HVACopedia

Lennox · Air conditioner

80003 Lost communication with wireless device

Medium severity

What the control is telling you

Thermostat lost contact with a wireless device. S30/S40 thermostat alert code 80003.

Applies to: Lennox communicating air conditioners incl. variable-capacity inverter units in S30/S40 smart thermostat systems

Likely causes

  • Device off, out of range or faulty

Test and repair steps

  1. Cycle device power.
  2. If not fixed remove from BLE network, factory reset, add back.
  3. Replace device if it persists.

Settings for these units

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Source: Lennox Residential Communicating Systems Alert Code Guide (V2) 100017 (3/2023), Table 2 Alert Codes and Troubleshooting, p.51. Summarized in our own words; check the original manual for your model.

Homeowner looking at this code? See what it means for you and when to call a technician.

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.