Admiral Tumble Dryer Error Code F28: Moisture Sensor... | appliancefaults.com

Technical Background:

The MCU (Main Control Unit) sends a low voltage signal to the moisture sensor bars. As clothes tumble, the moisture content affects the resistance between the bars. The MCU reads this resistance to determine dryness and adjust the cycle. A break in the voltage path or an illogical resistance reading triggers the F28 fault.

Symptoms:

The homeowner observes that the dryer stops prematurely, clothes are either still damp or excessively dry, and the F28 error code is displayed on the control panel.

Possible Causes:

Faulty moisture sensor.
Wiring harness issue between sensor and control board.
Defective control board (MCU).
Loose or corroded connections at the sensor or control board.
Lint buildup affecting sensor readings.

Solution:

1

Unplug the dryer from the 120V AC outlet and disconnect the dryer vent.
2

Locate the moisture sensor bars inside the dryer drum. Typically, these are metal strips near the lint filter.
3

Using a 1/4-inch nut driver, remove the screws securing the sensor bars.
4

Inspect the wiring and connections to the sensor. Look for any signs of damage, corrosion, or loose connections.
5

Use a multimeter to check the resistance of the moisture sensor. Refer to the dryer's service manual for the correct resistance range. An open or shorted sensor indicates a fault.
6

If the sensor is faulty, replace it with a new one. If the wiring or connections are damaged, repair or replace them.
7

If the sensor and wiring are good, the control board (MCU) may be faulty and require replacement. This often requires licensed technician assistance.

Safety Warning:

Always disconnect power to the dryer at the breaker panel before performing any repairs. Some components may store a residual electrical charge, even after power is disconnected. Capacitors can hold dangerous voltage.

Prevention:

Clean the lint filter after every load. Periodically vacuum the inside of the dryer drum and the moisture sensor bars to remove lint buildup.

Expert Tip:

Some Admiral dryers have a diagnostic mode. To enter, press and hold the Start/Pause and Cycle Select buttons simultaneously for 3 seconds. This may allow you to clear the error code after repair or access sensor readings.

Frequently Asked Questions

•What is the correct resistance reading for the moisture sensor on my Admiral dryer model?

Refer to the service manual or technical sheet for your specific model. Resistance values can vary, but typically fall between 10k and 100k ohms when dry.

•How do I test the wiring harness between the moisture sensor and the control board?

Use a multimeter set to continuity mode. Disconnect the harness from both the sensor and the control board. Check for continuity between the corresponding wires. Also, check for shorts to ground by measuring resistance between each wire and the dryer chassis. It should be a very high resistance (megaohms).

•Where can I find a replacement moisture sensor for my Admiral dryer?

You can find replacement sensors at appliance parts retailers, online retailers like Amazon or RepairClinic, or from a local appliance repair shop. Make sure to have your dryer's model number handy to ensure you get the correct part.

Admiral Tumble Dryer Error Code F28: Moisture Sensor Fault Repair Guide

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•What is the correct resistance reading for the moisture sensor on my Admiral dryer model?

•How do I test the wiring harness between the moisture sensor and the control board?

•Where can I find a replacement moisture sensor for my Admiral dryer?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: