!!
critical ADT

Error Code Fire

A fire alarm is triggered; can be manually or sensor-initiated.

? What Causes This

Detected heat or smoke in the premises or user manual operation.

How to Fix It

Investigate and extinguish the source, then reset the system via touchpad as needed.

Source: page 23 of the official manual

From the manual

Manual page 23 — ADT error Fire

This error code appears in:

ADT Safewatch Pro 3000