What Does Monogram Microwave Error Code F8 Mean?

Error code F8 on a Monogram microwave indicates a relay drive circuit failure on the main control board. The relay that controls power to the magnetron or other high-voltage components has developed a fault — either failing open (no power to component) or welded shut (component runs continuously).

Common Causes

  • Welded relay contacts – High-current switching has caused relay contacts to fuse together, causing the magnetron to run when it shouldn’t. This is a safety hazard.
  • Failed relay driver – The transistor or circuit driving the relay has failed, preventing the relay from activating.
  • Control board failure – The broader control board has failed.

How to Troubleshoot

  1. Stop using the microwave immediately – A welded relay can cause the magnetron to run with the door open, which is dangerous. Unplug the unit.
  2. Do not reset and continue – F8 is a safety-critical fault that must be diagnosed before use.

When to Call a Professional

F8 requires control board inspection and possible replacement. Call 844-752-7887 immediately for urgent Monogram microwave service.

Need Help? If the error code hasn't resolved after basic troubleshooting, call our certified Monogram technicians at 844-752-7887 for professional diagnosis and same-day repair.