A feedwater ___ valve is located next to a feedwater stop valve and prevents feedwater from flowing from the boiler back to the feedwater pump.

Stop valves before and after a pressure-reducing valve allow servicing of the pressure-reducing valve.

A steam strainer should be located in a steam line after a steam trap.

Stop valves before and after a pressure-reducing valve allow servicing of the pressure-reducing valve.

A(n) ___ is a hot water boiler fitting that serves as a boiler water setpoint temperature control system with an outside air thermostat.

___ is the condition where a flame travels upwind and into the burner assembly.

Oxygen in boiler water is used to remove nonadhering sludge.

A ___ is a dynamic pump with a rotating impeller inside a cast iron or steel housing.

A ___ is a dynamic pump with a rotating impeller inside a cast iron or steel housing.

Scale acts as an insulating material and reduces the transfer of heat to water.