Element Replacement Procedure
Warning: Before element replacement, make certain the boiler is drained below the element opening and lock out and disconnect the boiler’s main power to avoid the hazard of electrical shock, which could result in serious personal injury or death.
NOTE: To assist in breaking free the gasket, insert one of the flange bolts into the tapped hole provided.
NOTE: Since the elements often differ in length, check to assure that there is an adequate clearance (3/4” min.) between the end of the element and the opposite side vessel wall.
Check by measuring both the element extension (from flange to tip) and the distance from the tank flange face to the vessel wall.
You will feel the ferrule separate from the nut while tightening. A properly tightened ferrule nut will have separated from its ferrule and the ferrule will be squeezed or compressed onto the element sheath, thus providing a tight seal.
FIGURE 4-3. Element Installation Details
Source: Cleaver Brooks