Wolf M Series Code 4421: Upper cooling fan not detected

What 4421 means

On Wolf M Series wall ovens such as the SO3050TM/S/T or DO3050PM/S/P, code 4421 means the control cannot detect the upper cavity cooling fan running. The companion code 4422 reports the same condition for the lower cavity. You see the number on the display, the oven may stop heating or refuse to start, and the fan may be silent or running without being sensed.

Common causes of 4421

Upper cooling fan not turning or blocked by debris
Fan feedback signal not reaching the control
Fan wiring connection or fan motor failing
Relay board not powering the fan

✓ One safe check you can try

1. Turn the oven off and let it cool for 30 minutes. 2. Check that nothing blocks the vents around the oven and that cabinet air gaps are clear. 3. Switch the oven's circuit breaker off for one minute, then on. 4. Start a short bake and listen for the fan. If 4421 returns, stop using the oven and call us.

! Why to stop there

The fan and its feedback signal sit behind the oven panels, and opening them near live power is not safe for owners.
Guessing at a replacement fan can waste money if the real cause is wiring or the relay board.
We measure the fan and its signal before quoting, and we give you the price in writing before any work.
Our repair carries a 30-day workmanship warranty.

Opening a panel yourself does not automatically cancel a manufacturer warranty, but it can cause accidental damage, and some manufacturers set their own service conditions. Check your warranty terms, or ask us, before deciding.

→Same appliance

Other Wall Oven codes

0121Wolf M Series Oven Code 0121: upper right convection relay shorted 0221Wolf M Series Code 0221: Upper Bake Element DLB Shorted 0321Wolf M Series Oven Code 0321: Broil Relay Shorted on the Upper Element 0421Wolf M Series Code 0421: upper left convection relay shorted 0630Wolf M Series Oven Code 0630: Auxiliary DLB Shorted 1C21Wolf M Series Code 1C21: Both upper bake element DLbs open 3621Wolf M Series Code 3621: Upper door locked, not in clean 1D21Wolf M Series Code 1D21: Both upper broil element DLbs open

44214421 questions

Is 4421 about the upper or lower oven?

The upper cavity. Code 4422 is the same message for the lower cavity, so on a double oven the last digit tells you which one needs attention.

Can I keep baking with this code showing?

We advise against it. Without a confirmed cooling fan the oven can run hot inside its cabinet area, and the control may shut heating down anyway, so it is safest to wait for a visit.

Will a breaker reset clear it?

Sometimes a reset clears a one-time glitch. If the code comes back after a short bake, the fan or its signal needs a technician to test it.