An error code appears on the display of the FR-850

When using the FR-850, if the [HOT AIR] button lights up red and an alphabetical error appears on the screen, please check the following.

Disconnect the power plug from the outlet, and start checking and taking action.
Please contact the store of purchase or Hakko's official distributor if the error does not disappear after you take the necessary action.

Display	Point to be checked / How to handle
	Is the nozzle inserted into the handpiece properly until it stops at the end? Is the nozzle inserted into the handpiece properly until it stops at the end? Insert the nozzle firmly until it stops at the end. Is the heating element/sensor disconnected? Is the heating element/sensor disconnected? Measure the resistance between the heating element and sensor, and if the measured value is abnormal, replace the nozzle. 【Measurement point/Normal resistance value】 NA01： 6.2Ω±10%（at room temperature）
	Are there any strong noise sources in the working area of the unit? Are there any strong noise sources in the working area of the unit? Use the unit away from the possible noise source.

 Please contact the store of purchase or Hakko's official distributor if you cannot solve the problem by trying the above.