Hi Wkarraker,
I have the MakerBot Replicator 5th Generation. It is not heated and doesn't have a heated build plate, and it is not enclosed. But I did cover the 3 sides of it with plastic so it is partially enclosed now. The top is still open though. I have data logger also, that is how I know what the temps were. The inside temp of the printer right next to the build plate was about 85F. With the older v12 extruders (when they worked) I covered the whole printer with a bag and got inside temps of about 95F, sometimes over 100F, and they didn't jam usually. Do you have the SmartExtruder+? Is it working good? Thanks.