TOPIC: B vent

When is B vent needed? Is it only for propane and natural gas? What about woodburning appliances? This is a weak area for me.

I believe on propane and natural gas. It is needed from the point it runs through the ceiling/firewall until it vents out the roof. It can be single wall until that point. I believe it also has to have a 1" gap from any flammable material.

Don't quote me on this because I cant find any documentation, but I don't think you can use B vents on wood burning fireplace.  I know you can use metal flues but I think they have another rating for them.  I'm trying to find something to say what can be used with what.

I don't think this quite answers your question but it might be of interest for some.

us.exhausto.com/library/3911002.pdf

NACHI's HVAC training program is very good and covers a lot of this. I don't remember if it covers wood burning vents, but very good information on furnaces, boilers and such.

Here is a good link Mike.

It explains various ways of venting fireplaces.

www.acehardwareandhearth.com/fireplace-venting-installation.asp