Alarm Devices; Micro-Switch Introduce - Lennox MMA018SM4 Service Manual

4.3. Alarm Devices

Mini-Split indoor units can be connected to an alarm device such as a light or buzzer using two dry contacts on the
indoor unit main board.

4.4. Micro-Switch Introduce

Alarm Terminal Port
(CN33)
Connect the power; it must be less than 24V.
The current is less than 0.5A. If the unit encounters a problem, the relay closes and the alarm functions.
Figure 16. Alarm Device Connection Points (Typical)
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