单项选择题
Which action should be taken when an auxiliary boiler in is operation?（）
A.Clean all electrical connections B.Lift the relief valves by hand C.Inspect and clean all solenoid valves D.Inspect for oil and water leaks
单项选择题 Ignition failure in an automatically controlled auxiliary boiler could be caused by（）
单项选择题 Heavy soot accumulations in an auxiliary boiler could be caused by（）
单项选择题 The purpose of the programmed purge cycle on an automatically fired auxiliary boiler is to（）
