Primary Heater Does Not Heat

  • Turn on heat zones.
  • Check CB1 for A-side heater and CB2 for B-side heater
  • While red temperature controller light is on, measure voltage (5 VDC) between T3 and T4 on SSR.
  • While red temperature controller light is on, measure line voltage (230 V) between T2 of the heater control relay and T2 of the SSR.
  • If testing fails to determine the problem, replace the SSR.
  • The two primary heater controllers are interchangeable.
  • To test for a faulty controller, turn off the main power disconnect and disconnect incoming power.
  • Replace the suspect controller and retest.
  • If this occurs, replace the thermocouple. See Replace Thermocouple, in manual.
  • Check for a resistance of 4-6 ohms between purple and red wires on the temperature controller.
  • There should be a reading of infinity between the ground wire and purple wire.
  • Thermocouple must make contact with the heater cartridge.
  • Heater cartridge must be functioning properly.
  • Lack of either of these conditions may cause erratic temperature control and possible overheating. To check thermocouple position, see Replace Thermocouple, in manual.
  • See Replace Primary Heater, in manual.