Having a problem with dryers not heating or not heating consistently?
"Sail Switch Open or Closed" errors?
If it isn't a mechanical problem, or dirty sensors
(click link to read that article: dryers-not-heating-clean-sensors.html),
(click link to read that article: dryers-not-heating-clean-sensors.html),
then take a look at the sail switch and damper.
What is the sail switch? It is a safety feature that turns off the heat source (or the dryer itself) if insufficient airflow is detected in the dryer vent.
In short the sail switch is usually a micro mechanical switch that is connected to a metal damper over a hole. When the damper closes the gas flame comes on and heats up the air and the dryer gets hot. If there isn't enough air then the dryer doesn't operate. The trick is the sail switch needs a vacuum to pull it closed over the hole. In order to create a vacuum you need good airflow.
If the edges of the hole, or the damper, are dirty then they don't make a tight seal and no vacuum is created. The damper doesn't close, thereby not clicking the sail switch to let the dryer control board know there is proper airflow and to ignite the gas.
The dampers should be checked and cleaned on a regular basis, MINIMUM when you pull off the front panels to clean your dryers. If you don't pull the front panels off regularly you'll have to clean them more often.
The sail switch and damper can be found on several different areas on different models of dryers. Some are inside the lint compartment, others on the back of the dryer in the open, some are on the back or side of the dryer under a panel. No matter where it is located on your dryer the principal is the same. In the example I'm using an older Maytag stack dryer.
This is the damper. Some models are round, some are square or rectangle shaped. This one is located inside the front panel, in the middle of the dryer, below the top pocket, next to the lint trap.
Notice the dirt on the edge of the damper.
If you move the damper back you see the dirt around the hole the damper closes over. This much dirt is plenty for the damper to not make a tight seal around the hole and therefore no vacuum is created.
This is the same damper as seen from the inside of the lint tray holder with the lint tray removed.
Notice all the dirt and dust around the edge of the hole and on the back of the damper. I removed some dirt so you can see the contrast.
Take a rag and wipe off the dust around the edge of the damper and the inside of the damper. You can use a damp cloth with water or whatever cleaner you prefer, however make sure the damper is COMEPLETELY DRY before starting the dryer, otherwise you will have dirt sticking to the clean areas and have to start all over again because you will have created the very problem you are trying to solve!
If you have a round damper you should be able to spin it so you can clean the whole edge.
Don't forget to clean the inside of the damper!
Clean the edge of the hole on both sides.
Clean the area all around the hole on the inside of the lint tray compartment.
This is the outside of the damper when it is clean.
This is the inside of the clean damper.
Inside edge of the hole. Notice the paint discoloration. That is normal.
Cleaning the damper and the areas on both sides of the hole should solve a lot of your "sail switch open" or "sail switch closed" errors.
Ev
A Heck of A Nice Guy
