About Master Flow™ 12‑Hour Timer

The GAF Master Flow™ 12 Hour Timer, when installed on GAF Master Flow™ Belt Drive and Direct Drive Whole House Fans, can be set for any time from 10 minutes to up to 12 hours. When installing with Direct Drive Fan Model, you must have the BWS2 2 Speed Fan Control Switch as well. The timer automatically turns off when time has expired. The timer knob and gray finish wall plate are included. Detailed installation instructions and diagram included.

Features & Benefits

Get automatic Lifetime Protection on your entire GAF roofing system

When you install any GAF Lifetime Shingle and at least 3 qualifying GAF accessories, you'll automatically get a Lifetime limited warranty on your shingles and all qualifying GAF accessories*.
*See GAF Shingle & Accessory Ltd. Warranty for complete coverage and restrictions. The word “Lifetime” refers to the length of coverage provided by the GAF Shingle & Accessory Ltd. Warranty, and means as long as the original individual owner(s) of a single-family detached residence [or the second owner(s) in certain circumstances] owns the property where the shingles and accessories are installed. For owners/structures not meeting the above criteria, Lifetime coverage is not applicable. Lifetime ltd. warranty on accessories requires the use of at least three qualifying GAF accessories and the use of Lifetime Shingles.

Product Documentation

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