Came out today to inspect a ac system that the homeowner installed. Upon arrival the homeowner showed me the system in question. This is window unit that is installed in the wall. I explained to the homeowner that this is not in our scope of work but I offered to check her boiler system that has not been serviced in a couple years. This is a Weil McLain boiler system. Model #Cga-4pidn, Cp# 6823962. Upon arrival the thermostat was turned off. I called for heat and observed the system starting normally. I found that the system had no water pressure. I found a fault in the automatic water delivery system. I was able to fill the system manually. I took a combustion analysis test and received the following readings, 02 is at 12.2% and the co levels are at 13ppm. I powered the system back down and allowed the system to cool. I removed and cleaned out the burners and burner box. Cleaned the flame sensor and re inserted the burners. The expansion tank and circulator pump are both in good condi