Good morning everyone! I have a new Caldaia Sa26 dual boiler that I installed recently. I already installed all the radiators and purged them. The boiler for sanitary water works without problem, but when I open the radiator circuit charging key it does not rise above 0.8 bar. So far I never turned it on in boiler mode since the pressure is below recommended. What can be? Do I need to put a pressurizing pump before the boiler to increase the water pressure? Thank you!