On January 7th, 2025, an Over-the-Air (OTA) firmware update was released for modulating and 2- stage communicating furnace controls. The update revises the primary processor on the modulating furnace controls from version 6 to version 7, and the secondary micro on all communicating furnace controls from version 3 to version 4. Testing has indicated that upon acceptance of the update at the Ion Black wall control, the update will be downloaded to the furnace control, starting the furnace control firmware update. The download and revision will occur with or without an active gas heat call present. During the download, the secondary microprocessor on the furnace control is updated and will reboot. If this reboot occurs during an active heating call, the gas valve relay will open, interrupting the heating call and generating a code 45.2 and/or a code 35.1. We have currently suspended this OTA firmware update as we work to eliminate the nuisance fault codes, and the email notifications being sent as a result. Furnace controls that may have already downloaded and installed the update need no further action or reversion of the firmware. Systems with wall controls indicating a firmware revision to be available may accept and update the furnace control with the understanding that if a heating call is active the heating call will be interrupted for up to 2 minutes until the control reboot is completed, and that a fault code 45.2 and/or a fault code 35.1 will be displayed. After the update the furnace control will stop displaying the fault codes, will automatically restart, and will commence the heating call if a demand is still present.

See attached Bulletin