DO radiation exterior semi-transparent wall
 

Hi,
I'm trying to simulate a simple window using DO-radiation. Both sides of the window are defined as semi-transparent, for the radiation to pass through the window. Absorption and scattering coefficients are used.

My issue is that although all surfaces are adiabatic, the temperature of the window should increase due to the incoming radiation. But, the temperature decreases. This is because the total radiation heat transfer from the side where radiation exits the window, is higher than the incoming radiation.
How should I define the window side opposing the incoming radiation ?

Thanks...