By Mitch from Lake Stevens, WA on August 25, 2014
Is the b-type the same as ht? I have to replace sections through my roof. It is for an oil burning boiler that is 6' tall.
By eFireplaceStore on August 26, 2014
Answer:It is not. Type B venting is aluminum and galvanized steel construction and is only suitable for venting gas appliances. Oil burning appliances require the use of Class A chimney, with type HT being required by some models. If you are able to find any manufacturer information on the current piping, I will be happy to check availability of the proper replacement parts.
By Steve from Berlin, NH on August 30, 2017
Is type B the double-wall form with insulation in the middle?
By Brennan W. on August 31, 2017
Answer:It is not, Class B is made of aluminum. Insulated double wall pipe is Class A chimney.