An _________ is a pressure actuated diaphragm valve used to maintain a constant pressure  in the evaporator of the direct expansion mechanical refrigeration system:

Both low side and high side ________ are used to control the flow of liquid refrigerant in the refrigerant system:

A heat pump is a refrigeration device used to transfer heat from one room or space to another

________ is the actual temperature of air as measured by an ordinary thermometer:

Brake horsepower (bhp) on the fan motor will vary ______ of the rpm ratio:

______ is the height of the column of warm air that causes the chimney action of the ventilator:

The top of the chimney should be at least _____ higher than the roof:

The ambient temperature is assumed to be ______ for the purose of sizing radiator heat output estimates:

Radiators adequate air spacing must cover atleast ________ of the total surface of the unit:

The size of the conductor is determined by which of the following:

When two fans are operated in series the cfm is doubled:

An air change every _____ complete changes er hour is desirable for bathroom ventilation:

In a parallel circuit which of the following remains the same:

A _______ must be pitched towards the flow of vapor to ensure that oil returns to the compressor:

Buoyancy ______ as combustion gas temperature increases:

If the carbon dioxide content in the flue gas in boiler goes down, then the efficiency of the boiler _______:

1 ton cooling capacity is equivalent to _____ Btu per hour: