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Display shows two horizontal bars (soft disable) - Lennox SL297NV
What is going on
Two horizontal bars on the 7-segment display mean the iComfort thermostat found a device on the RSBus it does not recognize and put it in soft disable until it is configured.
Likely causes
- Miswired RSBus between thermostat, damper control, indoor and outdoor units
- Device not set up in the thermostat
Check in this order
- Confirm wiring between all devices (thermostat, damper control module, indoor and outdoor units).
- Cycle power to the control that shows the bars.
- Run the room thermostat through setup.
- In the thermostat go to setup / system devices / thermostat / edit and press reset.
- If needed repeat and press resetAll.
Applies to: SL297UHNV in iComfort communicating systems
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Source: Lennox SL297UHNV Installation Instructions 507760-02 (02/2018), Integrated Control Diagnostic Modes, Soft Disable, p.54. Written in our own words; check the manual for your exact model.
For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.