I'm a complete newbie when it comes to HVAC. I did manage to install a new thermostat with help from here so I try again. I have a oil burner baseboard hot water system. My hot tap water is also heated through the burner. I know how I can change the temperature for the tap hot water, but can I change the temperature of the water that goes through my baseboard radiators? I attach a picture of what the system looks like since I am not able to describe the it in any meaningful way hoping the picture may tell someone something.
I think I found the aquastat for the heating. It's on the boiler itself. I have attached two new pictures. Is there any benefit to setting the temperature up? I also wonder what that metal piece attached to the temperature wheel is? That piece is set at around 170 it seems.