Why do AMPCO® systems require expansion joints?
Without expansion joints, the expansion characteristics of a VSI system inner wall are similar to a solid rigid tube. The inner wall is also the primary connection and load bearing member of the system. Therefore, to absorb expansion induced by flue gas temperatures, an expansion joint or bellows joint must usually be installed between any two fixed points. A fixed point is any VSI Support Assembly or the appliance. Expansion joints (EJ) are recommended for boilers, while bellows joints (BJ) are required for generators. The approximate expansion of the inner wall is one inch per 100º F per l00 feet. Consult the installation instructions for details.
