Here are the equivalent settings for the Model B and C ergometers. All are approximations, and I do not vouch for the accuracy.

     Model B                    Model C
Big Gear Fan Closed (easiest)   3 - 3.5
Big Gear Fan 1/2 Open           5 +/-
Big Gear Fan Open               6 - 7
Small Gear Fan Closed           8 - 9
Small Gear Fan 1/2 Open         10 +/-
Small Gear Fan Open             Not available on Model C