5-277-04-066-001

A double-wall two-pass U-bend bundle gives 5-277-04-066-001 the thermal and mechanical margin expected of Diamondback tank heater equipment in in-tank heating with boiler water in the tubes and cross-contamination protection. The vented air gap between tube walls gives a visible telltale leak rather than allowing boiler water and tank contents to mix. Dimensionally it is a 4-inch shell unit in a 2-pass arrangement. It carries 3/4-inch O.D. tubes. As furnished, materials include cast iron bonnets, steel shell, and copper (double wall) tubes. Design ratings run to 150 PSI on the shell side, 150 PSI on the tube side, and 375°F maximum temperature. The series sees regular use in domestic water storage under double-wall codes, potable water storage tanks, and glycol-fed storage heating.