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Condensation at roof, down outside of furnace/water heater vent. What is happening? - Home Improvement Stack Exchange
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Oatey 3-in to 4-in x 4-in PVC Vent and Pipe Flashing in the Vent Pipe Flashing department at Lowes.com
![Selkirk 4-in x 8-in Galvanized Steel/Aluminum Cap for Natural Gas Venting - UL Listed, 15-Year Warranty in the Galvanized Pipe & Fittings department at Lowes.com Selkirk 4-in x 8-in Galvanized Steel/Aluminum Cap for Natural Gas Venting - UL Listed, 15-Year Warranty in the Galvanized Pipe & Fittings department at Lowes.com](https://mobileimages.lowes.com/productimages/2819165f-8bcc-4af9-8786-4b366173c168/64197573.png?size=pdhism)
Selkirk 4-in x 8-in Galvanized Steel/Aluminum Cap for Natural Gas Venting - UL Listed, 15-Year Warranty in the Galvanized Pipe & Fittings department at Lowes.com
![How to Fix a Leaky Gas Flue Roof Vent - locate and fix a gas furnace roof vent leak with photos. | Roof vents, Roof problems, Leaking roof How to Fix a Leaky Gas Flue Roof Vent - locate and fix a gas furnace roof vent leak with photos. | Roof vents, Roof problems, Leaking roof](https://i.pinimg.com/736x/33/98/f4/3398f4c54f899eef36f450a5236fdd8c.jpg)