Funmit Flue Temperature Sensor for Pentair Spa Heaters — 42002-0024S Direct Replacement, Stainless Steel Probe

The Funmit 42002-0024S is a direct-replacement stack flue temperature sensor made to restore safe, reliable operation of Pentair MasterTemp and Sta‑Rite Max‑E‑Therm spa and pool heaters.

If your Pentair-style heater shows intermittent shutdowns, safety lockouts or fault codes related to the chimney/flue sensor, this Funmit 42002-0024S replacement part provides a like-for-like repair path. Built with a corrosion-resistant stainless steel probe and heat-protected wiring, the sensor measures exhaust temperature so the heater’s control board can make safe operating decisions. This listing covers compatibility notes, common fault fixes, installation tips and who benefits most from this upgrade.

How will this sensor fix my heater’s fault codes?

The 42002-0024S monitors flue/exhaust temperature and feeds that data to the heater control. If the original sensor has degraded or failed, the control may register errors like E05, E06 or SFS and shut down to protect the system. Replacing the worn sensor with this direct-fit Funmit unit typically clears those faults and restores normal operation when wiring and control board are otherwise healthy.

• Direct replacement for part number 42002-0024S — swap without modifying mounts.
• Targets common error codes: E05, E06 and SFS from flue sensor faults.
• Stainless-steel probe provides stable temperature readings under heat stress.

What features improve durability and long-term performance?

Funmit constructed this sensor to withstand the harsh environment inside a heater chimney. The stainless steel probe resists rust and scaling, while the wiring comes with a heat-resistant sleeve to prevent insulation breakdown. These choices reduce failure from corrosion and heat aging, increasing the part’s service life compared with low-quality alternatives.

• Rust-free stainless-steel probe for corrosion resistance.
• Heat-protected wire sleeve to reduce high-temperature wear.
• Robust connectors and factory-compatible harness for reliable contact.

How do I install the 42002-0024S safely and correctly?

Installation is straightforward for anyone comfortable working around pool heater electrical components, but it should be performed with power off. Remove power at the breaker, note wiring positions, unclip the old sensor, and install the new unit in the same location. If you’re unsure, consult a certified technician to avoid wiring mistakes or safety risks.

• Always cut power to the heater before starting work.
• Match wiring and clip locations to the original sensor — no modification required.
• Wear work gloves to protect hands when accessing the chimney area.

Will this part fit my heater model?

This Funmit sensor is a direct replacement intended for Pentair MasterTemp and Sta‑Rite Max‑E‑Therm electrical systems that used the 42002-0024S original part. Verify your existing part number matches 42002-0024S before ordering to confirm compatibility; if your heater uses a different sensor part number, this unit may not fit correctly.

• Designed as a direct swap for OEM part 42002-0024S.
• Fits Pentair MasterTemp and Sta‑Rite Max‑E‑Therm heater electrical layouts.
• Check your current sensor part number to ensure a match before purchase.

Who is this for? Pool and spa owners, service technicians, and maintenance professionals who need a dependable replacement for a failing Pentair-style flue temperature sensor will find this Funmit 42002-0024S an economical and durable option. It’s best for anyone troubleshooting E05, E06 or SFS-type errors or eliminating random heater shutdowns caused by a worn flue sensor. If you prefer to avoid in-shop downtime, this direct-fit part simplifies field replacement and gets heaters back into safe service quickly.