62-23543-01 – FLAME SENSOR (RHEEM)

If your furnace lights but shuts off after a few seconds, a dirty or failed flame sensor is the most likely cause. This sensor replaces the Rheem 62-23543-01 and fits Rheem and Ruud furnaces in the RGPH and UGPH series.

Replaces: 62-23543-01, FLS301

Fits: Rheem/Ruud: RGPH-10EBRJR, UGPH-10EBRJR

Need help? See our Furnace Not Heating Guide.

In stock at Open To Public HVAC Parts in Dallas. We test parts at the counter before you buy. Call or text (214) 340-9421.

Specs

• TypeFlame rectification sensor
• MaterialKanthal alloy rod
• MountSingle-screw bracket (verify with old part)
• Typical Reading2-6 µA DC (microamps) when sensing flame
• VersionRheem OEM

Cross-reference numbers

This part replaces the following OEM and aftermarket numbers:

• 62-23543-01
• 62-23543-02
• 62-23543-03
• 62-23543-04
• 790-843A1
• FLAME-SENSOR
• RGPH-10EBRJR
• UGPH-10EBRJR

Not sure if your number matches? Call (214) 340-9421 or bring the old part in — bench-testing is free.

Fits these models

• Rheem Classic Series gas furnaces (RGRA, RGFD, RGLE families)
• Ruud Achiever Series gas furnaces (UGRA, UGFD, UGLE families)
• Most Rheem / Ruud gas furnaces from late 1990s onward
• Verify bracket geometry matches your existing sensor before swapping

How do I clean a flame sensor?

Pull the sensor (usually one screw), rub the metal rod with fine emery cloth or a green Scotch-Brite pad until it's bright silver. Don't use sandpaper coarser than 600 grit. Reinstall, fire the furnace, see if it stays lit.

How do I test a flame sensor?

Put a DC microamp meter inline between the sensor and the control board. With flame present, you should read 2-6 µA. Below 1 µA = dirty or dead — clean first, then replace if cleaning doesn't help. Bring it to the counter, we test free.

How long should a flame sensor last?

5-10 heating seasons typical when kept clean. Hard-water condensate, high-mineral combustion air, or short-cycling all shorten it. Most flame sensor "failures" are just dirty buildup — clean before replacing.