Dexter Laundromat Dryer Error Code F1: Temperature Sensor Short

What does Dexter error code F1 mean?

A Dexter coin dryer with the T-30, T-50, T-80 or T-120 control uses a temperature probe under the drum basket to keep the heat where it should be. The control reads the probe on every cycle. If the probe circuit shorts, the control sees a reading that does not exist in a real dryer and will not start, since it cannot control the heat. The display shows F1 and holds it until the programming button is pressed, even after the cause is gone. In a laundromat the attendant sees F1 because customers put in coins and the dryer does nothing. The manual lists a shorted probe under the basket, a pinched wire or damaged connector, lint or moisture bridging the probe pins, and a control input that reads the probe as shorted. Lint and damp air are common in laundry rooms, which is why a cleaned lint screen is the first step, and why a tagged out dryer is better than an unreliable one.

Affected models and control systems

This page covers Dexter coin dryers with the T-30, T-50, T-80 and T-120 control. Other Dexter washers use their own codes, including a different F1.

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

• F1 shows on the display and the dryer will not start
• Customers pay and nothing happens
• F1 stays on until the programming button is pressed

Possible causes

Listed in Dexter's documentation

• A shorted temperature probe under the drum basket
• A pinched wire or damaged connector at the probe
• Lint or moisture bridging the probe pins
• A control input that reads the probe as shorted out

Other likely causes — what usually sits behind error code F1 on this control. A technician confirms which one it is before any part is replaced.

• A probe wire flattened against the basket support when the drum was serviced
• Wet lint that has packed into the probe connector in a damp laundry room
• A probe that has been shorted by sugar from a spill that reached the connector

Safe checks before calling for service

How a technician diagnoses error code F1

1. Read the code and clear it with the programming button to see if it returns.
2. Inspect the probe, the wire and the connector under the basket.
3. Measure the probe resistance and compare it with the chart.
4. Check the control input with a known resistor.
5. Replace the probe, harness or control only after the readings show which one has failed.

How error code F1 differs from similar codes

The Dexter washer also shows an F1, for a door lock error. The dryer F1 is a temperature sensor short.

Technical reference

Document

Dexter Common Dryer Troubleshooting and Error Codes (Dryer Error Codes, p. 6)

Maker documentation

Dexter owner support

Models / control

Dexter T-30, T-50, T-80 and T-120 coin dryer control

Section

Dryer Error Codes table (Symptom / Probable Cause / Suggested Remedy), p. 6

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.