What is F1 and why does it stop constantly when filling

Fill solenoid if water constantly filling when power switched off. Level sensor in sump if just overfilling but stops when power off

There should be F1 on both displays. "If power fails to the bottom tub it will cause the top tub to go F1. Test heater plate." (from the service manual).
If there is F1 on both displays it could be a faulty flood switch or PCB.

check the drain hose. Is it in the drain below the fill line of the washer?
In other words -- the drain line should be above the level of the washer lid top and in the line about 4-6 inches

The F1 error code means that the computer thinks a button on the touchpad is stuck. Sometimes this can be resolved by making sure the touchpad connector fits tight into the control board. The F1 code can be cleared by pushing CANCEL/OFF. If it returns the touchpad needs to be replaced

Under top the hose from pressure switch < water level switch> goes to air dome . Check hose for small pin hole or pinch.

The manufacturer has issued a remedy for the F-1. What you do is empty the machine of water and unplug it. Open the control panel and remove the pressure hose. Blow out the hose to remove sediment . Re secure it to the control and retry. No parts needed. F-1 Error info

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I have the f51 code filled up with water and stopped. They are coming today to fix it. Called whirlpool and they are fixing this at their expense. I have the extended warrenty they said they are fixing codes f1 and f51

F1-->Failed Thermistor Control Replace ERC
you will have to replace the ERC or Electronic Range Control or the touch pad.

a F1 code means you have a bad control board.

Tul2pi, there are several things that could cause this. 1. shorted keypad. If you unplug the keypad ribbon from the board and the beeping stops it's more than likley your problem. 2. Temperature probe in the oven may have gone bad. You would have to ohm this out. At 75 degrees it should read approx. 1091 ohms. 3. Worst of all it would be a control problem itself where as you would have to replace the control board. Since you are so close to the warranty period, I would call Frigidaire at 1800-944-9044 and see if they would cover it...Catriver..post back.