The limit is reset by pushing the red reset button on the limit. Operation of the limit control usually indicates a major problem with the heating elements or temperature control. Do not continue to push the reset multiple times. The problem causing the reset to function must be found and corrected to insure proper operation. The blanket of fiberglass insulation must be replaced over the surface thermostats and immersion heating elements before the power is turned on and the heater is returned to service.
CONTACTORS
FIG. 9 Magnetic Contactor
When the immersion thermostat and contactor option is provided, the power to the immersion electric heating elements is switched by a definite purpose magnetic contactor. The contactor is supplied with 120 VAC from the control circuit when the immersion thermostat senses a drop in stored water temperature below the desired set point. A magnetic coil in the contactor is energized to complete the electric circuit supplying power to the immersion heating elements. When the thermostat is satisfied, the contactor coil is
CONTROL CIRCUIT TRANSFORMER
FIG. 10 Control Circuit Transformer
When the immersion thermostat and contactor option is provided, a transformer is used to reduce the line voltage to 120 VAC for internal control operation. The transformer is fused on the primary side. The VA rating of the control circuit transformer is based on the load of the various components in the water heater control circuit.
IMMERSION THERMOSTAT(S)
FIG. 11 Immersion Thermostat
9
