We replaced the boiler that was here because it leaked at the upper nipple joint. In one picture you can see someone found the leak in 1999 and even noted it on the boiler with a marker. They told each subsequent serviceman the boiler leaked. It would have been nice if they had actually told the homeowner. But they didn't, and when I did we got the job of replacing the boiler. The system is a Trane Company system so we installed a low fire gas valve to keep the boiler in vapor. The Trane systems were vapor systems. We lowered the water seal at the end of the main so that we didn't need a false waterline or have to put the boiler up on a pedestal.