Low Temperature Resistant Protection
“LO” Designates the room freeze protection that is designed into the control board. This feature will automatically turn on the heat if the indoor sensor reads a temperature below 7 degrees C so that indoor piping does not freeze (even if the unit is off). During the “LO” operation there will be no control of the unit until the indoor space reaches approximately 10 Degrees C.
Possible Triggers
Leaks around the sleeve allow cold outdoor air to leak into the room causing a different reading
- Window open near the unit ( many people do this in bedrooms at night)
- Indoor and outdoor thermistors are connected incorrectly or damaged
Faulty board logic in the control board has been corrupted.
Corrective measures
- Ensure no leakage sleeve to wall and unit to sleeve if the seals or calking is damaged or missing replace them so there is no penetration of cold outdoor air
- Check thermistors for correct connection to the board and insure no damage to the insulation
If all others check out replace the board.
How long would it take to resolve the issue on its own?
Once the indoor ambient temperature reaches above 13℃ (55℉), the low temperature resistant protection will be stopped. This means the 'Lo' will disappear and the indoor temperature will be displayed.
How to Disable this feature? (Not Recommended)
We do not recommend disabling this feature,. This is a built-in safety feature and possibly cause your pipes to freeze and damage when turning on the heat. However, if needed, there are two ways to display, disabling dip switch #5 or unplugging the unit