Gravity boiler (1920 Mueller model number: 1-28-W, serial: 44248) Burner cover was not put in place properly. Found system needed more water. Added water and bled air third-floor radiator. Other third-floor radiator has broken vent Found expansion tank waterlogged. May cause excessive pressure and water release at pressure relief valve. Combustion gases are leaking at front and rear access doors. Boiler in need of cleaning and sealing. Boiler will need tuning with combustion analyzer for proper primary, secondary, and gas pressure adjustments. Thermostat cycles too fast for gravity type system. (Efficiency loss). Has very old white Rodgers digital thermostat with no cycle rate adjustment instructions available. Customer is planning to sell the home. Wants pricing to replace boiler.