A thermal control insert and a thermal resistant hollow block. The thermal resistant hollow block includes a hollow block having a cavity and an elongate member positioned within the cavity that has a generally spiral shaped pathway which forms a generally closed pathway to receive a heated fluid when the elongate member is positioned within the cavity of the hollow block. The generally spiral shaped pathway passes the heated fluid in a forward direction through the generally closed pathway toward a central open area at an inner end of the generally closed pathway of the elongate member. As fluid accumulates in the central open area, the fluid loses kinetic energy and becomes stagnant to provide a relatively high thermal resistance to heat transfer.