Image forming apparatus featuring a temperature controlled fan

An image forming apparatus comprising:

• a first image bearing member;
• a first developing device for forming a toner image on said first image bearing member;
• a second image bearing member;
• a second developing device for forming a toner image on said second image bearing member;
• an intermediary transfer member capable of carrying a toner image transferred from said first image bearing member and a toner image transferred from said second image bearing member, and secondary transferring the toner image onto a recording material;
• a cleaning device for collecting toner remaining on said intermediary transfer member;
• heating means for heating at least the recording material;
• an executing portion capable of executing an operation in a first image forming mode for forming a toner image on said intermediary transfer member transferred from said first and second image bearing members and an operation in a second image forming mode for forming a toner image on said intermediary transfer member transferred from said second image bearing member without transfer of the toner image from said first image bearing member onto said intermediary transfer member;
• a temperature detecting portion disposed in said image forming apparatus;
• a fan for feeding air in said image forming apparatus;
• control means for controlling said fan on the basis of an output of said temperature detecting portion so that an air feed amount increases with an increase of a temperature indicated by the output;
• and
• a setting portion for setting a temperature so that a temperature at which the air feed amount is increased in the second image forming mode is lower than a temperature at which the air feed amount is increased in the first image forming mode.