Chimney Pipe Buying Guide
This guide aims to aid in understanding the various types of piping systems for different appliances. The term Chimney Pipe refers to wood-burning appliances and includes Class A chimney pipe and Stovepipe. Venting pipe, on the other hand, is for gas appliances and comprises Direct Vent Pipe, Type B Gas Vent pipe, and Pellet Vent pipe. To ensure compliance with local building codes, it is crucial to read the instruction manual before installation and establish venting requirements for the appliance.
Class A Chimney Pipe is specifically designed for wood-burning fireplaces and stoves, or for transitioning stove pipe through a wall or ceiling. It is commonly known as double-wall, triple-wall, all-fuel, or insulated chimney pipe. This type of chimney pipe is made up of either double-wall or triple-wall pipe, although triple-wall pipe is becoming less common. The inner pipe is responsible for encasing heat emitted from fireplaces and carrying combustion particles outside, while the space between the inner and outer walls acts as an air jacket, insulating the chimney pipe and preventing the outer wall from overheating. It is crucial to use only one brand of Class A Chimney Pipe throughout the entire chimney system, as each brand is engineered specifically to work together. If a brand is discontinued or obsolete, starting from scratch is necessary. When selecting between galvanized steel (galvalume) or stainless steel, galvanized steel is recommended for use in areas where it is not exposed, such as in the masonry, chase, attic, or an indoor enclosure, due to its lower cost. However, if the pipe will be exposed, it is best to use stainless steel to prevent rust and corrosion from the elements. If galvanized steel is used outside, it is important to paint it with high-temperature, rust-resistant paint. Some examples of Class A Chimney pipes are Ventis Class A, DuraVent's DuraTech and Selkirk Ultratemp.
Direct vent piping is specifically designed for gas or propane stoves and fireplaces that require direct venting. This type of venting is highly favored due to its efficient and easy installation process. Direct-vent utilizes outside air for combustion and exhausts all by-products outside through either co-axial or co-linear piping. Co-axial piping is a system where a smaller inner pipe is fixed inside a larger outer pipe separated by spacers. The inner pipe removes combustion by-products and vents the exhaust outside while the outer pipe brings fresh air from outside for combustion. Co-linear piping, on the other hand, uses two separate pipes for intake and exhaust. This type of piping is only used if an old chimney is being utilized and has been tested by the fireplace manufacturer. Some examples of direct vent piping are Proform Direct Vent Pipe and DuraVent's DirectVent Pro.
Stove Pipe is specifically designed for venting wood-burning stoves and must be confined to the room where the stove is installed. When the pipe reaches a wall or ceiling, it must be replaced with Class A pipe because Stove Pipe doesn't possess adequate clearance to combustibles for passing through walls or ceilings. If converting through the ceiling, a ceiling support box or round ceiling support piece is necessary. If converting through a wall, a thimble is required. Stove Pipe is also recognized as black pipe and single wall pipe. Some prime examples of Stove Pipes are Ventis Black Stove Pipe, DuraVent's DVL and DuraBlack.
Type B Gas vent is typically utilized in older homes and is not as widespread in hearth venting today. It is a metal pipe with double walls that is employed for venting appliances that have draft hoods. Compared to direct vent and vent-free units, Type B is less effective because it must end through the roof, potentially blowing cold air into the house if a downdraft occurs. Type B is also known as b-vent or natural vent. An example of Type B Gas Vent Pipe is DuraVent’s Type B Gas Vent.
Pellet vent pipes are designed for use with stoves that burn pellets or corn. They have a small diameter ranging from 3-4 inches and only require a 1-inch clearance to combustibles. Pellet vents are capable of passing through walls and ceilings, making them suitable for use from start to finish. They can also be terminated either horizontally or vertically. Some examples of a pellet vent pipes are BioVent, DuraVent's Pellet Vent Pro.