American Dryer Error Code EXHAUST HIGH TEMP FAULT: Basket Overheat

What does American Dryer (ADC) EXHAUST HIGH TEMP FAULT mean?

The Phase 7 OPL control reads basket temperature through an exhaust temperature probe. Unlike a disk, which simply opens at a set heat, the probe gives the control an actual number to compare against a limit. If that reading goes above 220 F, the control considers the dryer unsafe, turns it off and shows EXHAUST HIGH TEMP FAULT. Operators see the dryer stopped partway through a cycle with the message on the display. The maker says lint and a restricted exhaust are the usual place to look first, because heat that cannot leave through the duct builds up in the basket. The manual's list also includes a probe that reads low, which can let the burner run too long before the control sees the temperature rise, a burner or heat control that keeps firing, and too little air moving through the basket. The message therefore points at three areas at once: airflow, the probe, and the heat control. Which of them is responsible is something to settle with measurements, not by guessing at a reset.

Affected models and control systems

This applies to gas American Dryer tumblers with the Phase 7 OPL microprocessor controller, such as the AD-115, AD-120 and AD-170, and the Phase 6 control on ML-175 and ML-190 models. Other controller generations use different codes.

Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.

What you may notice

• The dryer stops mid-cycle with EXHAUST HIGH TEMP FAULT displayed
• The basket and door glass feel unusually hot
• Loads were taking longer to dry in the days before

Possible causes

Listed in American Dryer (ADC)'s documentation

• A lint screen and exhaust duct packed with lint
• An exhaust temperature probe that reads low
• A burner or heat control that keeps firing
• Too little air moving through the basket

Other likely causes — what usually sits behind EXHAUST HIGH TEMP FAULT on this control. A technician confirms which one it is before any part is replaced.

• A probe that has drifted and reads cooler than the real basket, so the control keeps heat on past the limit
• A heat control relay that sticks closed and keeps the burner calling after the setpoint
• Lint packed in the duct elbow nearest the dryer, throttling airflow while the screen looks clean

Safe checks before calling for service

How a technician diagnoses EXHAUST HIGH TEMP FAULT

1. Read the message and compare the probe reading with a separate thermometer in the exhaust.
2. Measure the probe resistance cold and at temperature.
3. Check airflow and static pressure in the duct and look for lint buildup.
4. Verify the heat control stops the burner at the setpoint and does not stay on.
5. Check the burner input and gas pressure against the data plate.
6. Correct the cause and run a full loaded cycle.

How EXHAUST HIGH TEMP FAULT differs from similar codes

EXHAUST HIGH LIMIT FAULT on this control reports a disk that has opened, while this message reports a measured basket temperature over 220 F.

Technical reference

Document

AD-115/120/170 ML-120/130/145/170 Service Manual, Phase 7 Microprocessor Controls (part 451102 R2), Diagnostic messages pp.43-44

Maker documentation

American Dryer (ADC) owner support

Edition

Part 451102 R2

Models / control

Phase 7 OPL microprocessor controller (also Phase 6 on ML-175/190)

Section

Diagnostic messages pp.43-44

Checked

October 2026

We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.