Product not toasting adequately (too dark or too light)

Adjust the Light/Dark Settings.
Perform a Factory Reset.
The front and/or rear curtain is damaged/missing.
Settings require reprogramming.
See the document HRT-5H New Muffin Settings Programming for more information.
Perform the steps in Preventative Maintenance Card PR66.
If the steps above do not resolve the issue, call for service.