-month warranty and responsive USA-based product support.

Whether you are a homeowner maintaining a pool heater, a professional pool technician servicing customer equipment, or a facility manager maintaining multiple heating systems, Wholesale Sensors provides dependable replacement sensing solutions and knowledgeable product support.