Caught the 6:15 am sailing from Anacortes. Arrived on site. Shut down and isolated boiler. Performed partial removal and disposal of existing combustion air & vent piping. Disconnected fuel piping and low-voltage wiring as required. Removed existing heat exchanger as required. Provide and install new Buderus combustion air / vent kit. Reinstalled existing heat exchanger. Performed new venting and combustion air piping as required. Reconnected gas piping and low-voltage wiring. Replaced pressure switch as required. Returned system to service. Increased pressure at PRV from 12PSI to 15PSI. NOTE: Increase in pressure resolved the flashing “H7” error code. Performed testing of carbon monoxide in boiler cabinet. No traces of CO were discovered. Perform testing for gas leaks. No traces of gas were discovered. Cycle tested indirect hot water heater. Confirmed operation of thermostats. All components of hydronic heating system are performing as designed. Arrived