Why Your Furnace Vent Pipe Can Leak Years Later Even When the Joint Looks Finished - Part 2

In this episode of HVAC Know It All, host Gary McCreadie talks with Gaetano Altomare, Category Manager - Plumbing at IPEX by Aliaxis, about installing nonmetallic flue gas venting correctly. They cover pipe preparation, solvent welding, inspection, primer requirements, and combustion testing. Listeners will learn how to avoid weak connections and preserve vent integrity during installation and service.

Gaetano brings firsthand knowledge of certified venting products, manufacturer installation guidelines, and the development of dedicated combustion-testing fittings. His manufacturer's perspective connects the mechanics of pipe-and-fitting fusion with practical field decisions, including cutting older pipe, verifying compatible components, and sealing test-access plugs.

Key Takeaways How square cuts, beveled ends, clean pipe surfaces, and a dry-fit interference check help produce a properly fused vent connection.

Why certified vent systems require components from one manufacturer and how optical brighteners help inspectors verify primer and solvent cement use.

How local requirements, installation temperatures of 32°F and colder, and pipe sizes of six inches and larger determine primer use for the products discussed.

How a dedicated combustion-testing fitting installed within two feet of the appliance provides probe access without drilling the vent pipe.

Why the test-access plug discussed requires two full turns of Teflon tape rather than relying on plastic threads alone to seal.

Key Timestamps  00:00 – Factory Direct Filters Ad

00:42 – Episode Introduction

03:14 – Cost difference between PVC and CPVC

08:18 – Glue or chemical bonding

11:21 – Primer requirements for temperature and local jurisdiction