Venting oil burning appliances

[Anthony]

Can oil burning appliances be vented with a class b vent or does it have to be class L?

[Jerry Peck - Codeman]

From the 2006 IRC:
- Table M1804.1
- - Type L oil vents are for oil-burning appliances which are listed and labeled for venting with Type L vents

G2403 General Definitions
- VENT. A pipe or other conduit composed of factory-made components, containing a passageway for conveying combustion products and air to the atmosphere, listed and labeled for use with a specific type or class of appliance.
- - Special gas vent. A vent listed and labeled for use with listed Category II, III and IV gas appliances.
- - Type B vent. A vent listed and labeled for use with appliances with draft hoods and other Category I appliances that are listed for use with Type B vents.
- - Type BW vent. A vent listed and labeled for use with wall furnaces.
- - Type L vent. A vent listed and labeled for use with appliances that are listed for use with Type L or Type B vents.

The last part is the answer to your question: An appliance listed for use with a Type B vent may be vented into a Type L vent, however, the reverse does not hold true. Thus an oil-burning appliance listed and labeled for venting into a Type L vent is not suitable for venting into a Type B vent.

The Type L vent is listed for higher temperatures than a Type B vent. Also, the clearances around a Type L vent are greater than around a Type B vent, therefore a Type B vent could create a fire hazard if an appliance is listed for use with a Type L vent, even if the Type B vent itself did not fail, combustible material around the Type B vent could catch fire due to the higher temperatures and lack of sufficient clearance.

If you need more information I can contact my expert and have him reply with more information.