Dometic™ Atwood 31094MC Aftermarket RV Furnace Air Flow Sail Switch

This is a replacement sail switch for select Atwood and Dometic Furnaces. Designed to ensure the proper operation of your RV furnace's blower motor. The sail switch is an important safety feature that detects air flow and verifies that the blower motor is functioning properly before allowing the furnace to ignite and begin heating the air.

When the paddle of the switch is depressed, there should be continuity through the switch. If a sail switch needs to be replaced, it should be replaced with the exact same size. The most common problems with these switches are bent paddles, loose wire connections or an obstruction between the paddle and switch contact.

To test the sail switch set a multimeter to the continuity setting and attach one lead to each of the switch's terminals. With the switch in the closed position, the multimeter should indicate continuity. Then, blow air into the sail switch and watch the multimeter. The switch should open and break the continuity. If the switch fails to open, it is likely faulty and needs to be replaced.

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.