What is L- vent??

Tony_23

It is 1700 degree rated, insulated vent pipe.

Suitable for oil or NG and LP. Not wood or other solid fuels. Those require "all-fuel", AKA X-vent. 2100 degree rating.

JBW_2

L Vent

What is L-Vent? Double wall or single wall?
When is it used?

Home Depot Employee

Just to add

It is galv/galv dbl wall

versus SS/SS or SS/Galv

Most often seen on oil in the higher efficiencies

Jack_42

L-vent

L-vent is the min required pipe for venting oil fired equipment. While most of the chimney you get is the UL103HT listing, L-vent is UL103, with no hi temp rating. There are some interesting products for "problem solving" using L-vent. For instance, pellet vent is L-vent. It is made on B-vent dies with a ss liner in 3 & 4". I've used it as a chimney liner when nothing else would fit. It worked well there...when properly sized of course.

As well, one of its best uses is as a vent connector. Back when NFPA31 added appendix E (which remains an appendix although time has shown that the sizing is pretty spot on) I spoke with Rich Krajewski of Brookhaven, who along with John Strasser did the work on the appendix. Rich indicated that no matter what the configuration of the chimney the one thing that had the most positive influence on the operation of the flue was an insulated vent connector. Products that are L-vent rated are Selkirk's DS and Duravents DVL. These are available in 6 & 8 and 6,7,8 respectively. the pipe is best known as a close clearance connector for wood stoves. It has various lengths including telescoping, 90's 45's tees. Great stuff if you have a long vent connector or in fact as Rick said, it works well for any system. Adds a bit of cost but you get a 10 yr warranty on it too.

Bob Harper

Not sure of your references for L vent

L vent is listed to UL 641, which is rated at a max. temp. of 570F or 298.8C . Type 103 is "factory chimney" and is listed for 1,700F. Solid fuel, such as woodstoves requires 103HT or 2,100F chimney.

There is a difference in the codes as to how "venting" and "chimney" are applied.

DVL black close clearance pipe is ventilated pipe for solid fuel and is NOT L-vent. It carries a 6 or 9 inch clearance to combustibles while L vent carries a 3" clearance and factory chimney carries a 2" clearance in gen'l.

It is presumed that type 103HT chimney can pass the requirements for UL 441 for Cat.I gas and UL 641 for oil so the HT version is often referred to as "all fuel" chimney.

HTH,
Bob

Jack_42

Thanks for the listing corrections Bob

Sloppy on my part. The DS and pellet vent from Selkirk is L-vent rated. As L-vent it is an excellent vent connector for oil fired equipment, within its clearance requirements.