The wall pass through is for 5" pipe and walls 4 1/4" to 8 1/2" thick (extensions are available for thicker walls). A storm collar is recommended to seal around it and the vent pipe. The stainless steel heater vent pipe and fittings feature patented built-in mechanical locking band and triple-lipped directional gaskets. All pipes and components are engineered with smooth clean welds located 90° from mechanical locking bands. All pipe and fittings are UL1738 approved for category II, III and IV venting applications.
What is UL 1738? In short, it is a US standard for gas venting systems required in category 3 applications. Category 3 refers to positive vent pressure which is created by exhaust blowers in unit heaters. These vent systems must be constructed of AL29-4C® stainless steel, contain gaskets for sealing, and have a built in mechanical locking band among other requirements. All category 3 vent pipe and fittings offered are single wall.
- Built-in adjustable 18" vent pipe
- Made of AL29-4C® super-ferritic stainless steel
- Built-in high temp silcone gaskets for air tight seal
- Built-in locking band to insure a secure fit (no hardware needed)
- UL1738 approved for category 3 venting applications
- Limited lifetime warranty