Alert 440 (Flash Code 13) — Compressor Slowdown - High Heat-Sink Temperature

What does 440 mean?

The compressor speed is slowing down due to a high heat sink temperature. The inverter LEDs will flash code 13 (Red: One Flash, Green: Three Flashes). This is often a normal operation during high outdoor temperatures.

• Heat sink temperature is approaching its limit.
• Loose screws holding the inverter to the inverter board.
• Debris or obstructions impacting airflow across the heat sink.
• High outdoor temperatures.

Click steps to track your progress.

1. 1

   Wait five minutes for capacitors to discharge, then tighten the screws holding the heat sink to the inverter control board.

2. 2

   Check the heat sink for debris and ensure proper airflow.

3. 3

   Monitor heat sink temperature, compressor speed, and speed reduction status in the thermostat's diagnostics section.

4. 4

   If the alert occurs frequently at lower temperatures, check for obstructions or debris affecting airflow.