A vertical seed conditioner may be formed of a plurality of sections that can be individually removed for repair and/or replacement without requiring the entire seed conditioner be permanently decommissioned. For example, the seed conditioner may be formed of a plurality of heat transfer sections stacked vertically with respect to each other to form the conditioning vessel. Each heat transfer section may include an inlet manifold, an outlet manifold, and multiple heat transfer tubes extending from the inlet manifold to the outlet manifold. The multiple heat transfer tubes may be spaced from each other to provide a gap between adjacent tubes through which the granular solid can travel.