Heat Controller B-MMH09FA-1 manual Description Cause of error Check point & Normal condition

			Troubleshooting Guide
Error	Description	Cause of error	Check point & Normal condition
code
			• Power input AC 230V.(Outdoor, Indoor)
			• The connector for transmission is disconnected.
05 / 53	Communication		• The connecting wires are misconnected.
	(Indoor ➔ Outdoor)	• Poor Communication	• The GND 1,2 is not connected at main GND.
			• The communication line is shorted at GND.
			• Transmission circuit of outdoor PCB is abnormal.
			• Transmission circuit of indoor PCB is abnormal.

❑Check Point

1.Check the input power AC 230V.(Outdoor, Indoor)

2.Check that the communication wires are correctly connected.

➔Adjust the connection of wire

➔Confirm the "Live", "Neutral“ wires.

3.Check the resistance between communication line and GND.(Normal : Over 2MΩ)

4.Check the connector for communication is correctly connected.

5.Check the connection of GND1, GND2, and main GND.

6.If one indoor unit is operating normally, outdoor PCB has no problem.

➔Check the other indoor unit.

* CH05 is displayed at indoor unit, CH53 is displayed at outdoor unit.

- 73 - Service Manual