Error Code 1 Flash
High

Coleman DGAA056BDTA Error Code 1 Flash: Ignition Failure

TL;DR
Your Coleman DGAA056BDTA failed to ignite after three attempts and has locked out for one hour. a common DIY first step is cleaning the flame sensor with a Scotch-Brite pad.
Disclaimer
This article is for informational purposes only and does not guarantee the accuracy or completeness of the information provided. Always turn off power and gas supply before attempting any repairs. If you smell gas, leave immediately and call your gas company. Consult a licensed HVAC technician for diagnosis and repair. Any actions taken based on this information are at your own risk.

What Does Code 1 Flash Mean?

Code 1 (1 Flash) on the Coleman DGAA056BDTA indicates an ignition failure. The ignition control provides a 30-second warm-up period for the hot surface igniter. The gas valve then opens for 10 seconds. If the flame is not detected within 2 seconds of the gas valve opening, the gas valve shuts off and a retry operation begins. If three retries occur during a single call for heat, the furnace shuts down for one hour before trying again.

This code can appear for several reasons. The most common causes are no gas supply reaching the burners and a faulty or misaligned hot surface igniter. A dirty or oxidized flame sensor is also a frequent culprit — the sensor may not detect the flame even when it is present, causing the control board to shut off gas as a safety measure. A malfunctioning gas valve that does not open properly can also prevent ignition.

Of these causes, cleaning the flame sensor is the most accessible DIY repair. The other causes typically require professional diagnosis and repair.

Common Causes

Cause Likelihood DIY?
No gas supply to burners Most common ✗ Call a pro →
Faulty or misaligned hot surface igniter Most common ✗ Call a pro →
Dirty or oxidized flame sensor Common ✗ Call a pro →
Gas valve malfunction Common ✗ Call a pro →

When to Call a Professional

Contact a licensed HVAC technician if:

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Sources

  1. Coleman DGAA and DGAH User's Information, Maintenance and Service Manual

✓ Verified against manufacturer service manual — March 2026