42002-0024S Stack Flue Sensor Replacement | Fits Pentair MasterTemp & Sta-Rite Max-E-Therm Pool & Spa Heaters | New

Pool Heater Throwing an Error Code? This Sensor Is Likely the Fix.

When your Pentair MasterTemp or Sta-Rite Max-E-Therm pool heater shuts down unexpectedly or displays a stack flue sensor fault, the culprit is almost always the stack flue sensor. This aftermarket replacement for part number 42002-0024S is a direct-fit solution designed to restore your heater to normal operation — without the dealer markup. New, unused, and ready to install.

Key Benefits

• ✅ Direct Replacement for 42002-0024S — aftermarket part engineered to replace OEM part number 42002-0024S (also referenced as 420020024S)
• ✅ Fits Pentair MasterTemp & Sta-Rite Max-E-Therm — compatible with pool and spa heater models that use the 42002-0024S stack flue sensor
• ✅ Stainless Steel Threaded Probe — durable stainless construction with hex nut for secure installation into the heater flue port
• ✅ Plug-and-Play Connector — red connector plug and white wire lead match the OEM harness for straightforward installation
• ✅ Restores Heater Function — addresses stack flue sensor fault codes that cause heater shutdown or lockout
• ✅ Brand New, Unused — new aftermarket part, not refurbished or pulled; ships in sealed poly bag

What’s Included

• 1x aftermarket stack flue sensor (stainless threaded probe, hex nut, red connector, white wire lead)
• Compatible part number: 42002-0024S / 420020024S
• Fits: Pentair MasterTemp and Sta-Rite Max-E-Therm pool and spa heaters

How to Install

1. Turn off and disconnect power to the pool heater completely before beginning any work.
2. Allow the heater to cool fully if it has been recently running.
3. Locate the existing stack flue sensor in the heater’s flue assembly.
4. Disconnect the wire harness connector from the old sensor.
5. Unthread the old sensor from the flue port using an appropriate wrench on the hex nut.
6. Thread the new 42002-0024S sensor into the flue port and tighten securely.
7. Reconnect the wire harness to the new sensor’s connector.
8. Restore power and test the heater for normal operation.

Who It’s For

• ✔ Pool and spa owners with a Pentair MasterTemp or Sta-Rite Max-E-Therm heater showing a stack flue sensor fault
• ✔ Pool service technicians performing heater diagnostics and repairs
• ✔ DIY pool owners comfortable with basic heater component replacement

Verify compatibility with your specific heater model and serial number before installation. If you are not comfortable working with gas appliances or electrical components, hire a licensed pool or HVAC technician. Always disconnect power before servicing pool equipment. This is an aftermarket replacement part; More4less Outlet is not affiliated with Pentair or Sta-Rite.

FAQ

Q: What heaters does this sensor fit?
A: This sensor is a replacement for part number 42002-0024S, used in Pentair MasterTemp and Sta-Rite Max-E-Therm pool and spa heaters. Verify your specific model uses this part number before ordering.

Q: Is this an OEM or aftermarket part?
A: This is an aftermarket replacement part engineered to fit in place of OEM part 42002-0024S. It is not manufactured by or affiliated with Pentair or Sta-Rite.

Q: What fault code does a bad stack flue sensor cause?
A: A failed stack flue sensor typically causes the heater to shut down or display a sensor-related fault or error code. Consult your heater’s manual for specific fault code definitions.

Q: Is this brand new?
A: Yes — brand new, unused aftermarket part shipped in a sealed poly bag.

Q: Do I need any special tools to install this?
A: Basic hand tools (wrench for the hex nut) are typically sufficient. Always disconnect power before servicing and consult a licensed technician if unsure.

Confidence Guarantee

Every item ships brand new and unused. If there’s ever an issue with your order, reach out and I’ll make it right.