Vertical venting is the best way to vent a pellet stove. Here
DuraVent - PelletVent 3 & 4 Inner Diameter Vertical Cap - 3PVL-VC — Fireplaces USA
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Pellet stoves with vertical vent capability
How To Install Vertical Venting For A Pellet Stove
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DuraVent PelletVent 3 in. Stove Pipe Kit 3PVL-KHA - The Home Depot
The Rock-Vent Pellet Pipe Chimney Cap is constructed from 304L stainless steel. Finish your Pellet Pipe vertical install with this long-lasting cap.
Rock-Vent Pellet Pipe Vertical Rain Cap
EMPIRE Venting Kit for Fireplace Flue EMPIRE Vent Kit – US Fireplace Store
Pellet Stoves: Inserts, Freestanding Stoves, Costs & More - This Old House
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