What does 89-02 mean?

A warning that the heat exchanger might be freezing up while the unit is operating in heating mode or producing domestic hot water.

• Air filter is dirty
• Outdoor unit fan is not working properly
• Low ambient temperature

Click steps to track your progress.

1. 1

   Clean or replace the air filter.

2. 2

   Check if the outdoor unit fan is spinning freely.

3. 3

   Ensure the unit is not operating at temperatures below its specified range.

4. 4

   Monitor the system; if it persists, call for service.