Performed preventative maintenance for a Weil-McLain boiler. I observed the system starting normally. I took a combustion analysis test and got the following readings, 02 is at 17%, co is at 12ppm and the system is operating at 78% efficiency. Upon arrival the water pressure was at 5psi. The auto fill was not operating due to the water shut off valve was in the closed position. I filled the system to 15psi. The circulator pump is operating normally and the limit is set for 180F. All 3 zone valves are operating properly and in good condition. The system is operating properly at this time.