Hitachi Heating & Cooling - Page 8 - Recent Questions, Troubleshooting & Support

http://airconditioningfaultcodes.blogspot.com/2013/05/hitachi-error-codes.html I think this link should have the answers to your question. Hope this helps.

Two cause can create a frozen evaporator, a lack of gaz or a dirt filter, sometime a evaporator full of dirt. Check this two solution, if not ,you need a technitian to find the leak

clean the condenser coil (outdoor).

Slightly knock on the reversing valve, without breaking anything.

Look for the lines that run through the wall out to the outdoor unit. Turn off the power and then check the electrical connections at the outdoor unit. Inspect for broken wires. If no broken wires, remove the wires one wire at a time and then re-land the wire and tighten. Check for proper operation after performing this operation at both the indoor and outdoor unit.

Remove the batteries and place the unit in the warm sun for a few days. Make sure that you open the battery compartment. After that try putting the remote in a plastic bag with rice for a few days to get rig of all of the moisture. Retry with fresh batteries.

room sensor error , replace sensor by new one