Lockout 138 Flame too low

What the control is telling you

Flame signal is too weak for the control to keep the burner running.

Applies to: Trinity Tft60, Tft85, Tft110, Tft154, Tft201, Tft285, Tft340, Tft399

Likely causes

• Blocked venting or air inlet
• Fouled or faulty flame sensor
• Combustion settings off
• Electrical noise on site
• Failing limit switch in the ILK circuit

Test and repair steps

1. Check the exhaust, air inlet, blower, gas valve venturi and heat exchanger for blockage
2. Inspect the flame sensor for cracks or fouling; clean or replace
3. Recheck combustion readings and correct
4. Look for sources of electrical noise such as a large motor starting at the same time
5. Check the internal low water cutoff and any external limit between R and LIM

Models that show this code

13 models in Trinity Tft

Other codes on the same units

• Lockout 122 Light-off rate proving failed
• Lockout 122 Light off rate proving failed
• Lockout 123 Purge rate proving failed
• Lockout 123 Purge rate proving failed
• Lockout 143 Internal fault: Flame bias out of range 1
• Lockout 144 Internal fault: Flame bias out of range 2
• Lockout 145 Internal fault: Flame bias out of range 3
• Lockout 146 Internal fault: Flame bias out of range 4