Customer still not getting heat upstairs just like last visit, customer had changed circulator pump, still pipes not getting hot when I fired boiler up, found a small amount of air in lines, purged second floor zone through two cycles of boiler and tested system, pipes began to get hot, went to second floor and took a delta t reading with a 40 degree temperature split and about 110 degrees coming through vents, second floor now has heat also fixed damper on exhaust for customer as well weight needed to be adjusted.