Located in the basement of the old bank-Performed preventative maintenance for a Weil McLain boiler model #E-6, serial # not visible. I powered the system down and removed the access panels. I cleaned out the burners and burner box. Cleaned the igniter and flame sensor as best I could without damaging the system. This is a very old boiler and should be updated. The water pressure is at 20psi and all the electrical connections are secure and in good condition. Checked the copper piping for leaks. Once the burners were re attached I powered the system back up and called for heat. This boiler system is connected to split air conditioner system to allow forced air heat. I observed the system starting normally. I took a combustion analysis test and received the following readings, o2 is at 11% and the co levels are 23 ppm. The system is operating properly at this time. Performed preventative maintenance for a Bryant split system that is attached to 2 separate condensers. Indoor Bryant unit