Tempstar 8 Flashes

What does Tempstar 8 Flashes mean?

On a Tempstar packaged gas/electric unit, the integrated gas unit controller (IGC) LED flashing eight times indicates an internal control fault. Table 5 of the installation manual lists eight flashes as this status code, meaning the IGC has detected a fault within the control itself rather than in an external switch or the gas train.

Symptoms

• IGC LED flashes eight times instead of staying continuously on
• Erratic or interrupted heating operation
• Unit may not respond normally to the call for heat
• Fault reported by the control board's own diagnostics

Common causes

• Internal fault detected by the IGC control board
• Control board hardware problem
• Electrical disturbance affecting the control
• Marginal low-voltage supply to the control

Diagnostic steps

1. 01

   Confirm the LED code

   Remove the control access panel and verify the IGC LED is flashing eight times, identified in Table 5 as an internal control fault.

2. 02

   Check the low-voltage supply

   Verify the control is receiving proper low-voltage power, since the table also ties no-power and hardware conditions to the control board.

3. 03

   Cycle power to the control

   Remove and restore power to the unit and observe whether the IGC returns to a continuously on LED or repeats the eight-flash code.

4. 04

   Note recurrence for the technician

   Record whether the fault clears or returns so a technician can determine if the control board needs replacement.

When to call a professional

Call a qualified service technician if eight flashes recur after power has been cycled. An internal control fault typically requires evaluating or replacing the IGC board, which the manual reserves for a qualified technician with proper tools and test instruments. Avoid swapping control components without confirming the fault, and do not jumper any safety device while diagnosing.