Boundary Conditions for Joule Heating - COMSOL

Hello I am attempting a 2d simulation of micro heater array on a Silicon wafer. I have the actual design in autocad and imported the same in comsol v 5.3. The wafer is a p type Si whereas the heating elements are made of Gold . I just went the simple way by adding joule heating from the library and defining the voltage and heat transfer in solids modules. I want the temperature distribution to be even throught the heating elements and therefore a not defining the boundary conditions of the device being operated at room temperature at the contacts.I defined at the edge of the wafer on either sides. (As seen by the screnshots below) However, I believe the heater wont actually reach 400 degrees C just on application of 0.1V. I also assigned a heat flux at all the edges with a convection coeff of air i.e 20. I am still at the early stages of comsol and have no idea on where else to specify the boundary [login to view URL] that the device is being operated at room temperature. If I remove the temperature node then its an astronomically high temperature as there is no heat leaving the system. Any help on this is appreciated