Amana 4 Flashes

What does Amana 4 Flashes mean?

Four red flashes mean the primary or auxiliary limit circuit is open. The circulator blower runs continuously with no furnace operation. The limit opens to protect against overheating when there is insufficient conditioned air moving over the heat exchanger, so the control runs the blower to cool the unit while it waits for the limit to reset.

Symptoms

• Circulator blower runs continuously with no furnace operation
• Integrated control module diagnostic LED flashes four red flashes
• No heat is produced
• Furnace cycles on the high limit

Common causes

• Faulty primary or auxiliary limit switch
• Insufficient conditioned air over the heat exchanger from blocked filters or restrictive ductwork
• Improper circulator blower speed or a failed circulator blower
• Loose or improperly connected wiring

Diagnostic steps

1. 01

   Check the limit switches

   Check the primary and auxiliary limit switches and replace either with the proper replacement part if it is faulty.

2. 02

   Clear airflow restrictions

   Check filters and ductwork for blockage and clean the filters or remove any obstruction restricting airflow.

3. 03

   Verify blower speed and performance

   Check the circulator blower speed and performance, correcting the speed or replacing the blower if necessary.

4. 04

   Tighten the wiring

   Tighten or correct any loose or improperly connected wiring in the limit circuit.

5. 05

   Power off before servicing

   Turn power off prior to repair before replacing the limit switch or blower.

When to call a professional

Repeated high-limit trips can point to a serious airflow or heat exchanger problem that is unsafe to ignore. If clearing filters and confirming blower operation does not resolve the four-flash code, or if you cannot test the limit switches and blower speed, call a qualified servicer. Persistent overheating warrants professional inspection of the heat exchanger and ductwork.