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Parts for Whirlpool WED6200SW1 Dryer - AppliancePartsPros.com

See the attachment for the tech sheet.

I do not see a separate air flow sensor so my guess is that they monitor the inlet and exhaust thermistors and if the difference between them falls outside a spec an air flow error occurs.

Just to be 100% sure that it is not the vent system run the unit with the vent disconnected.
Unplug the unit and disconnect it from the vent system.
Now try a run.
If it now dries OK odds are the vent system needs checking/cleaning.
Be sure to check that the louvers on the outside of the house open correctly.

If you do not want any lint in the house.
Take a pair of pantyhose.
Put one leg into the other and then attach this to the dryer's vent.
Leave enough room so the pantyhose can balloon out like a windsock.

Both the above will let you check the temperature and the air flow.

Run the diagnostics to see if anything shows up.
Check that the blower wheel is clean.
Check your lint filter sometimes they can get coated with fabric softener residue and have to be cleaned with soap and water.

Does this give you any more info on the problem ??

Sort of helps but in a bad way re: makes it harder to find the actual fault.

I am thinking it could be one of the following:

1. The microprocessor or one of it's I/O chips are bad and are giving a false AF error.

2. There is a bad/intermittent/dirty connection to one of the thermistors. Could be a bad crimp at the plug etc.

3. Could be a bad (cold solder joint) on the control board, probably where the thermistors are connected. Bad solder joint are often a duller silver color and/or may have pin holes. it they look OK then gently wiggle the connector side while watching the leg in the solder side to see if it moves.
A magnifying glass comes in handy here.
May be elsewhere on the board but I do not know where to check as scematics are not available for the board.

Hello Denman,
While removing the control panel of my dryer I found the Tech Sheets for my series of dryer. I am going to scan them into my computer for safe keeping. Now would you like to have a copy of them for yourself to help the next person with there dryer. I hope they give me a clue as to what is giving me the AF error codes.