(1) Heater Inspection

The heater consist of heater terminals (-A1) and (-A2). They
  comprise one heater while heater terminals (-B1) and (-B2)
  also comprise a heater. Use the tester to inspect for possible
  broken wires or any short-circuits.
The heater's measured resistance value is between 3Ω~15Ω
  depending on volume, and the short circuit measure between
  the case and heater terminal must be greater than 1MΩ.
Sensor tube (-C) is the over-heating control sensor.

(2) Heater Replacement

Turn off the power and discharge until the steam pressure
  reaches zero.
Completely discharge all water inside the steam generation
  tank.
Disassemble the wires connected to the heater terminal after
  marking them.
Unscrew all the bolts (-D) on the heater plate.
Remove the shorted or problematic heater.
If there is damage to the heater plate packing (-F), remove
  and replace with a new one. <The packing should be done
  with 3mm thick, high temperature-grade red spider.>
Scrape off any scale build-up inside, and remove any scale
  on the surface of the heater.
Re-fasten the heater plate, reconnect all wires, and turn the
  heater on.