What do the CH error codes mean on the remote controller display?

The CH error codes indicate specific system problems detected by the unit's self-diagnosis function. CH 01 means indoor room temperature thermistor error, CH 02 means indoor piping thermistor error, CH 03 means indoor main body/remote controller unit communication error, and CH 04 (Optional) means water level float switch error. When CH flashes on the wired remote controller display, you should contact your serviceman or dealer. (Page 20)