1 - Locate the boiler system in the basement using the following floor plan
2 - Locate the boiler sight-glass on the side of the boiler system If the sight valve is 50%-60% full, then stop this procedure as the problem is somewhere else in the system If it less than 50% full, then proceed with the next steps.
3 - Find the water valve that feeds water into the boiler system.
4 - While watching the fill valve, open the water valve and fill the system to no more than 66% full.
5 - Shut off the valve