I have done some newer modifications to the model, instead of having pressure outlet, I have an 'Outflow boundary condition on water leg. This seems to have solved the reversed flow issue, and my average outlet temperature is higher than the entire water average temp (which was wrong in previous model, but now is physically correct).One thing that I did notice is that, the entire outlet is currently having negative pressure as seen below.nnnAnd on top of that, even my inlet has negative pressurennnI want to understand if it is okay to have such pressure, because it seems to be quite low. n