Does a rotary evaporator need a draft chamber and a vacuum pump? I am using DCM ( dichloromethane) in my research, as a solvent. At the end of the day I have to separate the salute and measure it. 
Up until now, I have been using a constant temperature oven, set a about 65 degree Celsius (evaporation temp of DCM). The exhaust DCM is expelled into the atmosphere and the dried salute is then cooled down and measured. 

I want to replace the oven with a rotary evaporator. However I have an argument with my advisor. He claims that I require two things:


Aspirator /vacuum pump
Draft Chamber


While I agree that a vacuum pump can be of use, I do not require my solvent to boil, therefore I do not need vacuum.

As for the draft chamber, I completely fail to see its implication.
I believe that since the rotary evaporator is a completely closed system, there is no way DCM vapor could leak, rendering the draft chamber useless.
I think you are taking too dogmatic a position overall.

1) Vacuum also increases the rate of evaporation, without boiling.  This is just practical.

2) Your claim that your system is "completely closed" is over confident. What if you are wrong and you have a leak?  Now you are free to dismiss this, but this is the safety issue your adviser is getting at.

In other words, it would be easy to incorporate your practice with industry best practice.