Atmospheric pressure is the sum of gauge pressure and vacuum pressure.

The ___ line is a refrigerant line that carries low-pressure refrigerant between an evaporator and a compressor.

A steam system is a boiler system that supplies the proper amount of water to a boiler.

The ___ line is a refrigerant line that carries low-pressure refrigerant between an evaporator and a compressor.

A ___ is a burner accessory that opens when energized by contacts in the programmer to allow fuel oil to flow to a burner nozzle.

A ___ is a burner accessory that opens when energized by contacts in the programmer to allow fuel oil to flow to a burner nozzle.

A boiler must be taken off-line before it can be inspected.

A manhole cover can weigh more than 50 lb, and significant injury and/or damage can occur if it is rapidly pulled in by ___ inside the boiler during removal.

A manhole cover can weigh more than 50 lb, and significant injury and/or damage can occur if it is rapidly pulled in by ___ inside the boiler during removal.

Foaming causes corrosion of heat transfer surfaces.