This replacement sail switch is specifically designed for Atwood and Dometic Furnaces, ensuring the proper functioning of your RV furnace's blower motor. It serves as a crucial safety feature by detecting air flow and verifying the blower motor's operation before igniting and heating the air.
The sail switch should have continuity when the paddle is depressed, indicating its proper functioning. If a replacement is necessary, it is important to choose the same size switch. Common issues with these switches include bent paddles, loose wire connections, or obstructions between the paddle and switch contact.
To troubleshoot the sail switch, use a multimeter set to the continuity setting and connect one lead to each terminal of the switch. When the switch is closed, the multimeter should show continuity. Blow air into the sail switch and observe the multimeter. The switch should open, breaking the continuity. If it fails to open, it is likely defective and requires replacement.

Compatibility:
Atwood Furnaces: AFSD20111, AFSD20121, AFSD20131, AFSD20141, AFMD25111, AFMD30111, AFMD35111, AFMD25121, AFMD30121, AFMD35121, AFMD25131, AFMD30131, AFMD35131, AFMD25141, AFMD30141, AFMD35141, AFMD25151, AFMD30151, AFMD35151, AFLA35211, AFLA40211, AFLD35111, AFLD40111, AFLA35221, AFLA40221, AFLD35121, AFLD40121, AFLA35231, AFLA40231, AFLD35131, AFLD40131
Please be aware that there is no precise serial number distinction indicating the transition to the flat blade style in Atwood models. It is advised to compare your existing sail switch with the product image for verification. In case your switch matches the flat blade version, you should order part number 36165

Dometic Furnaces: Models DFMD16111, DFMD16121, DFMD16131, DFMD16141, DFMD16151, DFMD20111, DFMD20121, DFMD20131, DFMD20141, DFMD20151, DFMD25111, DFMD25121, DFMD25131, DFMD25141, DFMD25151, DFMD30111, DFMD30121, DFMD30131, DFMD30141, DFMD30151, DFMD35111, DFMD35121, DFMD35121W, DFMD35131, DFMD35141, and DFMD35151 with serial numbers 72489156 and below.
Models DFLD35111, DFLD35121, DFLD35131, DFLD40111, DFLD40121, and DFLD40131 with serial numbers 7299127 and below.
Models DFLA35211, DFLA35221, DFLA35231, DFLA40211, DFLA40221, and DFLA40231 with serial numbers 81689155 and below.

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