Hi-this is Sue from GE. Thanks for your interest! The blower will need to be rotated for indoor (recirculating) venting. The directions are provided in the installation instructions included with the microwave. Also, the recirculating charcoal filter is included. The turntable can be turned off when using larger dishes. Model JNM3161DFBB is the same microwave except assembled for indoor (recirculating) venting. Thanks for checking with us!